Bleach catalysts

Abstract

Bleach catalysts comprise at least one metal ion coordinated to at least one ligand based upon a common structural element of (4,5-Dihydro-1,3-oxazol-2-yl)benzene and more preferably upon a o-(4,5-Dih

Description

TECHNICAL FIELD The present invention concerns bleach catalysts and certain applications. 5 BACKGROUND Industry standard bleach catalysts in the dishwashing detergent industry include CAS 640-67-5 (manganese oxalate), CAS 6556-16-7 (manganese oxalate dihydrate), CAS 116633-53-5 (Mn-Mes-tacn), 10 and certain cobalt-based complexes. These and other conventional bleach catalysts suffer from one or more of the following disadvantages: 15 20 1. They are conventionally manufactured from fossil fuels; 2. They are non-biodegradable; 3. They are toxic; 4. They are damaging to some materials, such as textiles; and 5. Their performance is not as good as other industry standards characterised by one or more of the aforesaid disadvantages. 15 09 25 The present invention aims to provide improved bleach catalysts in at least one of these respects. There is some recognition in the prior art that certain oxazoline-derived ligands can be useful in certain types of catalysis. 25 US2023 / 203211 discloses organometallic Ziegler-Natta catalysts derived from oxazoline compounds for the production of higher molecular weight polyethylenes. Living cationic ring-opening polymerization of 2-oxazolines initiated by rare-earth metal triflates are 30 disclosed in RSCAdv., 2014,4, 59917-59926. Additionally, other ring-opened oxazoline derivatives are disclosed in EP1390340. GB2422832A discloses Group 3B, 4B and rare earth metal precursors for chemical vapour deposition comprising a metal and at least one ligand having oxygen and nitrogen available for co-ordination with 35 the metal, the oxygen and nitrogen being separated by 2 or 3 carbon atoms in the ligand and having sterically hindering groups on the nitrogen and / or the oxygen and / or a carbon adjacent to nitrogen and / or oxygen. WO02 / 102707A2 discloses methods for carrying out nucleophilic addition reactions using oxo-, 40 sulfido- or amido-complexes of transition metals as reaction catalysts. Nucleophilic addition reactions that can be catalysed using the present methods include silylation, hydrosilylation, hydroamination, silylmetallation, carbometallation, aldol reactions, hydro- and carbometallation initiated cyclization / polymerization, and epoxide / aziridine opening. The disclosure also pertains to novel transition metal complexes that have utility in catalysing such reactions. 45 15 09 25 US2005 / 0235428A1 discloses the use of metal complex compounds as oxidation catalysts. The present invention relates also to formulations comprising such metal complex compounds, to novel metal complex compounds and to a method of catalysing oxidations, wherein at least one complex compound according to the invention is added to the oxidising agent. 5 Other relevant disclosures include: Stereoisomers and functional groups in oxidorhenium(V) complexes: effects on catalytic activity, Dalton Trans., 2019, 48, 8106-8115. 10 Iron complexes of chiral phenol-oxazoline ligands: Structural studies and oxidation catalysis, Inorganica Chimica Acta, 360 (2007) 1954-1960. Arene-ruthenium complexes with salicyloxazolines: diastereoselective synthesis, configurational 15 stability, and applications as asymmetric catalysts for Diels-Alder reactions, Dalton Trans., 2004,1481-1492. A mild catalytic synthesis of 2-oxazolines via oxetane ring-opening: rapid access to a diverse family of natural products, Chem. Sci., 2019,10, 9586-9590. 20 Titanium and Vanadium Catalysts with 2-Hydroxyphenyloxazoline and Oxazine Ligands for Ethylene-Norbornene (co)Polymerization, Catalysts 2019, 9(12), 1041. Palladium and copper complexes with oxygen-nitrogen mixed donors as efficient catalysts for the Heck 25 reaction, Inorganica Chimica Acta 383 (2012) 46-51. Electrochemical and Catalytic Properties of Novel Manganese(lll) Complexes with Substituted 2-(2'-Hydroxyphenyl)oxazoline Ligands - X-ray Structures of Tris[5-methyl-2-(2'-oxazolinyl)phenolato]manganese(lll) and Tris[5-chloro-2-(2'-oxazolinyl)phenolato]manganese(lll), 30 European J. Inorg. Chem., (2002), 377-387. Synthesis, Structure, and Catalytic Properties of V-IV, Mn-lll, Mo-VI, and U-VI Complexes Containing Bidentate (N, O) Oxazine and Oxazoline Ligands, Inorganic Chemistry, (2004), 43(18), 5704-5713. 35 C 2-Symmetric Group 4 Metal Complexes Adorned with Chiral N,0 Chelates: Synthesis and Structural Characterization of Helical Hexacoordinate Metal Dichlorides Derived from 6-lsopropyl-3-methyl-2-(4-isopropyl-4,5-dihydrooxazol-2-yl)phenol Ligands, Z. Anorg.Allg. Chem., (2009), 635 (9-10), 1435-1441. Synthesis, Structures, and Magnetism of Three ID Mn-lll Chains with Oxazoline-Based Ligands, 40 Inorganic Chemistry, (2010), 49, 5868-5875. A general and convenient route to oxazolyl ligands, Tetrahedron Letters, (2011), 52, 5120-5123. Bleach catalysts are effective to enhance the activity of peroxygen bleaches such as hydrogen peroxide, hydrogen peroxide liberating or generating compounds, and / or inorganic and organic peroxyacids. None of the above disclosures contemplate or disclose such activity. 5 The present invention seeks to provide bleach catalysts with comparable functionality to the best of the above-mentioned industry standards, but with fewer environmental drawbacks. SUMMARY OF INVENTION 10 According to a first aspect of the invention, there is provided a bleach catalyst comprising at least one metal coordinated to at least one ligand of formula (I) having the structure: (I) 15 09 25 15 wherein n is 1 or 2; m is 1 to 4, when the or each R independently represents H; or m is 1 or 2, when the or each R independently represents CH3, C2H5, C3H7, C4Hgor OH, or OR1 wherein R1 represents CHsfCHzJv, wherein v is 0 to 17, which chain may be hydroxy- or alkoxy- 20 terminated, or NR22, wherein: R2 represents H or CH3(CH2)W, wherein w is 0 to 17; or R2 represents alkoxyalkyl; and R' represents H, CH3, CH2CH3, CH(CH3)2, (CH2)yOH or (CH2)yCOOH, wherein y is 0 to 17; R" represents H, CH3, CH2CH3,CH2OH, CH2CH2OH, CH2OCH3or CH2CH2OCH3; 25 R'" represents: H; or C(O)R3, wherein R3 represents (CH2)ZR4, wherein z is from 1 to 18 and R4 is H, OH or COOH; or -R5-R6, wherein R5 represents Ci to C4 alkyl, and R6 represents H, CH3, OH, COOH, 30 OCH3, OCH2CH2OH or OCH2CH2OCH3, or CH(OH)CH2OH. In embodiments according to the first aspect of the invention, the or each R may be H, CHfCHsh, CfCHsJs, CH2CH3, and OH. In most preferred embodiments the or each R is H. 35 In embodiments according to the first aspect of the invention, wherein when the or each R represents NR22 and R2 represents H or CH3(CH2)W, w is preferably 0. 15 09 25 In embodiments according to the first aspect of the invention, wherein when the or each R represents NR22 and R2 represents alkoxyalkyl, the alkoxyalkyl may be preferably selected from hydroxyethyl ((CH2)2OH), or hydroxypropyl. 5 In embodiments according to the first aspect of the invention, R may be preferably located in positions 4, 5 or 6 of the aromatic ring. In embodiments according to the first aspect of the invention, R' is preferably H, and R" is preferably H. 10 In embodiments according to the first aspect of the invention, wherein R'" represents C(O)R3 and R3 represents(CH2)zR4, R4 is preferably OH. In embodiments according to the first aspect of the invention, wherein R'" represents -R5-R6, R5 is 15 preferably methylene. In embodiments according to the first aspect of the invention, the at least one metal may be selected from iron (Fe), manganese (Mn), copper (Cu), or cobalt (Co). 20 In preferred embodiments of the invention, the transition metal ions may be iron(ll), iron(lll), manganese(ll), manganese(lll), copper(ll), cobalt(ll), or cobalt(l 11). In most preferred embodiments of the present invention, the transition metal may be manganese or cobalt, most preferably manganese, still more preferably manganese (II) or (III). 25 The bleach catalyst of the present invention may be preferably a chelate of the transition metal element manganese, preferably wherein Mn is in the Mn3*, Mn(III), oxidation state. In embodiments, the bleach catalyst may be preferably a hexadentate complex. 30 In a preferred embodiment of the invention, the bleach catalyst may comprise two ligands of formula (I) chelated to one transition metal element. In some embodiments, the bleach catalyst may comprise one or more further ligands not being the 35 ligands of the invention. For example, the bleach catalyst may comprise of two further ligands not being the ligands of the invention. The further ligands may be selected from H2O, carbonate, hydroxide, a halide, or an organic acid. In preferred embodiments, the further ligands may be selected from, H2O, Cl, and acetate. 40 The bleach catalyst according to the first aspect may be formulated for use as a bleach catalyst. In preferred embodiments the bleach catalyst may be formulated for use as an oxidative bleach catalyst. In some cases, the formulation may additionally comprise at least one ancillary compound, optionally selected from one or more of surfactant(s), detergent(s), bleach(es), carrier compound(s), stabilizer(s), and / or dispersant(s). 15 09 25 5 According to a second aspect of the invention there is provided use of a bleach catalyst comprising at least one metal coordinated to at least one ligand of formula (I) according to the first aspect of the invention. According to a third aspect of the invention there is provided a method for bleach catalysis comprising 10 contacting a bleach catalyst according to the first aspect of the invention with a bleach under conditions effective to allow the compound to enhance a bleaching process. Certain ligands of formula (I) have not previously been disclosed (as bleach catalysts or otherwise). Consequently, the invention also provides the compounds of formula (I) such as have not previously 15 been disclosed, for any useful application. DETAILED DESCRIPTION The bleach catalysts of the present invention are based upon a common structural element of (4,5-20 dihydro-1,3-oxazol-2-yl)benzene and more preferably upon a o-(4,5-dihydro-l,3-oxazol-2-yl)phenol core, which may also be referred to as a dihydro-oxazol-phenol or DOP structure, shown in formula (II): In particular embodiments formula (II) may be ring substituted with ancillary groups, esterified, or etherified. 30 The compound may be optionally substituted with ancillary groups. Ancillary groups are considered to be groups which do not fundamentally alter the chelating ability of the compound. The inclusion of ancillary groups is helpful in tailoring and altering the hydrophobicity, hydrophilicity, and steric hindrance of the catalytic centre. Adjusting these parameters is able to enhance the overall 35 biodegradability of the ligand. In general, shorter alcohol chains and alkyl chains with a hydrophilic element are preferred so as to enable those characteristics to be achieved without presenting often poorly degradable long alcohol chains. As such, R preferably represents OH or NH2, most preferably OH, to provide a more hydrophilic structure with improved biodegradability. In addition, an ether or amine may preferably be present, providing the more labile ether or amine 5 functionality between an alkyl (chain) and the benzene ring in which case: R1 represents CHafCHzJv, wherein v is 0 to 17; or v is preferably 6 to 12 thus providing hydrophobicity without the potential for evolution of volatile short alkyl components, such as during high alkaline washing operation in which catalyst may be used; R2 represents CH3(CH3)W, wherein w is 0 to 17; or R1 or R2 represents (CH2)2-OH. The terminal hydroxy group improves biodegradability and ensures high water solubility. 15 When an ancillary group is present on the benzene (phenolic) ring it is preferably present in positions 4, 5 or 6, more preferably 4 or 5. To illustrate: 15 09 25 (ID This is understood to provide better bleaching by the bleach catalyst, particularly on hydrophobic surfaces as the catalytic centre is less hindered whilst the overall complex is more hydrophobic. 25 In this light, when R is in positions 4, 5 or 6, R can represent (CH2)xCH3, wherein x is 0 to 17, x is preferably 6 to 12 thus providing hydrophobicity without the potential for evolution of volatile short alkyl components, such as during high alkaline washing operation in which catalyst may be used. The compound may be esterified or etherified. In some cases, R'" is preferably an ester, which improves the biodegradability of the compound. In other embodiments R'" is preferably an ether, rendering the compound more stable in an alkaline environment, such as during the washing process. The ester or ether may be distanced from the benzene ring by means of a spacer chain R5, R6, respectively. This spacer chain may enable a wider range of metal ions to be chelated, such as Co in addition to Mn, ions. 15 09 25 R'" may comprise an alkyl chain, this may provide a degree of hydrophobicity to the ligand and thereby to a chelate created using the ligand. This can be advantageous in enabling catalytic bleaching of hydrophobic substrates. 