Process for preparation of odorous compounds

Abstract

The present invention relates to a process for the preparation of odorous compounds of formula (I), odorous compounds denoted by formula (I) and the fragrance, flavor and / or deodorizing / masking compositions comprising odorous compounds denoted by formula (I).

Description

[0001] PROCESS FOR PREPARATION OF ODOROUS COMPOUNDS

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to a process for the preparation of odorous compounds of formula (I), odorous compounds denoted by formula (I) and the fragrance, flavor and / or deodorizing / masking compositions comprising odorous compounds denoted by formula (I). In particular, compounds of formula (I) are useful in providing aldehydic, watery, floral, green type notes to perfume, aroma or deodorizing / masking compositions.

[0004] A = -CH2OAC, -CH2OH, -CHO dotted line represents a double or single bond

[0005] R-i is an alkyl or alkylidene group

[0006] Formula (I)

[0007] Here, compounds of formula (I) are selected from any one of its stereoisomers or a mixture of one or more of these stereoisomers. Further, compounds of formula (I) are selected from one of its regioisomers or a mixture of one or more of its regioisomers.

[0008] According to an embodiment of the present invention, Ri is selected from alkyl or alkylidene groups having up to 9 carbon atoms with a linear or branched chain; Ri can advantageously be selected from methyl, ethyl, w-propyl, isopropyl, / / -butyl, isobutyl, w-pentyl, w-hexyl, n-heptyl, n-octyl, n-nonyl, methylidene, ethylidene, propylidene, isopropylidene, butylidene, isobutylidene, pentylidene, hexylidene, heptylidene, octylidene, or nonylidene.

[0009] BACKGROUND OF THE INVENTION

[0010] Increasing limitations on the supply of natural fragrance ingredients have revolutionized the field of synthetic fragrance ingredients. Nowadays, there is an increasing demand for novel odorants / compounds and / or novel fragrance, flavor and / or deodorizing / masking compositions comprising said odorants / compounds.

[0011] Long chain aldehydes are present in many naturally occurring essential oils, which are obtained from various fruits or vegetables. Decanal is found in orange peel whereas octanal also occurs naturally in citrus oils. Unsaturated aldehydes like / ra / / .s-2-decenal and trans -2-dodecenal are present in coriander whereas zra / / .s-4-decenal has aldehydic, orange, floral profile.

[0012] Typically, 4-alkenals are prepared in two steps. In the first step, alkyl magnesium halide is added to an unsaturated aldehyde to afford an allylic alcohol. In the next step, the allylic alcohol obtained in step 1 is subjected to Claisen rearrangement by heating with ethyl vinyl ether or n- butyl vinyl ether to afford the desired 4-alkenal. For example, WO2006133591 discloses synthesis of (E)-3-methylundec-4-enal in two steps: the first step involved reaction between crotonaldehyde and / / -heptyl magnesium bromide to afford (E)-undec-2-en-4-ol which on Claisen rearrangement using / / -butyl vinyl ether in presence of phosphoric acid triethanolamine salt at 170-200 °C led to the desired (E)-3-methylundec-4-enal. These 4-alkenals can be reduced to the corresponding alcohols viz 4-alkenols by treatment with sodium borohydride as depicted in the following scheme.

[0013] W02006133591

[0014] (E)-but-2-enal heptylmagnesium bromide

[0015] (E)-undec-2-en-4-ol catalyst

[0016] 170-200 °C

[0017] Claisen

[0018] Rearrangement

[0019] (E)-3-methylundec-4-enal (E)-3-methylundec-4-en-1 -ol

[0020] Anionic oxy-Cope rearrangement has also been utilized for synthesis of 5-alkenals from 1 ,5- dien-3-ols via [3,3]-sigmatropic rearrangement. Again, these 5-alkenals can be reduced to the corresponding alcohols viz 5-alkenols by treatment with sodium borohydride as depicted in the following scheme.

[0021] Tomooka, Katsuhiko; et al Chemistry Letters (1991), (1), 43-6 KH 18 6

[0022] Ibatullin et al. reported reaction of 3-methyl-3-buten-l-ol with carbonyl compounds on solid surface (SiCh or AI2O3) to afford di and tetrahydropyrans as a mixture of isomeric compounds. Ibatullin et al., Cnem. Heterocyclic Compounds 2Q(2), 155-157, 1990.

[0023] 3-methylbut-3-en-1-ol compound

[0024] X= H, Y= C4H9 X= H, Y= C4H9

[0025] In literature synthesis of individual isomeric compounds having double bond at either carbon 4 or carbon 5 are reported. But none on the reported processes affords mixture of products of formula (I) which have double bond between carbons 4 & 5 (4-en-i somers) or carbons 5 & 6 (5 -en-i somers).

[0026] DESCRIPTION

[0027] The present invention relates to a process for preparation of compounds of formula (I)

[0028] A = -CH2OAC, -CH2OH, -CHO dotted line represents a double or single bond

[0029] R-i is an alkyl or alkylidene group

[0030] Formula (I) as defined in the claims.

[0031] Here, compounds of formula (I) are advantageously selected from any one of its stereoisomers or a mixture of one or more of these stereoisomers. Further, compounds of formula (I) are advantageously selected from one of its regioisomers or a mixture of one or more of its regioisomers.

[0032] According to an embodiment of the present invention, Ri is selected from alkyl or alkylidene groups having up to 9 carbon atoms with a linear or branched chain; Ri can advantageously be selected from methyl, ethyl, w-propyl, isopropyl, / / -butyl, isobutyl, w-pentyl, w-hexyl, n-heptyl, n-octyl, n-nonyl, methylidene, ethylidene, propylidene, isopropylidene, butylidene, isobutylidene, pentylidene, hexylidene, heptylidene, octylidene, or nonylidene. As an example, compounds of formula (I) can be a mixture of two or more, for example four of the following stereoisomers and / or regioisomers wherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain, e.g. an alkyl group with C2 to C9 atoms, or

[0033] For all isomers: trans cis wherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain, e.g. an alkyl group with C2 to C9 atoms and R3 and R4 are selected from H and alkyl groups with a linear or branched chain such that the sum of carbon atoms in R3 and R4 is from 2 carbon atoms to up to 8 carbon atoms. The present invention also relates to a mixture of the following two compounds of formula (I) wherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain, e.g. an alkyl group with C2 to C9 atoms, or wherein A = -CH2OAC, -CH2OH or -CHO and R3 and R4 are selected from H and alkyl groups with a linear or branched chain such that the sum of carbon atoms in R3 and R4 is from 2 carbon atoms to up to 8 carbon atoms.

[0034] The present invention also relates to a mixture of the following two compounds of formula (I) wherein A = -CH2OAC, -CH2OH or -CHO and R3 and R4 are selected from H and alkyl groups with a linear or branched chain such that the sum of carbon atoms in R3 and R4 is from 2 carbon atoms to up to 8 carbon atoms.

[0035] The present invention also relates to a mixture of the following four compounds of formula (I) trans cis wherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain, e.g. an alkyl group with C2 to C9 atoms and R3 and R4 are selected from H and alkyl groups with a linear or branched chain such that the sum of carbon atoms in R3 and R4 is from 2 carbon atoms to up to 8 carbon atoms.

[0036] In an embodiment, there is provided a fragrance, flavor and / or deodorizing / masking composition comprising any of the above formula (I) compound(s).

[0037] Illustrative examples of odorous compounds obtainable by the process of the present invention are a. 3-methyloctan-l-