5 The ligand compounds are chelated with metal ions to form catalysts, such as may be suitable for catalysing oxidative bleaching. The compounds are biodegradable and thus prevent catalyst build up in the environment. The 4,5-dihydro-l,3-oxazol-2-yl ring may also be substituted. 10 R' preferably represents H, CH3, CH2CH3, CHfCHsh, (CH2)yOH or (CH2)yCOOH, wherein x is 0 to 17, and y is preferably 6 to 12. R" preferably represents H, CH3, CH2CH3, CH2OH, CH2CH2OH, CH2OCH3 or CH2CH2OCH3: most preferably 15 one or both of R', R" are H. This is particularly desirable when one or more of the other ancillary substituents represents an alkyl chain. Combinations of substituents: 20 Preferred combinations of substituents are as follows: m is 1; in R is 0 to 5, w is 0 to 5 and x is 0 to 5; R" represents H or CH3, as these ligands are readily synthesised, biodegradable, and effective as catalysts in chelate form with manganese to provide catalysis of oxidative bleaching. A preferred subset is provided by the selection: 25 R represents H, CH3, OH, OCH3, or N(CH3)2; R' represents H, CH3, CH2OH or (C^hCOOH; and R'" represents H or - R5-R6, wherein R5 represents C1-4 alkyl and R6 represents COOH. An example structure being Formula (III): A preferred subset is provided by the selection: 35 R represents H, CH3, OH, OCH3, or NfCHsh; R' represents H, CH3, CH2OH or (C^hCOOH; R'" is an ester, representing C(O)R4, where R4 represents (CH2)ZR5 with z being 1, 2 or 4, and R5 represents H, OH or COOH. An example structure being Formula (IV): 15 09 25 (IV) Therefore, there are provided, structures which are particularly biodegradable. For the same reasons, a further preferred combination is wherein m is 1; R wherein v is 6 to 17, w is 6 to 17 and x is 6 to 17; and R" represents H. These more hydrophobic ligands provide greater recovery in sewage sludge and are thus less readily to be found as catalysts in chelate form with manganese to provide catalysis of oxidative bleaching, particularly of hydrophobic substrates, such as hydrophobic stains. 15 In the present invention n is preferably 1. In the present invention n may be 2, as such potentially providing a more hydrophobic ligand, particularly when in conjunction with the previously mentioned hydrophobic variations of R. 20 In the present invention m is preferably 1 and in R any v is 0 to 5, any w is 0 to 5 and any x is 0 to 5; R' and R" independently represent H or CH3; R'" represents H. R wherein at least one of v, w and z is 6 to 17; preferably at least two of v, w and z is 6 to 17; most preferably any v is 6 to 17, any w is 6 to 17 and any x is 6 to 17. 25 The present invention preferably comprises: R wherein at least one of v, w and z is 6 to 17; preferably at least two of v, w and z is 6 to 17; most preferably any v is 6 to 17, any w is 6 to 17 and any x is 6 to 17; R' and R" independently represent H or CH3; preferably H; and R'" represents H. 30 The present invention preferably comprises: R represents H, CH3, OH, OCH3, or NfCHsh; R' represents H, CH3, CH2OH or (CHzhCOOH; R" represents H; and R'" provides an ether. In certain embodiments of the present invention n is preferably 1. 35 In other embodiments n is preferably 2. In some embodiments m is preferably 1. As can be seen the structure comprises the common structural element, of Formula (II): Formula (II) may be referred to as o-(4,5-dihydro-l,3-oxazol-2-yl)phenol or more formally as 2-(4,5-dihydro-l,3-oxazol-2-yl)phenol. For simplicity of communication the structural unit is referred to by 10 the label DOP, dihydro-oxazol-phenol in this document. 15 09 25 In the present invention a number of groups of specific compounds are preferred, these groupings represent families of readily synthesised compounds having good, calculated, good biodegradability characteristics and an ability to chelate transition metal ions, particularly manganese ions. 15 These are: a) The present invention wherein n = 1; m = 1; R' is H or CH3; R" is H or CH3; R'" is H and the compound has a structure selected from those set out in the table below. 20 b) The present invention wherein n = 1; m = 1; R is N(CH2)2-OH); R' is CH3; R" is CH3; R'" is H and the compound has a structure selected from those set out in the table below. c) The present invention wherein n = 1; m = 1; R' is H or CH(CH3)2; R" is H; R'" is H 25 and the compound has a structure selected from those set out in the table below, d) The present invention wherein n = 1; m = 1; R' is CH2OH; R" is H; R'" is H 30 and the compound has a structure selected from those set out in the table below, e) The present invention wherein n = 1; m = 1; R' is (CH2)2COOH; R" is H; R'" is H and the compound has a structure selected from those set out in the table below, f) The present invention wherein n = 2; m = 1; R' is H; R" is H; R'" is H and the compound has a structure selected from those set out in the table below. 35 If any of the compounds set out in the table below does not conform to the abbreviated list of requirements for the substituent, then the compound still remains part of the invention. The requirements in each claim are presented for clarity of presentation. In accordance with the invention, preferred examples of the bleach catalyst ligands are provided in the table below: Table 1: Summary of Structures Codes Structure and Description 1000- 1041 _(T H In embodiments of general formula la, the compounds may particularly have one of the following particular structures: 15 09 25 LO CXI 1100- 1532 In further embodiments according to the present invention, the compounds may have a structure combining one of the oxazolyl ring systems with one of the substituted aromatic ring systems. 15 09 25 Preparation of Bleach Catalyst Ligands The compounds of the present invention may be prepared by known synthetic techniques. Given the wide range of compounds (ligands) within the scope of the present invention, a general scheme, more specific scheme, and a particular synthesis are provided, from which the skilled person would be able to reasonably adapt the procedure for any given specific compound preparation. 10 The preferred synthetic route or compounds of the present invention uses the scheme: OR NH RB RB O ra^O^ OR Amidine reagent and / or catalyst O RB reagent and / or catalyst Oxazoline O RA^OH Amide 15 09 25 The reaction of a carboxylic acid or its derivatives, such as its methyl ester or its nitrile, with an alpha substituted beta hydroxy amine can take place in two separate stages or a single stage, "one pot", 5 reaction, i.e. telescoping both stages and producing the basic oxazoline unit of the present invention. The required raw materials are readily available from sustainable sources, such as biological or bioderived feedstocks. The above reaction scheme is related to the Pinner reaction for the condensation of a carboxylic acid 10 with an a-substituted p-hydroxy amine to form an oxazoline. Reagents and catalysts include but are not restricted to thionyl chloride (SOCL), oxalyl chloride (C2O2CI2), p-toluene sulfonic acid, methane sulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, or hydrogen chloride. 15 An outline reaction scheme is provided as follows, and the skilled person would be able to readily adapt these as required. The following reagents are provided: 20 An aromatic carboxylic acid relevant to the structure intended (see table below). An a-substituted p-hydroxy amine relevant to the structure intended (see table below). Thionyl chloride (SOCI2) can be used as a reagent in both stages, first to form, in-situ, the acyl chloride from the carboxylic acid which subsequently reacts with the amine, making the compound more reactive toward cyclisation. 25 A suitable solvent for the reaction is usually anhydrous (water-free) and polar. Suitable solvents include dichloromethane (CH2CI2) or chloroform (CHCI3). These solvents help dissolve the reagents and promote the reaction. Alternative solvents available from renewable feedstocks include, for example tetrahydrofuran (THF, C4H8O), which has a lower toxicity compared to dichloromethane and chloroform and is derivable from renewable resources through the hydrogenation of furfural, which 30 may be obtained from lignocellulosic biomass. Another example would be methyl tert-butyl ether (MTBE, C5H12O), which also has lower toxicity and is derivable from renewable feedstocks such as isobutene, which can be produced from biomass-based sources. An additional example would be 2- 15 09 25 Methyltetrahydrofuran (2-MeTHF, C5H10O), which has similar properties to THF and can be produced from renewable feedstocks, such as biomass-derived sugars or furfural. The reaction is typically carried out at a moderately low temperature, for example around 0-10°C. 5 Carrying out the reaction in this range helps control the reaction rate and minimize undesired side reactions, and the generation of undesirable side products. An outline reaction procedure is as follows: 10 In a dry and inert atmosphere (e.g., under nitrogen), the carboxylic acid and a-substituted p-hydroxy amine are combined in the chosen solvent. A catalytic amount of base, such as triethylamine (EtaN), is added to neutralize the hydrogen chloride formed during the reaction. 15 Thionyl chloride (SOCI2) is gradually added to the reaction mixture, typically dropwise, whilst maintaining a constant reaction temperature. The reaction mixture is stirred for a specific period, usually several hours, to ensure completion of the 20 reaction. The reaction is quenched by addition of a suitable quenching agent, such as ice or water, to destroy any excess thionyl chloride and neutralize the remaining acidic components. 25 The product is extracted from the reaction mixture using a suitable solvent, or further purification steps are carried out, such as for example column chromatography or recrystallization. A skilled person in the art will be able to adapt the specific reaction conditions using their common general knowledge. 30 Example combinations of reagents to produce compounds of the present invention is provided in the following table, Table 2. 15 09 25 A more specific example procedure, such as, for compound of Formula (II) is provided as follows: A mixture of methyl ester functionalized phenol (1 eq.) and hydroxyalkylamine (1.05 eq.) is heated to 5 130°C and the methanol of reaction is distilled until no further distillation is observed and the reaction is complete. The resulting residue is cooled to room temperature and suspended in a solvent selected from dichloromethane, methyl tert-butyl ether or methyltetrahydrofuran (4 vol). After cooling to 5°C, thionyl chloride (1.1 eq.) is then added dropwise to the mixture. After complete addition, the reaction is stirred for 16h at 25°C. The resulting solids are then filtered and neutralized with 10% NaHCOs 10 solution before being extracted with methyl tert-butyl ether (3X1 vol). Organic extract is then concentrated to dryness under vacuum to give the target ligand structure. A specific synthesis of compound of Formula (II), is provided as follows: 15 A mixture of methyl salicylate (273.9g, 1.8mol) and ethanolamine (115.8g, 1.9mol) is heated to 130°C and the methanol of reaction is distilled until no further distillation is observed and the reaction is complete. The resulting residue is then cooled to room temperature and suspended in dichloromethane (IL, 4 vol). After cooling to 5°C, thionyl chloride (237.5g, 2.0mol) is then added dropwise to the mixture. After complete addition, the reaction is stirred for 16h at 25°C. Resulting 20 solids are then filtered and neutralized with 10% NaHCOs solution before being extracted with methyl tert-butyl ether (3 X 150mL). Organic extract is then concentrated to dryness under vacuum to give to give product as a red oil which crystallizes to peach / pink solid on standing. Solids ground to give a peach / pink powder in 68% yield (292.5g, 1.22mol). 25 Analytical Data: GCpurity: 99.5%; FT-IR: nC=N 1636cm1; 2H NMR (Methanol-cU, 300 = MHz, d): 7.56 (dd, 1H), 7.29 (ddd, 1H), 6.89 (dd, 1H), 6.79 (ddd, 1H), 4.28 (t, 2H), 3.93ppm (t, 2H); ^C^H} NMR (methanol-d4, 75MHz, d): 165.87, 159.45, 132.90, 127.75, 118.32, 116.01, 110.57, 66.61, 52.91ppm; Elemental analysis: C 65.66%, H 5.45%, N 8.62% 30 Chelate The bleach catalyst chelate provided by coordination of the at least one metal coordinated to at least one ligand of Formula (I) is preferably a hexadentate complex. 15 09 25 The bleach catalyst chelate is preferably comprising two ligands chelated to 1 transition metal element. The bleach catalyst chelate preferably comprises one or more further ligands not being the ligands of the invention. The bleach catalyst chelate preferably consists of two further ligands not being the 5 ligands of the invention. The further ligands are preferably selected from H2O, carbonate, hydroxide, a halide, or an organic acid. The further ligands are preferably selected from, H2O, Cl, and acetate. The bleach catalyst chelate of the present invention is preferably a chelate of a transition metal. Preferred transition metals may be selected from iron (Fe), manganese (Mn), copper (Cu), or cobalt 10 (Co). In preferred embodiments of the invention, the transition metal ions are iron(ll), iron(lll), manganese(ll), manganese(lll), copper(ll), cobalt(ll), or cobalt(III). 15 In most preferred embodiments of the present invention, the transition metal is manganese or cobalt, most preferably manganese, still more preferably manganese (II) or (III). The bleach catalyst chelate of the present invention is preferably a chelate of the transition metal element manganese, preferably wherein Mn is in the Mn3*, Mn(III), oxidation state. 20 The mode of action of the prepared bleach catalyst chelate of Mn(lll) is that it reversibly cycles between the Mn(lll) and Mn(IV) oxidation states during the bleaching process, which has been confirmed to be chemically reversible by cyclic voltammetry (+0.5V), as shown in Figure 1, a cyclic voltammogram for the action of the bleach catalyst according to the present invention. A proposed 25 mechanism is provided in Figure 5. Preparation of the bleach catalyst Given the wide range of bleach catalysts within the scope of the present invention a general scheme, 30 more specific scheme and a particular synthesis are provided, from which a person skilled in the art would be able to reasonably adapt for any given specific bleach catalyst preparation. An outline scheme for preparation of the bleach catalyst of the present invention is provided as follows: 35 The ligand, for example Formula (II) (o-(4,5-Dihydro-l,3-oxazol-2-yl)phenol), and the metal salt, for example manganese(ll) chloride tetrahydrate (MnCL-AFbO) are provided. A solution of the ligand is prepared by dissolving a suitable amount of the ligand, o-(4,5-Dihydro-l,3-40 oxazol-2-yl) phenol, in a solvent such as ethanol or dimethylformamide, to form a clear solution. The solution may have a concentration in the range 0.1 to 0.5mol / l. In a separate container, the manganese(ll) chloride tetrahydrate (MnCl2-4H2O) is dissolved in ethanol, to form a manganese salt solution. The concentration of the manganese salt can be adjusted to provide 45 a twofold excess of the ligand. 15 09 25 The ligand solution is slowly added to the manganese salt solution whilst stirring. The addition of the ligand solution should be done dropwise and with continuous stirring to ensure effective mixing. The process may be carried out in the temperature range 40 to 80 °C. 5 After the addition is complete, the reaction mixture is stirred for several hours, for example 3 hours, to allow the ligand to coordinate with the manganese ions and form the desired manganese-based catalyst complex. The reaction progress may be monitored by UV visible spectroscopy. 10 A solution of acetic acid is prepared in a suitable solvent, such as for example ethanol. The concentration of the acetic acid solution may be adjusted based on the desired catalyst composition. The acetic acid solution is slowly added to the reaction mixture whilst maintaining stirring, such as over a period of one hour. The addition of the acetic acid should be done dropwise or with continuous 15 stirring. Upon completion of the reaction, the manganese-based catalyst can be isolated by common techniques such as filtration, precipitation, or solvent evaporation. Finally, the isolated catalyst can be washed, dried, and stored in a sealed container for future use in oxidative bleaching reactions. 20 A specific representative procedure for the synthesis of a bleach catalyst according to the present invention, such as for the bleach catalyst of a compound of Formula (II) used in the bleach catalysis methods below, is provided as follows: 25 Oxazoline ligand of Formula (II) (180mmol, 2 eq.) was dissolved in MeOH (900ml, 30 vol). Solid manganese acetate tetrahydrate (21.9g, 90 mmol, 1 eq.) was charged to the ligand solution to give an instant colour change to dark green / black. After 0.25h stirring the mixture was concentrated in vacuo to give an initial residue. Material was resuspended in 900ml and concentrated to dryness twice more to give the final catalyst complex. 30 A specific synthesis of Formula (II) Mn-Complex, is provided as follows: Oxazoline ligand of Formula (II) (30g, 180mmol, 2 eq.) was dissolved in MeOH (900ml, 30 vol). Solid manganese acetate tetrahydrate (21.9g, 90 mmol, 1 eq.) was charged to the ligand solution to give an 35 instant colour change to dark green / black. After 0.25h stirring the mixture was concentrated in vacuo to give an initial residue. Material was resuspended in 900ml and concentrated to dryness twice more to give the final catalyst complex. The sample was ground in a pestle and mortar to give the catalyst product as a green-brown free-flowing powder (41.3g). 40 Analytical Data: FT-IR: nC=N 1621cm1; UV-Vis: lmax = 264nm, 216nm; ICP: 13% Mn content; Elemental analysis: C 53.40%, H 4.59%, N 5.77% The resultant Structural X-Ray Diffraction requirements are shown in Figure 2, and Tables 3-10 show the relevant data collected for the crystal structures. 15 09 25 Table 3: Crystal data and structure refinement for Formula (II) Mn-complex Identification code Formula (II) complex Empirical formula C22H23MnN20g Formula weight 498.36 Temperature / K 120.00 Crystal system Triclinic Space group P-1 a / A 6.3884(2) b / A 9.4519(3) c / A 9.5141(3) a / ° 80.7500(10) P / ° 71.9660(10) v / ° 71.0250(10) Volume / A3 515.42(3) Z 1 Pcalcg / Cm3 1.606 p / mm1 0.696 F(000) 258.0 Crystal size / mm3 0.21x0.11x0.025 Radiation Mo Ka (X = 0.71073) 20 range for data collection / 0 6.634 to 63.994 Index ranges -9 <h <9, -14 <k <14, -14 <1 <14 Reflections collected 20885 Independent reflections 3567 [Rint = 0.0297, Rsigma = 0.0202] Data / restraints / parameters 3567 / 0 / 196 Goodness-of-fit on F2 1.147 Final R indexes [l>=2o (1)] Ri = 0.0288, wR2 = 0.0740 Final R indexes [all data] Ri = 0.0303, wR2 = 0.0747 Largest diff, peak / hole / e A-3 0.42 / -0.28 Table 4: Fractional atomic coordinates (xlO4) and equivalent isotropic displacement parameters (A2x103) for Formula (II) Mn-complex. Ueq is defined as 1 / 3 of the trace of the orthogonalised Uu 5 tensor Atom X y z U(eq) Mnl 5000 0 5000 11.33(6) 01 3351.5(15) 86.0(9) 3657.1(9) 15.44(15) 02 6453.7(15) 3569.2(9) 2133.1(10) 17.11(16) 03 1935.7(15) 1609.3(9) 6456.8(10) 18.09(17) 04 1294.2(16) 3730.8(10) 5057.3(10) 21.68(19) N1 6171.8(16) 1663.2(10) 3833.1(10) 12.28(16) Cl 7428(2) 2444.9(13) 4339.4(13) 16.5(2) C2 7728(2) 3690.5(14) 3120.8(14) 18.3(2) C3 5673.4(18) 2372.2(12) 2646.5(12) 12.33(18) C4 4365.4(19) 2016.4(12) 1828.2(12) 12.74(18) C5 3303.0(19) 867.9(12) 2378.6(12) 13.06(18) C6 2054(2) 561.2(13) 1532.7(13) 17.0(2) C7 1914(2) 1343.6(15) 192.5(14) 20.5(2) C8 2949(2) 2494.8(15) -338.7(13) 20.7(2) C9 4139(2) 2829.8(13) 480.8(13) 16.8(2) CIO 767.6(19) 2914.4(12) 6254.1(12) 14.35(19) Cll -1368(2) 3587.6(15) 7449.5(14) 20.6(2) 15 09 25 Table 5: Anisotropic displacement parameters (A2xl03) for Formula (II) Mn-complex. The Anisotropic displacement factor exponent takes the form: -2n2[h2a*2Un+2hka*b*Ui2+... Atom Un u22 U33 U23 U13 Ui2 Mnl 12.13(11) 11.27(10) 12.29(11) 1.92(7) -5.81(8) -4.64(8) 01 18.1(4) 16.4(4) 15.7(4) 4-1(3) -9-5(3) -8.1(3) 02 19.2(4) 15.5(4) 20.2(4) 4.3(3) -8.5(3) -9-5(3) 03 17.9(4) 13.9(4) 17.9(4) -0.7(3) -3.2(3) -0.5(3) 04 21.5(4) 14.7(4) 19.2(4) 2.0(3) 0.0(3) 0.5(3) Nl 11.6(4) 11.9(4) 14.2(4) -0.8(3) -4.6(3) -3.6(3) Cl 18.6(5) 16.3(5) 19.0(5) 0.4(4) -8.6(4) -8.5(4) C2 19.9(5) 16.0(5) 23.5(5) 1.0(4) -9.5(4) -8.9(4) C3 10.6(4) 10.8(4) 14.1(4) -1.0(3) -2.1(3) -2.3(3) C4 12.5(4) 13.0(4) 12.3(4) -0.9(3) -3.5(3) -3.1(3) C5 13.2(4) 12.3(4) 13.5(4) -0.1(3) -5.1(4) -2.5(3) C6 20.2(5) 16.4(5) 17.9(5) 0.1(4) -9.4(4) -6.7(4) C7 25.2(6) 22.4(6) 18.3(5) 0-2(4) -11.7(5) -8.3(5) C8 26.0(6) 24.4(6) 14.2(5) 3-2(4) -9.1(4) -9-3(5) C9 19.0(5) 17.8(5) 13.5(5) 1-7(4) -4.7(4) -6.3(4) CIO 13.7(4) 13.5(4) 16.3(5) -2.6(4) -4.8(4) -3.1(4) Cll 17-7(5) 18.4(5) 19.1(5) -1.8(4) -0.5(4) -0.8(4) 5 Table 6: Bond lengths for Formula (II) Mn-complex Atom Atom Length / A Atom Atom Length / A Mnl Ol1 1.8687(8) Nl Cl 1.4699(14) Mnl 01 1.8687(8) Nl C3 1.2906(14) Mnl 03 2.2646(8) Cl C2 1.5289(17) Mnl O31 2.2646(8) C3 C4 1.4447(15) Mnl Nl1 1.9884(9) C4 C5 1.4105(15) Mnl Nl 1.9884(9) C4 C9 1.4075(15) 01 C5 1.3215(13) C5 C6 1.4113(15) 02 C2 1.4587(14) C6 C7 1.3802(16) 02 C3 1.3437(13) C7 C8 1.4004(18) 03 CIO 1.2368(13) C8 C9 1.3741(17) 04 CIO 1.2862(14) CIO Cll 1.5057(17) Table 7: Bond angles for Formula (II) Mn-complex Atom Atom Atom Angle / " Atom Atom Atom Angle / " Ol1 Mnl Ol 180.0 C3 Nl Cl 108.94(9) Ol1 Mnl O31 91.76(4) Nl Cl C2 103.19(9) Ol1 Mnl 03 88.24(4) 02 C2 Cl 104.53(9) 01 Mnl 03 91.76(4) 02 C3 C4 117.21(9) 01 Mnl 031 88.24(4) Nl C3 02 115.94(10) Ol1 Mnl Nl1 90.50(4) Nl C3 C4 126.85(10) 01 Mnl Nl 90.50(4) C5 C4 C3 120.34(10) 01 Mnl Nl1 89.50(4) C9 C4 C3 119.68(10) Ol1 Mnl Nl 89.50(4) C9 C4 C5 119.98(10) 031 Mnl 03 180.0 01 C5 C4 124.11(10) Nl Mnl 031 87.83(3) 01 C5 C6 117.80(10) Nl1 Mnl 03 87.83(3) C4 C5 C6 118.06(10) Nl1 Mnl 031 92.17(3) C7 C6 C5 120.90(11) Nl Mnl 03 92.17(3) C6 C7 C8 120.72(11) Nl1 Mnl Nl 180.00(3) C9 C8 C7 119.29(11) C5 01 Mnl 131.43(7) C8 C9 C4 121.01(11) C3 02 C2 107.16(9) 03 CIO 04 122.79(11) CIO 03 Mnl 133.84(8) 03 CIO Cll 119.13(11) Cl Nl Mnl 124.20(7) 04 CIO Cll 118.08(10) C3 Nl Mnl 126.09(8) 15 09 25 Table 8: Hydrogen bonds for Formula (II) Mn-complex D H A d(D-H) / A d(H-A) / A d(D-A) / A D-H-A / ° 04 H4 O41 1.2196(9) 1.2196(9) 2.4393(17) 180.000(0) Table 9: Selected torsion angles for Formula (II) Mn-complex A B C D Angle / " A B C D Angle / " 02 C3 Nl Mnl 172.74(7) C5 Ol Mnl Nl1 -173.60(10) Cl Nl C3 02 2.44(13) C5 Ol Mnl Nl 6.40(10) C3 C4 C5 Ol 2.14(17) C5 C4 C3 02 -173.81(10) C3 C4 C5 C6 -179.74(10) C5 C4 C3 Nl 5.85(17) C4 C3 Nl Mnl -6.92(16) C6 C5 Ol Mnl 173.10(8) C4 C3 Nl Cl -177.22(10) C6 C5 C4 C9 0.76(16) C4 C5 01 Mnl -8.77(17) C9 C4 C3 02 5.69(15) C5 Ol Mnl 03 98.59(10) C9 C4 C3 Nl -174.64(11) C5 Ol Mnl O31 -81.41(10) C9 C4 C5 01 -177.37(10) Table 10: Hydrogen atom coordinates (AxlO4) and isotropic displacement parameters (A2xl03) for Formula (II) Mn-complex Atom X y z U(eq.) H1A 8850(30) 1780(19) 4441(19) 22(4) H1B 6490(30) 2840(20) 5300(20) 25(4) H2A 9270(30) 3540(20) 2540(20) 22(4) H2B 7030(30) 4640(20) 3470(20) 23(4) H4 0 5000 5000 47(9) H6 1330(30) -200(19) 1913(19) 21(4) H7 1040(30) 1100(20) -340(20) 25(4) H8 2800(30) 3050(20) -1280(20) 33(5) H9 4860(30) 3610(20) 140(20) 26(4) H11A -2340(50) 4450(30) 7160(30) 65(8) HUB -990(50) 3610(30) 8300(30) 76(9) H11C -2230(50) 2930(30) 7740(30) 74(9) 15 09 25 Uses Oxidative beach catalysts of the present invention may be used for the bleaching of paper, textiles, 5 stains, hair, and teeth or in wastewater treatment. A preferred use of the oxidative bleach catalyst is in laundry detergents or automatic dishwashing for the discolouration, oxidation and solubilisation of stains and other soiling. 10 Consequently, the invention further provides a detergent composition comprising the aforesaid oxidative bleach catalyst, or bleach activator. The detergent composition may comprise one or more additional detersive surfactants, for example in an amount of from about 1 wt.% to about 15 wt.% detersive surfactant. 15 The bleach activator may be present in the detergent composition for example in an amount of from 0.001 to 5 wt.%, preferably 0.01 to 2 wt.%. In addition to providing an alternative bleach catalyst, the present invention also provides specific 20 advantages, particularly relevant to dishwashing detergent compositions. Specifically, bleach catalysts according to the present invention with the detersive surfactants are, in general, more hydrophobic and, in general, less water-soluble than the most prominent commonly used oxidative bleaching catalyst, MnMea-TACN, Bis(N,N',N"-trimethyl-l,4,7-triazacyclononane)-trioxo-dimanganese(IV) di(hexafluorophosphate) monohydrate (otherwise known as Dragon). 25 The increased hydrophobicity and reduced water solubility of the bleach catalysts gives rise to two advantages in particular detergent compositions, namely that the catalyst in the form of the chelates can dissolve progressively during a cleaning operation, such as dishwashing, and therefore provides constant level of catalyst rather than a high level at the beginning of a wash, which is particularly the 30 coldest, with decreasing activity during the wash. This is facilitated by the presence of surfactant to enable the surface of the bleach catalyst, in a solid state, to be wetted and thereby facilitate improved dissolution kinetics. A further advantage is that the increased hydrophobicity of the bleach catalysts provides additional 35 adsorption onto hydrophobic surfaces, such as greasy surfaces, enabling better cleaning of such surfaces. Surfactant 40 In the present invention the detersive surfactant comprises 1 to 25 wt.%. of detersive surfactant, more preferably from 2 to 15 wt.%. of a detersive surfactant, still more preferably from 3 to 10 wt.%. of 15 09 25 detersive surfactant. These levels enable effective transport of the bleach catalyst to substrate surfaces, such as hydrophobic surfaces to enable improved oxidative bleaching. The detersive surfactant may be anionic, non-ionic, zwitterionic or cationic, more preferably anionic, 5 non-ionic or zwitterionic, still more preferably anionic, non-ionic. Most preferably zwitterionic. The choice of surfactant determines the adsorption of the bleach catalyst onto substrates during detergency and hence bleaching efficiency on a surface, as compared to in solution which is generally ineffective in detergency operations to clean surfaces. 10 Preferably, the detersive surfactant is a mixture of detersive surfactants. In particular, a mixture of an anionic or non-ionic surfactant may be desirable. Non-ionic Surfactants 15 Low-foaming non-ionic surfactants from the group of alkoxylate alcohols may be employed. These surfactants are ethoxylated primary alcohols, specifically those with 8 to 18 carbon atoms and an average of 1 to 12 moles of ethylene oxide (EO) per mole of alcohol. The alcohol residue in these 20 surfactants can be linear or methyl-branched at position 2, or it may consist of a mixture of linear and methyl-branched residues, which is common in oxo alcohol residues. Alternatively, non-ionic surfactants prepared from alcohols of natural origin, such as coconut, palm, tallow fat, or oleyl alcohol, with 12 to 18 carbon atoms and an average of 2 to 8 moles of EO per mole of alcohol are preferred. The preferred ethoxylated alcohols include C12-14 alcohols with 3 to 4 EO, C9-12 alcohols with 7 EO, C13-25 is alcohols with 3, 5, 7, or 8 EO, C12-18 alcohols with 3, 5, or 7 EO, and mixtures thereof, such as a combination of C12-14 alcohol with 3 EO and C12-19 alcohol with 5 EO. Tallow fatty alcohols with more than 12 EO are particularly preferred, with a range of 60 to 100 EO, and even more preferably 70 to 90 EO. Among the non-ionic surfactants, those from the group of alkoxylated alcohols, especially mixed alkoxylated alcohols and EO-PO-EO non-ionic surfactants, are highly favoured due to their foam control 30 properties. EO being ethylene oxide and PO being propylene oxide. Bacterial surfactants, such as Chlorolipids and Rhamnolipids, are glycolipids with non-toxicity, high biodegradability and low surface tension that can be produced by bioconversion of renewable feedstocks. In machine dishwashing detergent compositions, the composition should preferably contain 0.1 to 22 35 wt.% of a non-ionic surfactant or a combination of two or more non-ionic surfactants. The preferred total amount of non-ionic surfactant is between 1 and 17 wt.%, more preferably between 4 and 15 wt.%, and most preferably between 6 and 12 wt.%. These levels are considered optimal. The non-ionic surfactant should be present in amounts ranging from 25 to 90 wt.% of the surfactant system. 40 The non-ionic detersive surfactant for use in the present invention may be one or more of a rhamnolipid or sophorolipid. Commercial examples of such surfactants include BioLoop 56L, BioLoop 56L-PG, BioLoop 68L, BioLoop 68L-PG, BioLoop 84L and BioLoop 84L-PG. Anionic surfactants 15 09 25 In case of a machine dishwashing detergent composition, the amount of anionic surfactant (when present) is preferably at most 4 wt.%, and more preferably at most 2 wt.% and even more preferably at most 1 wt.%. 5 Examples of suitable anionic surfactants include ammonium and sodium lauryl and lauryl ether sulphates, methylester sulphonates, ammonium and imidazolium salts, and phospholipids. Water softeners and builders 10 Builder / water softener materials suitable for use in detergent compositions of the present invention include calcium sequestrant materials, precipitating materials, calcium ion-exchange materials and mixtures thereof. Suitable calcium ion-exchange builder materials include the various types of water-insoluble crystalline 15 or amorphous aluminosilicates, such as zeolites. In particular, Zeolite Y, Zeolite X, Zeolite C, Zeolite B (also known as zeolite P) and Zeolite A may be included. The builder may be crystalline aluminosilicate, preferably an alkali metal aluminosilicate, more preferably a sodium aluminosilicate. The buildup materials preferably have a calcium ion exchange 20 capacity of at least 50 mg CaO / g. The ratio of surfactants to any aluminosilicate in the present invention is preferably greater than 5:2, more preferably greater than 7:2. Also present maybe an alkali metal carbonate this is preferably present in the composition. The preferred amount of alkali carbonate in the composition is from 3 to 74 wt.%, more preferably from 25 10 to 50 wt.% and even more preferably from 20 to 40 wt.%. This level of alkali carbonate provides good Ca2+ and Mg2+ ion sequestration for most types of water hardness levels, and so as to reduce the likelihood of an exchange with the transition metal iron of the bleach catalyst providing good buffering capacity. The preferred alkali carbonates are sodium- and / or potassium carbonate of which sodium carbonate is particularly preferred. The alkali carbonate present in the composition of the invention 30 can be present as such or as part of a more complex ingredient (e.g., sodium carbonate in sodium percarbonate). It has been found that such bleach catalysts provide better absorption onto services being cleaned by the detersive composition. Not wishing to be bound by theory is understood that some degree of 35 positive charge on the bleach catalyst occasion by the amine can interact with negatively charged services, is conventionally understood to be the case, and articles being washed. In the present invention the detersive surfactant preferably comprises a cationic or zwitterionic surfactant. 40 It has been found that these can provide improved bleach catalyst deposition when used in relevant detergent compositions of the present invention. It is hypothesised that the bleach catalysts co-adsorb is with cationic surfactants onto surfaces being washed. In compositions utilising a positively charged surfactant, such as a cationic or zwitterionic surfactant the bleach catalyst of the present invention comprises a ligand with an auxiliary substitution comprising an alcohol chain. 15 09 25 5 It has been found that these provide improved bleach catalyst deposition, possibly because of combination between the negatively charged bleach catalyst and the positively charged surfactant providing improved service absorption. This is particularly beneficial for detersive composition such as fabric softeners. 10 In the present invention the in-use pH of the detergent composition is preferably in the range from pH 8 to 10. This is down particularly beneficial to give absorption of ionisable bleach catalysts of the present invention. Detergents compositions representative of the present invention 15 In the present invention the detergent composition is preferably a dishwashing detergent composition. The dishwashing detergent composition may be a solid composition or a liquid composition. 20 Example compositions are provided in the below tables, for both solid and liquid compositions. Table 11: Dishwashing detergent composition (solid) Ingredients Tablets wt.% Tablets 2 wt.% Powder wt.% Bleach catalyst (of this invention) 0.001-0.5 0.001-0.5 0.001-0.5 Bleach activator 0-5 1-2 Oxygen-based bleaching agents 10-20 15-40 5-10 Surfactants <5 <5 1-5 Builders (Alkali silicates &carbonates) 5-30 0-55 50-85 Builders (Organic sequestrants) 0-45 0-45 Builders (Polycarboxylates) 2-7 <5 Colourants <1 <1 <1 Enzymes <1 0-10 1-3 Enzyme coating (e.g., NaCI) 1-10 1 Fragrance <0.5 <1 <1 Glass protectors, silver protectors 0-1 Lime scale inhibitor 0-10 Bulking agents balance to 100% Table 12: Dishwashing detergent composition (pods or capsules) 15 09 25 Ingredients wt.% Bleach catalyst of the present invention 0.001-0.5 Bleach activator (TAED) 0.5-2.5 Chelating agents (e.g. GLDA) 28-32 Sodium carbonate 30 Sodium percarbonate 12-15 Builders (e.g. PESA, Polyepoxysuccinic acid sodium) 5-10 Surfactants (e.g. Linear fatty alcohol ethoxylate) 4-6 Sodium sulfate 2-3 Enzymes 1-2 Solvents (e.g. Glycerol) 0.2-2 Glasse protectors (e.g. Zinc citrate) 0.3-0.6 Fragrances <0.5 Polyvinyl alcohol (pods or capsules water soluble film) 2-3 Compositions of the present invention may comprise the detersive surfactant, an optional oxidising agent, and an optional breach activator. 5 Specifically, whilst the presence of an oxidative bleach is required for the bleach catalyst of the present invention to act as a catalyst, the detergent system can be provided in component form, such as in the well-known Baukasten system and are therefore not necessarily mandatory. In an alternative embodiment, the present invention provides a bleaching composition comprising 1 10 to 50 wt.% of an oxidative bleach, preferably from 5 to 20 wt.%, more preferably of 8 to 16 wt.%, and from 0.001 to 5 wt.%, preferably 0.01 to 2 wt.%, of one or more bleach catalysts of the present invention, as defined below. In the present invention, the relevant materials are: 15 Oxidative Bleach In embodiments of the present invention, suitable oxidising agents may be selected from sodium percarbonate, sodium perborate, sodium perphosphate, sodium hypochlorite, hydrogen peroxide, 20 sodium dichloroisocyanurate (NaDCC), sodium chlorite, potassium monopersulfate (MPS), sodium carbonate peroxyhydrate, sodium persulfate, or a combination thereof. 15 09 25 In most preferred embodiments of the present invention, the oxidising agents may be sodium percarbonate or sodium perborate. In the most preferable embodiments, the oxidising agent is sodium percarbonate. 5 These oxidising agents are most preferably used in a solid composition. In liquid compositions, hydrogen peroxide may be incorporated directly into the composition. Bleach activator 10 Compositions of the present invention may comprise a bleach activator. The bleach activator enables some of the oxidative bleach to be provided as other activated (i.e., lower temperature active species) in addition to the catalytically mediated oxidation of the bleach catalyst of the present invention. This enables species such as peracids to be created during a washing process 15 (such as after dissolution of a dishwashing powder detergent. Some suitable bleach activators are: Tetraacetylethylenediamine (TAED); Tetraacetylglycoluril (TAGU); Tetraacetylhexanediamine (TAHD); N,N,N',N'-Tetramethyl-6-dodecylamidinouronium chloride (DADMAC); N,N,N',N'-Tetrabenzyl-6-dodecylamidinouronium chloride (BADMAC); N,N,N',N'-20 Tetrabenzyloxycarbonyl-6-dodecylamidinouronium chloride (BODMAC); N,N-Diacetyl-4,5-diazafluoren-9-one (DADHF); N,N'-Diacetyl-4,5-diazafluoren-9-yl peroxybenzoate (DADPA); 1,5-Diacetyl-2,4-dioxohexahydro-l,3,5-triazine (DADHT) and N,N-Diacetyl-3,5-dimethyl-l,4-dioxohexahydro-l,3,5-triazine (DADHT-DM). 25 The preferred beach activator is TAED for use in the present invention. The detergent composition of the present invention may also include a sequestrant. The undesired decomposition of peroxides species can occur when the water used for a detergency 30 operation comprises transition metals in the water supply. There is therefore a balance to be made between removing those unwanted transition metal ions and removal of the transition metal iron of the bleach catalyst of the present invention. It has been surprisingly found that a number of common sequestrants, such as used up to a one-to-35 one rate ratio with the catalyst of the present invention in a detergent composition of the present invention may not hinder the catalyst of the present invention significantly. Relevant sequestrants are: Ethylenediaminetetraacetic acid (EDTA); Nitrilotriacetic acid (NTA); Diethylenetriaminepentaacetic acid (DTPA); Hydroxyethyl ethylenediaminetriacetic acid (HEDTA); 40 Diethylene glycol monobutyl ether-N,N-diacetic acid (DGBE-NDA); l-Hydroxyethylidene-1,1-diphosphonic acid (HEDP); Aminopolycarboxylic acids (APCA) derivatives, such as iminodisuccinic acid (IDS); Methylglycinediacetic acid (MGDA); Gluconic acid. The present invention is particularly beneficial in automatic dishwashing compositions. The present 45 invention particularly where providing slower dissolution distributes catalysts into solution a later 15 09 25 stage in the washing cycle. This is because progressive dissolution supplements catalyst which has previously bee solubilised but has lost activity. The catalyst of the present invention is therefore advantageous over or a supplement to current bleach catalysts (chelates) in providing an alternative profile of action in a washing process, in particular an automatic dishwashing process. 5 The present invention is particularly beneficial in automatic dishwashing compositions. The present invention particularly where bleaching hydrophobic surfaces such as plastics plates and bowls enable better surface bleaching (likely due to hydrophobicity) and so difficult to remove stains, such as curry stains on plastics bowls may be improved. 10 In the present invention the detergent composition may be a laundry detergent composition, such as includes fabric softeners, whitening agents, pre-treatment agents as well as conventional solid, liquid, gel, pouch detergent compositions heavy duty, light duty 'whites' and 'colours' detergent compositions. 15 In the present invention the detergent composition is preferably a fabric washing detergent composition is selected from one or more of a laundry detergent, a laundry fabric softener, a bleach, or a booster laundry aid (such as whitening agent). 20 In the present invention the detergent composition preferably further comprises a proteolytic enzyme and the bleach catalyst comprises an amide linkage. It has been found that some degree of hydrolysis of the bleach catalyst can occur thus generating additional species for absorption. This is particularly useful where the physical form of the one hydrolysed bleach catalyst chelate is convenient for dosage, such as a physical form where hours the hydrolysed bleach catalyst chelate visor species which will 25 otherwise be volatile or at least present in a liquid form on suitable for a given form of delivery. This is particularly relevant with pouch type detergents were the liquid form of the bleach catalyst can act as a plasticiser and we can such pouches, particularly pouches intended for dissolution. The detergent composition of the present invention preferably further comprises a lipolytic enzyme in 30 the bleach catalyst comprises an ester linkage. It has been found that some degree of hydrolysis of the bleach catalyst chelate can occur thus generating additional species for absorption. This is particularly useful where the physical form of the one hydrolysed bleach catalyst chelate is convenient for dosage, such as a physical form where hours 35 the hydrolysed bleach catalyst chelate visor species which will otherwise be volatile or at least present in a liquid form on suitable for a given form of delivery. This is particularly relevant with pouch type detergents were the liquid form of the bleach catalyst can act as a plasticiser and we can such pouches, particularly pouches intended for dissolution. 40 In the present invention the bleach catalyst preferably comprises a linker L, m is 2 or more and X' or X" is O of NH to provide said amide or ester linkage. This enables hydrolysis as mentioned above, particularly in combination with enzymes, but also when present in a high pH, such as of a pH from 8 to 10 were, during washing the bleach catalyst can hydrolyse giving rise the aforementioned benefits. The detergent composition of the present invention may be in the physical form of the detergent composition is a powder (granulate), liquid, a gel, a pouch, a tablet, or solid sheet. Preferably the physical form is as a solid. This is particularly so with bleach catalysts where m is 3 or 5 more and L is a polymer. This provides a bleach catalyst in a solid form compatible with other solids and not subject to hydrolysis in the undiluted state, when dilated such as for use during washing the detergent composition components, such as enzymes or pH creating agents can give rise to hydrolysis releasing bleach catalyst into the washing composition. 10 Detergents compositions representative of the present invention All figures are % by weight (wt.%). 15 09 25 Table 13: Laundry powder composition Ingredients Conventional Compact Anionic and non-ionic surfactant 8-15% 10-30% Builders 20-50% 20-40% Cobuilders 1-5% 1-7% Bleaching agents 10-25% 10-20% Bleach activators 1-3% 2-8% Antiredeposition agents 1% 1% Corrosion inhibitors 2-6% 2-6% Bleach Stabilizers 0-1% 0-1% Bleach catalyst of the present invention 0.001-0.5% 0.001-0.5% Foam regulators 0.1-1% 0.1-2% Enzymes 0.3-1% 0.5-2% Minors, water Balance to 100% Balance to 100% Bulk density, g / L 500-650 600-900 Table 14: Detergent tablet composition Ingredients Zeolite-based Phosphate-based Surfactants 13-18% 15-18% Bleaching agents 13-15% 12-16% TAED 3-7% 4-7% Bleach catalyst of the present invention 0.001-0.5% 0.001-0.5% Zeolite 15-30% - Sodium triphosphate - 25-45% Layered silicate 0-9% 0-9% Sodium polycarboxylate 2-3% 2% Disintegrants 5-17% 0-12% Enzymes 2-4% 1-3% Minors, water Balance to 100% Balance to 100% Bulk density, g / L 500-650 600-900 Table 15: Laundry powder composition Ingredients Homogeneous Structured Anionic surfactants 7-18% 10-25% Non-ionic surfactants 15-30% 6-10% Soaps 10-25% 4-8% Builders 0-5% 15-30% Solubilisers 0-12% 0-5% Alcohols 5-12% 0-5% Bleach catalyst of the present invention 0.005-1.0% 0.005-1% Enzymes 0-2.5% 0-1.5% Minors, water Balance to 100% Balance to 100% 15 09 25 Table 16: Fabric washing bleach detergent composition Ingredients Powder Liquid Anionic surfactants 5-15% 2-10% Non-ionic surfactants 0-1% 3-5% Builders 60-75% - Bleach 3-15% 3-4% Bleach catalyst of the present invention 0.001-0.5% 0.001-0.5% Filler 5-20% - Enzymes 0-1% - Minors, water Balance to 100% Balance to 100% A particularly significant component of the invention is the preservation of the active component prior to use. Bleaching compositions are typically distributed in concentrated form which must be capable of being stored for, typically, many months whereas in a washing situation bleaching action is required in a relatively short time and particularly relevant to bleach catalysts at a low temperature. There is 10 therefore a problem of providing a delivery mechanism for oxidative bleach catalysis. Carriers Oxidative bleaching catalysts are used in a variety of detergent compositions and particularly in 15 automatic dishwashing or fabric washing detergent compositions. Whilst oxidative bleaching catalysts may be incorporated in a fabric washing detergent composition this does not guarantee that the oxidative bleaching catalyst will either remain stable over time, given that fabric washing compositions are typically prepared having a pH greater than pH 7, often at a pH of approximately 10. There is therefore a need for detergent compositions compatible with environmentally acceptable oxidative 20 bleaching catalysts. 15 09 25 Further, particularly in concentrated and granular detergent compositions, compositions are typically provided to an end user for use as a diluted or dissolved solution, the pH that an oxidative bleaching catalyst is exposed to prior to use can be particularly high and this can give rise to issues of storage stability. There is therefore a need for improved delivery compositions compatible with 5 environmentally acceptable oxidative bleaching catalysts, particularly those structures defined in this present application. Similarly, whilst oxidative bleaching catalysts may be incorporated into fabric washing detergent compositions this does not guarantee that the oxidative bleaching catalyst will absorb onto a fabric 10 being washed. The function of a detergent composition is to absorb on the surfaces of fabrics and preferentially adhere, such that oils and other residues are removed. This is carried out by the means of surfactants, surfactants typically being classified as anionic, non-ionic, and cationic. There is therefore the challenge of formulating a fabric washing detergent composition to incorporate an oxidative bleaching catalyst such that the oxidative bleaching catalyst can remain absorbed on a fabric 15 surface after a washing process, washing process typically being followed up by a rinsing process. There is therefore a need for a fabric washing detergent composition capable of delivering environmentally acceptable oxidative bleaching catalysts during a washing process and giving them in place after such a process. 20 Therefore, there is a need for delivery compositions which enable environmentally acceptable oxidative bleaching catalysts, particularly those structures defined in the present application which provide, typically delayed, release of the oxidative bleaching catalyst at a point in a method of washing were the oxidative bleaching catalyst has a higher probability of absorption onto a fabric. Alternatively, particularly rapid release of the oxidative bleaching catalyst may also be advantageous as the oxidative 25 bleaching catalyst can absorb one fabric before significant concentration of surfactant, for example, is present in a washing method so as to compete with the oxidative bleaching catalyst for absorption onto a fabric. Fabric washing detergent compositions are provided in a number of different formats, such as 30 compositions relevant for hand washing, machine washing, uncoloured garments and coloured garments. Compositions which provide an oxidising agent and widely used, and these can also give rise to stability problems regarding environmentally acceptable oxidative bleaching catalysts, such as those structures defined in the present application. There is therefore a need for delivery compositions which mitigate or ameliorate issues caused by oxidising agents in fabric washing detergent 35 compositions. The aforementioned problems are particularly present regarding environmentally acceptable oxidative bleaching catalysts as these structures are often chemically complex, present in small amounts and therefore inherently of high surface area to volume in a composition and specifically to 40 environmentally acceptable compositions often have labile groups intended to be degraded so as to provide biodegradability, such groups are typically more labile in the presence of a high pH, oxidising agent or combinations thereof. Further, due to the typically low levels of oxidative bleaching catalyst used in detergent compositions, such as levels as low as 0.01% is important that the oxidative bleaching catalyst is not present in high 45 concentrations, such as individual granules, since this can give rise to uneven distribution, particularly 15 09 25 if exacerbated due to settling of a granular mixture, for example, during transportation. There is therefore a need for delivery compositions which enable even distribution, along with other relevant detergents ingredients into a detergent composition, particularly a fabric washing detergent composition and in particular a granular, solids fabric washing detergent composition. 5 There is therefore a need for a delivery composition to enable an environmentally acceptable beach catalyst to be incorporated into a composition which is storage stable yet also effective in use. A solid or solid solution in the form of a particle or sheet, the composition comprising from 1 to 50% 10 of the bleach catalyst, from 1 to 50% of a water-soluble organic polymer and optionally an inorganic solid in the form of an alkali metal salt of from 1 to 98% the bleach catalyst comprising a compound (L) as defined below as the ligand of a transition metal element (M), the ligand being a compound (L) of structural formula 1 as presented below. 15 The catalyst delivery composition of the present invention includes, a chelate comprising a compound (L) as defined below as the ligand of a transition metal element (M), the chelate being in solid form either as a solid or in solid solution in the form of a particle or sheet the composition comprising from 1 to 50% of the bleach catalyst, from 1 to 50% of a water-soluble organic polymer and optionally an inorganic solid in the form of an alkali metal salt of from 1 to 98%. All percentages being by weight. 20 The transition metal element M is preferably Mn, more preferably in the 2+ oxidation state(Mn(ll)). The catalyst delivery composition preferably has an in-use pH of the catalyst delivery composition is in the range from pH 8 to 10. This is defined by the pH of a 10g / l solution of the delivery composition. The present invention includes a detergent composition comprising the catalyst delivery composition. 25 The detergent composition is preferably a dishwashing composition. The present invention in addition to providing an alternative bleach catalyst also provides specific advantages, particularly relevant to dishwashing detergent compositions. 30 Specifically, bleach catalysts forming a component of the present invention with the detersive surfactants are, in general, more hydrophobic and, in general less water-soluble than the most prominent corner used oxidative bleaching catalyst, MnMe3-TACN, Bis(N,N',N"-trimethyl-l,4,7-triazacyclononane)-trioxo-dimanganese (IV) di(hexafluorophosphate) monohydrate, otherwise known as Dragon. This gives rise to two advantages in detergent compositions, namely that the catalyst in the 35 form of the bleach catalysts can dissolve progressively during a detergency operation, such as dishwashing and therefore provide a constant level of catalyst rather than a high level at the beginning of a wash, which is particularly the coldest, with decreasing activity during the wash. This is facilitated by the presence of surfactant to enable the surface of the bleach catalyst, in a solid state, to be whetted and thereby facilitate dissolution kinetics. 40 A further advantage is that the hydrophobicity of the bleach catalysts provides additional adsorption onto hydrophobic surfaces, such as greasy surfaces, enabling those services to be oxidised and in conjunction with associated factors for removal into the bulk of the washing liquor provides improved detergency. 45 It is therefore preferred that the delivery composition of the present invention comprises a surfactant. 15 09 25 In the present invention the water-soluble organic polymer is preferably used to encapsulate the bleach catalyst or to act as a solvent to provide a solid solution of the bleach catalyst, thus providing 5 controlled release and improved stability. Water-soluble organic polymers of the present invention are: Polyvinyl alcohol (PVA), Polyvinylpyrrolidone (PVP), Cellulose derivatives, such as hydroxypropyl methylcellulose (HPMC) or carboxymethyl cellulose (CMC), Polyethylene glycol (PEG). The preferred water-soluble organic polymer is PVA. PVA is highly water-soluble, allowing for the easy 10 dissolution of the encapsulating film during the dishwashing process. The PVA may be preferably present as a film. A PVA film may be used to provide sachets or packaging for other components, such as in, most preferably, a source of oxidative be shuts as a jumper oxide, for example sodium percarbonate. The use of PVA particularly a PVA film can enable controlled release of the encapsulated ingredients. 15 It has been found that the water-soluble organic polymers provide greater storage stability of the detergent delivery composition of the present invention and specifically of the bleach catalyst contained therein. The most preferred for this purpose is PVA. 20 The preferred molecular weight of the water-soluble organic polymer is in the range PVAs with molecular weights ranging from 10,000 to 200,000 Da as measured using size exclusion chromatography using a polystyrene standard. The most preferred molecular weight range is 50,000 to 150,000 Da, which enables rapid water 25 solubility but effective protection for the bleach catalyst against degradation, particularly in high pH storage environments. The catalyst delivery composition may preferably be in granular form. 30 Creating granules of bleach catalyst, may be achieved by one or more of the following granulation techniques: Spray Drying: 35 In this method, a solution or suspension containing the bleach catalyst is atomized into fine droplets and sprayed into a drying chamber. This is preferably carried out as a co-solution with an alkali metal salt. The droplets are rapidly dried using hot air or a heated gas, resulting in the formation of granules. 40 The process can be optimized by selecting appropriate drying conditions, such as temperature, airflow, and droplet size, to obtain granules of the desired size and properties. Fluid Bed Granulation: 15 09 25 Fluid bed granulation involves the formation of granules by spraying a solution or suspension of the manganese-based catalyst onto fluidized particles. The fluidized particles act as nuclei, and the catalyst solution or suspension is sprayed onto them, 5 leading to the formation of granules through the agglomeration of the particles. The process is typically carried out in a fluid bed granulator, where heated air is used to fluidize the particles and facilitate drying and granule formation. Extrusion: 10 Extrusion is a technique commonly used for the formation of cylindrical or pellet-shaped granules. In this method, a mixture of the manganese-based catalyst and suitable excipients, such as binders or fillers, is forced through an extruder. 15 The extruder applies pressure and shearing forces to the mixture, leading to the formation of cohesive granules. The extrudates are then dried and further processed if needed to obtain the desired granule size. 20 Wet Granulation: Wet granulation involves the formation of granules by wetting the bleach catalyst and other excipients, such as an alkali metal salt with a liquid binder in the form of a solution of water-soluble organic 25 polymer. The mixture is then agitated or kneaded to form cohesive wet granules. The wet granules are subsequently dried, sieved, and processed as required to obtain granules suitable 30 for use in detergent compositions. It is important to note that the selection of the granulation method will depend on factors such as the properties of the catalyst and other ingredients, the desired granule characteristics (size, shape, density), and the processing capabilities available. Process optimization, including binder selection, 35 drying conditions, and particle size control, may be necessary to achieve the desired granule properties. Fabrics 40 Bleach catalysts of the present invention may be used in fabric manufacturing. Bleach catalysts of the present invention may be used in finishing processes for cotton. Preferably in the treatment of griege (loom-state) cloth into finished fabric. 45 Bleach catalysts of the present invention may be used in melt spinning thing synthetic fibres. Table 16: Representative raw cotton bleaching composition Ingredient Amount Hydrogen Peroxide (H2O2) 10-25% Bleach catalyst of the present invention 0.001-0.5% Sodium Hydroxide (NaOH) 1-5% Sodium Metasilicate (Na2SiO3) 1-5% Sodium Hypochlorite (NaOCI) 0.05-0.5% Sequestering Agent (Sodium Hexametaphosphate) 0.5-2% Stabilizer (Sodium Phosphate) 0.1-1% Balance to 100% water 15 09 25 Paper 5 Bleach catalysts of the present invention maybe used in paper manufacturing. Preferably during "wet" manufacturing processes as detergent compositions. Bleach catalysts of the present invention may be used in paper finishing as detergent compositions, 10 for example to treat cellulose fibre before paper manufacture. Table 17: Representative paper pulp bleaching composition Ingredient Amount Hydrogen Peroxide (H2O2) 3-15% Bleach catalyst of the present invention 0.001-0.5% Chelating agent (e.g. EDTA) 0.1-2% Sodium Hydroxide (NaOH) 0.1-2% Sodium Metasilicate (Na2SiO3) 0.1-2% Sodium Hypochlorite (NaOCI) 0.005-0.5% Stabilizer (Sodium Silicate) 0.1-1% Balance to 100% water Cosmetics 15 Bleach catalysts of the present invention may be used in conjunction with emollient to provide cosmetics compositions as detergent compositions. Bleach catalysts of the present invention may be used to produce detergent and bleaching 20 compositions, for example as hair bleaching products, teeth whitening products, nail bleaching treatments or spot correctors. Oxidative bleaches, such as hydrogen peroxide-based formulations, are widely used in hair bleaching products to lighten the colour of the hair. These products are used to achieve highlights, balayage, and overall hair lightening effects. Such a composition typically comprises a source of hydrogen peroxide, a surfactant and the bleach catalyst of the present invention. Table 18: Representative hair bleaching composition Ingredient Amount Hydrogen Peroxide (H2O2) 6-12% Bleach catalyst of the present invention 0.001-0.5% Ammonium Persulfate ((NH4)2S2O8) 20-30% Potassium Persulfate (K2S2O8) 20-30% Sodium Metasilicate (Na2SiO3) 1-5% Sodium Carbonate (Na2CO3) 1-3% Kaolin Clay 1-3% Conditioning Agent 1-3% Stabilizer (Sodium Phosphate) 0.5-2% Balance to 100% water 15 09 25 Oxidative bleaches, typically containing hydrogen peroxide or carbamide peroxide, may also be utilized in teeth whitening products. These products help remove stains and discoloration from the teeth. Such a composition comprises a source of hydrogen peroxide, a surfactant and the bleach catalyst of the present invention. 10 Oxidative bleaches may also be employed in nail bleaching treatments designed to lighten and brighten discoloured or stained nails. These treatments help restore the natural colour and appearance of the nails. 15 In spot corrector products, which are typically used to address specific areas of concern such as dark spots, age spots, or blemishes, oxidative bleaches may be used to help fade or lighten the affected areas. Such a composition comprises a source of hydrogen peroxide, a surfactant and the bleach catalyst of the present invention. 20 The advantages of the present invention in cosmetics are that they provide an increase bleaching of cosmetics whilst retaining low levels of hydrogen peroxide, in an environmentally acceptable format whilst also reducing skin irritation. The present invention may be exemplified by a bleaching booster composition which is added, such as 25 a separate addition on preparing a washing liquor. The composition consisting of the detergent composition of the present invention, preferably anionic surfactant and bleach catalyst, The surfactant enabling efficient dispersion of the catalyst so as to avoid localised bleaching, such as may give rise to spots (such as white spots) on objects to be bleached. 30 The bleach catalyst in-use acts as a catalyst for oxidative bleaching. Definition of the ligand of the bleach catalyst of the present invention. The ligand of the present invention required for forming the bleach catalyst of the present invention which is used in the detergent composition of the present invention is selected from one or 15 09 25 General 5 In the event that a compound of the present invention appears to disclose a noncanonical valence (such as a variance of 5 carbon) instructor should be interpreted by the additional deletion of protons to provide a canonical valence. 10 For the purposes of the present description the compounds of the present invention may also be described as ligands even if not actually chelating a metal ion. EXAMPLES 15 Example 1 -Procedure and composition The liquid laundry detergent formulations of the cleaning tests in the subsequent Examples were prepared having the generic formulation as described in Table 27 with the bleach catalyst and were prepared by standard liquid laundry formulation preparation procedures. 20 Control, conventional bleach catalysts not being biodegradable include; 2,2'-Stilbenedisulfonic acid, CAS number 16090-02-1, 4,4'-Bis[(4-anilino-6-morpholino-l,3,5-triazin-2-yl)amino]stilbene-2,2'-disulfonic acid disodium salt (example commercial names Blancophor BBH, DAS 1 or DMA-X) 25 Table 19: Generic formulation Ingredient wt.% Linear alkyl benzene sulfonate 8.0 Sodium lauryl ethoxysulfate 2.0 Non-ionic surfactant 4.0 Sodium percarbonate 15.0 Bleach catalyst 0.2 Deionized water to 100 Example 2 - Cleaning methodology The primary cleaning performance of the liquid laundry detergent formulations of the Examples were 30 assessed in a Terg-o-tometer of SR Lab Instruments (4 x 1 L vessels) agitated at 90 cycles per minute with the conditions noted in Table 28. Fabric swatches are of 5cm square. Table 20: Cleaning performance conditions Parameter Setting Temperature 25 °C Water hardness 300 ppm, Ca / Mg = 2 / 1 Fabric Types Stained Cotton 400 (3 in each vessel) Stains Tea, Curry, Clean cotton Wash time 16 minutes Rinse time 3 minutes Liquid laundry detergent dosage 0.5 g / L Example 3 - Bleach Catalyst UV-Vis test method 15 09 25 Bleaching efficiency of prepared catalyst complexes was tested by monitoring the reduction in 5 absorbance at 630nm of a naphthol blue black dye solution by UV-Vis. Four stock solutions were prepared before testing; i) pH 10.5 buffer solution prepared by adding a 0.5M sodium bicarbonate solution to IL 0.5IVI sodium carbonate solution until the desired pH is achieved; ii) 0.75M H2O2 comprising of 72.9g 35% H2O2 made IL volume with D.L water; iii) Naphthol blue black dye solution comprising of 0.028g naphthol blue black made to IL volume with D.l. water and iv) a lmmol solution 10 of the catalyst with respects to Mn metal stoichiometry made up in D.l. water. To measure bleaching performance 20ml of the prepared 0.75M H2O2 solution was charged to a 1ml cuvette, followed by 20ml of the lmmol catalyst solution. The cuvette was then placed in the UV-Vis apparatus and measurement was started. 1ml of the naphthol blue black dye solution and 2.25ml of 15 buffer solution were then charged sequentially. Percentage bleaching was calculated as the percent reduction in absorbance at 630nm 0.5h from the point of highest absorbance. The maximum observed rate was taken from the point of greatest gradient observed on the UV-Vis trace. 20 Table 21: Comparison to existing catalysts Catalyst Total bleaching 0.5h Max. obs. Bleach rate MnCl2.2H2O 13% -0.005 Mn(OAc)2.4H2O 55% -0.002 Mn(ll) oxalate 57% -0.025 MnMe3-TACN prepared as per literature 75% -0.100 Formula (II) complex 75% -0.244 Table 22: Ligand ratio comparison (chloride counterion) Formula (II): Mn Total bleaching 0.5h Max. obs. Bleach rate 1 49% -0.180 2 68% -0.277 3 72% -0.280 Table 23: Mn counterion comparison Mn counter ion Total bleaching 0.5h Max. obs. Bleach rate cr 68% -0.277 co3_ 34% -0.006 AcO" 75% -0.244 CI4O’ 40% -0.053 F6P- 79% -0.085 15 09 25 Table 24: Structure variations Ligand structure Total bleaching 0.5h Max. obs. Bleach rate 75% -0.244 86% -0.308 >30% <-0.03 59% -0.032 JLX >30% <-0.03 1 io —^OH 66% -0.124 >30% <-0.03 >30% <-0.03 >30% <-0.03 >30% <-0.03 °H —^*x ex >30% <-0.03 ^x / ^Qn >30% <-0.03 1 XXc YXl >30% <-0.03 >30% <-0.03 35% -0.153 R 7 53% -0.092 >30% <-0.03 15 09 25 As can be seen above, bleach catalysts of representative ligands of the present invention are effective in promoting oxidative bleaching. 5 Example 4 - Bleach Catalyst Stain Removal Test Standard pre-stained melamine tiles (DM-14, DM-11, DM-81, DM-82, DM-51, and DM-62) from the Center for Test materials (CFT, The Netherlands) were used for this test to demonstrate stain removal in automatic dishwashing application. 10 Bleach performance test by stain removal from pre-stained tile pieces was achieved by dissolving 4.2g sodium carbonate and 0.8g sodium bicarbonate in IL in deionized water at 40°C. When testing catalysts in solution, 5mL of a prepared lmmol catalyst solution in deionized water was 15 charged to the mixture; and for solid catalyst testing a mass equivalent to 5mmol catalyst was charged directly to the stirred mixture. The stain test plate of interest was then half submerged in the stirred mixture before adding 5ml of a 0.75M H2O2 solution. Test pieces were submerged for a total of 10 minutes from the addition of H2O2 20 before rinsing with deionised water and allowed to dry in air. Tables 29 and 30 show the performance of the catalyst when charged as a solution (Table 29) or a as a solid (Table 30), in comparison with no catalyst, and other catalysts, such as Dragon. Table 25: Catalyst charged as a solution CFT Stain tile reference No cat. Blank Mn(0Ac)2 Dragon H DM14- highly discriminative tea V. Poor Poor V. Good V. Good V. Good DM11-tea V. Poor Poor Good Good Good DM81 - coffee V. Poor Poor Good Moderate Good DM82-espresso V. Poor Poor Moderate Moderate Moderate DM51-red wine V. Poor Poor Good Good Good DM62 - curry V. Poor Poor Poor Moderate Moderate Table 26: Catalyst charged as a solid Stain No cat. Blank Mn(OAc)2 Dragon DM14- highly discriminative tea V. Poor Poor V. Good Excellent Excellent DM11-tea V. Poor Poor Good Good Good DM81 - coffee V. Poor Poor Good Good V. Good DM82-espresso V. Poor Poor Moderate Good Good DM51-red wine V. Poor Poor Good V. Good V. Good DM62 - curry V. Poor Poor Poor V. Good V. Good 15 09 25 As can be seen in the above tables, it is clear that the presence of a catalyst enables bleaching to take 5 place and its ligand is required, beyond a simple anion in conjunction with the manganese to provide any bleaching effect. Commercially available catalysts such as Dragon (MnMea-TACN, Bis(N,N',N"-trimethyl-l,4,7-triazacyclononane)-trioxo-dimanganese (IV) di(hexafluorophosphate) monohydrate) provide effective bleaching and the ligands of the present invention provide improvements on this bleach catalyst's activity, as demonstrated as above. Particularly, the improvements are striking when 10 a solid catalyst formulation is used. Further testing of Formula (II) with DM14 stained plates was conducted using the above method, with the performance quantified by colorimetric analysis using L*a*b* values to calculate the stain removal index (SRI), which uses the below formula: 15 SRI = 100 - AE AE = V(it - io)2 + (at - a0)2 + (*t - ^o)2 t = clean tea-stained tile 0 = unstained tile 20 Tables 27 and 28 show the data from this analysis, and the associated stain removal indices, comparing the performance of the catalyst when charged as a solid or solution in comparison with the commercial benchmark, Dragon, in the absence of (Table 31) or in the presence of (Table 32) TAED. 25 Table 27: Comparison of Formula (II) solid and solution loaded in the bleaching of DM14 stains in the absence of TAED. Sample L* a* b* SRI Average S.D. Unstained 92.7 -0.9 2.3 Blank 86.8 -0.2 14.4 86.5 86.2 0.41 86.8 -0.1 14.3 86.6 86.8 -0.1 14.3 86.6 15 09 25 87.2 0.3 15.3 85.8 87.3 0.3 15.3 85.9 87.3 0.3 15.4 85.8 Dragon 89.5 -0.3 12.2 89.6 89.2 0.35 89.9 -0.3 12.5 89.4 89.8 -0.4 12.5 89.4 87.9 -0.1 12.2 89.0 87.9 0 12.5 88.7 88.0 -0.1 12.3 88.9 Solid Loaded 90.2 -0.6 12.9 89.1 88.1 0.59 88.3 0.2 13.8 87.6 88.9 0 13.2 88.4 88.3 0.1 13.5 87.9 88.2 0.2 13.5 87.9 87.7 0.2 13.7 87.5 Solution Loaded 87.8 -0.1 14.1 87.2 87.1 0.19 88.2 0.0 14.1 87.3 88 0.1 14.4 87.0 87.6 0.1 14.2 87.0 87.2 0.1 14.2 86.9 87.5 0.1 13.9 87.2 The use of a solid catalyst charge in place of a stock aqueous solution gives a profound increase in the performance of Formula (II), with SRI values approaching that of the commercially available Dragon catalyst. The above bleaching method was repeated with the addition of 0.25g of TAED to the bleaching solution. Table 28: Comparison of Formula (II) solid and solution loaded in the bleaching of DM14 stains in 10 the presence of bleach activator TAED. Sample L* a* b* SRI Average S.D. Unstained 92.7 -0.9 2.3 Blank 88.3 -0.3 12.2 89.1 89.2 0.37 88.3 0 12.9 88.5 87.9 -0.3 11.6 89.5 88.1 -0.2 11.9 89.3 88 -0.2 11.8 89.4 88.1 -0.2 11.9 89.3 Dragon 91.1 -0.7 11.1 91.1 91.3 0.27 91.3 -0.7 11 91.2 88.7 -0.5 9.7 91.6 15 09 25 88.4 -0.3 9.7 91.4 89 -0.3 9.7 91.7 88.8 -0.2 10.3 91.1 Solid Loaded 89.6 -0.4 11.5 90.3 90.9 0.67 89.6 -0.3 11.4 90.4 88.6 -0.6 9.7 91.5 88.6 -0.6 9.5 91.7 89.8 -0.3 10.8 91.0 89.7 -0.3 10.7 91.1 88.5 -0.2 11.4 90.0 88.7 -0.2 11.5 89.9 89.8 -0.3 11 90.8 90.1 -0.3 11.1 90.8 90.6 -0.5 10.2 91.8 90.4 -0.5 10.4 91.6 Solution Loaded 90.1 -0.3 11.3 90.6 90.2 0.69 90.2 -0.2 11.4 90.5 90.4 -0.4 11.3 90.7 90.3 -0.4 11.2 90.8 90.3 -0.2 12.9 89.1 90.5 -0.2 12.4 89.6 Table 28 shows that with the addition of a bleach activator, such as TAED, the solid loading of Formula (II) is capable of matching the performance of the commercially available bleach catalyst, Dragon. 5 Example 5 -Automatic Dishwasher Testing The bleach catalysts were assessed in a standardised IKW test to assess the potential to be used in a commercial automatic dishwasher (ADW). The IKW (Industrieverband Kbrperpflege- und Waschmittel e.V.) has published numerous recommendations for the quality assessment of detergents and cleaners. 10 The bleach catalyst selected was the Mn-Complex of Formula (II), with both a broad particle size distribution (PSD) and a narrow PSD, which was obtained by sieving the former to remove small particle sizes through a sieve stack, isolating the 250-500 pm range, and were present in the formulations at 0.05 wt. %, with and without TAED at 2 wt.%. These were compared to the commercial 15 Dragon bleach agent, in formulations of 0.025 wt.% with and without TAED at 2 wt.%. The ADW formulations were prepared on the below base formula, where they key elements of the ADW powder contain: chelating agent (such as Na Citrate dihydrate / Sodium Carbonate), low foaming non-ionic surfactant Linear fatty alcohol ethoxylate, chelating agent (provides particle size control of 20 salts, such as Polyacrylate (Sokalan PA 20 from BASF)), alkaline chelating and anti-glass corrosion (such as Sodium Metasilicate), alkaline cleaning agent (such as Sodium percarbonate), degradation of Starches and sugars (such as amylase), degradation of proteins (such as protease), filler (such as Sodium Sulphate) and binder (such as Isomalt). Table 29: Base Formula of ADW Powders 15 09 25 Component Amount (%) Na Citrate dihydrate 20 Sodium Carbonate 25.5 Linear fatty alcohol ethoxylate (Lutensol XP 30) 1 Polyacrylate Sokalan PA25 4 Sodium Metasilicate 4 Sodiumpercarbonate 3 TAED - MnTACN - TSCL (genl) - TSCL(gen2) - Amylase 0.5 Protease 0.7 Sodium sulphate 30 Binder (Isomalt) 11.3 TOTAL 100 To perform a quality assessment of the performance of the bleach catalysts, a standardised method of the IKW test was selected, in which bleachable stains are examined. In this case tea stains were used as the bleachable stains. In addition, to meet IKW requirements, the minimum amount of additional soils were included, which included black tea, milk, starch mix and egg yolk. 10 The IKW test requires the use of teacups, however more accurate numerical quantification was required so additional Tea-stained tiles on melamine DM-14 from CFT were used. The ADW testing was performed in 3 in-line Bosch slimline ADW machines. 15 In each machine three tea-stained CFT (DM-14) tiles were placed in an alternating pattern between three metal plates with egg yolk. Furthermore, there are three beakers with dried milk skin, three glass tumblers and three IKW stained teacups on the top shelf. In the bottom trays of each of the tree machines 1,2 and 3 the following dish wash items were used: 20 serving ceramic plates, and 3 larger ceramic plates soiled with starch. 20 The ADW testing was conducted under the following conditions: Nominal Wash program of 45 °C for Machines 1, 2 and 3, and ballast soil. The machines 1, 2 and 3 were loaded with the identical ADW formula then ran in parallel to achieve more statistical significance, for a wash cycle time of 45 minutes, and a water hardness of 288 mg / L CaCOs. The machines were run in a lab space in a controlled air-25 conditioned 20 °C lab environment. After completion of the wash cycle, the CFT tiles were removed from the ADW machine and dried for an hour in air. The L*a*b* values of three CFT tiles were then measured using a handheld colorimeter. The L*a*b* values were used to calculate the SRI values, which were averaged across the three dishwashers. Table 30: SRI Values determined through ADW testing TAED No cat. Dragon Broad PSD Narrow PSD SRI NoTAED 86.3 88.8 89.3 86.4 With TAED 89.5 91.6 90.0 90.1 15 09 25 5 The data of Table 30 shows that the standard formulation of the broad PSD Formula(ll) Mn-Complex, out-performs the narrow PSD version when used without TAED. When TAED is present, both versions of the Formula (II) Mn-complex (broad and narrow PSD) showed comparable performance. 10 Example 6 - Biodegradation Readily biodegradability is defined as the ability of a product to biodegrade quickly and completely in water (either >70% dissolved organic carbon removal, >60% theoretical carbon dioxide or >60% theoretical oxygen demand, depending on OECD 301A-F test methods) in a 10-day window within 28 15 days. Inherently biodegradability is defined as >20% but <60% biodegradability in water as measured by the same test. The compound of formula (II) is readily biodegradable. It shows similar total biodegradation as Sodium benzoate used as a control for these tests. Figure 3 shows the biodegradation profile of compound of 20 Formula (II) (OECD 301B). In comparison, according to information available on the ECHA website httPs; / / echa.europa.eu / registration:dpssier / " / regjstered-dpssjer / lS878 / 5 / 3 / 2, for the existing Mea-TACN ligand "the percentage biodegradation of the test material was 0 % at the end of the test." (301D 25 method). Despite two of the ligands of invention (formula (11)) being bound to Manganese, the corresponding complex still shows a good degree of biodegradation and is considered to be inherently biodegradable. Figure 4 shows the biodegradation profile of Formula (II) Mn-complex (OECD 301B). 30 In comparison, according to information available on the ECHA website https: / / echa.europa.eu / registration-dossier / - / registered-dossier / 8850 / 5 / 3 / 2, with Dragon™ catalyst, "no biodegradation took place at 10 mg / l in a modified Sturm test (according to OECD 301B)". 35 Cyclic voltammetry was conducted on the complex and identified a reversible single electron transfer corresponding to the oxidation of Mn(lll) to Mn(IV), which is the catalytic mode of action for the complex. Additionally, the voltammetry also identified an irreversible event at a high negative potential, which was accompanied by deposition of material on the Pt electrode. This is expected to correspond to the degradation of the catalyst by dissociation of the ligand from the Mn centre and Mn oxide formation in high pH conditions. Figure 5 shows the proposed mechanism of action for the biodegradation process. The Biowin software used in the present invention for the prediction of biodegradability is part of the 5 Estimation Program Interface (EPI) Suite™ of software available from United States Environmental Protection Agency (EPA). It is a compilation of QSPR models that predict environmentally relevant properties of organic chemicals. Within this software, BIOWIN™ estimates aerobic and anaerobic biodegradability of organic chemicals in aquatic environment using 7 different models. 10 The most relevant parameters to the present invention are the Biowin 3 and Biowin 5 measures. If the Biowin 3 (ultimate survey model) result is >= 2.75 (i.e. "weeks" or faster) and the Biowin 5 (MITI linear model) probability is >= 0.5, then the prediction is YES (readily biodegradable). If this condition is not satisfied, the prediction is NO (not readily biodegradable). For convenience, shown in the table below (Table 31) examples of the structures from the present invention which have similar or higher 15 biodegradability prediction scores than formula (II) and are expected to provide ligand and metal complexes with at least the same inherent biodegradability, which is consistent with actual OECD 301B test described above. 15 09 25 Table 31: Biodegradability predictions based on Biowin Scores Ligand Structure Biodegradability Prediction Very good ^^OH Good O'A Excellent Q-X Moderate n ^OH Excellent 0 o-\ / Good ^'^OH 20

Claims

1. A bleach catalyst comprising at least one metal coordinated to at least one ligand of formula (I) having the structure:15 09 25whereinn is 1 or 2;m is 1 to 4, when the or each R independently represents H; orm is 1 or 2, when the or each R independently represents CH3, C2H5, C3H7, C4Hgor OH, or OR1 wherein R1 represents CH3(CH2)v, wherein v is 0 to 17, which chain may be hydroxy- or alkoxy-terminated, or NR22, wherein:R2 represents H or CH3(CH2)W, wherein w is 0 to 17; orR2 represents alkoxyalkyl; andR' represents H, CH3, CH2CH3, CH(CH3)2, (CH2)yOH or (CH2)yCOOH, wherein y is 0 to 17;R" represents H, CH3, CH2CH3,CH2OH, CH2CH2OH, CH2OCH3or CH2CH2OCH3;R'" represents:H; orC(O)R3, wherein R3 represents(CH2)zR4, wherein z is from 1 to 18 and R4 is H, OH orCOOH; or-R5-R6, wherein R5 represents Ci to C4 alkyl, and R6 represents H, CH3, OH, COOH, OCH3, OCH2CH2OH or OCH2CH2OCH3, or CH(OH)CH2OH.

2. The bleach catalyst according to claim 1 wherein:a. the or each R is H, CH(CH3)2, C(CH3)3, CH2CH3 or OH;b. the or each R is H;c. where the or each R represents NR22, R2 is H or CH3(CH2)W;d. where the or each R represents NR22 and R2 is CH3(CH2)W, w is 0;e. where the or each R represents NR22 and R2 represents alkoxyalkyl, the alkoxyalkyl is hydroxyethyl or hydroxypropyl;f. R is located in positions 4, 5 or 6 of the aromatic ring;g. R' is H;h. R" is H;i. where R'" represents C(O)R3, R3 is (CH2)ZR4;j. R4 is OH; ork. where R'" represents -R5-R6, R5 is methylene.

3. The bleach catalyst of claim 1 or claim 2, wherein the metal is selected from iron (Fe), manganese (Mn), copper (Cu), or cobalt (Co).15 09 254. The bleach catalyst according to claim 3, wherein the transition metal ions is iron(11), iron(l11), manganese(ll), manganese(lll), copper(ll), cobalt(II) or cobalt(III).

5. The bleach catalyst of any one of claims 1 to 4, being a hexadentate complex.

6. The bleach catalyst according to claim 5, wherein the bleach catalyst further comprises one or more further ligands other than those according to claims 1 or 2, optionally wherein the further ligand(s) is or are selected from H2O, carbonate, hydroxide, a halide or an organic acid.

7. The bleach catalyst according to any one of claims 1 to 6, formulated for use as a bleach catalyst, optionally wherein the compound or chelate is formulated for use as an oxidative bleach catalyst.

8. The bleach catalyst according to claim 7 comprising part of a bleach catalyst formulation, wherein the formulation additionally comprise at least one ancillary compound, optionally selected from one or more of surfactant(s), detergent(s), bleach(es), bleach activator(s), carrier compound(s), stabilizer(s) and / or dispersant(s).

9. Use of a bleach catalyst comprising at least one metal coordinated to at least one ligand of formula (I) according to any one of claims 1 to 8 as bleach catalysts.

10. A method for bleach catalysis comprising contacting a bleach catalyst according to any one of claims 1 to 8, with a bleach under conditions effective to allow the compound to enhance a bleaching process.

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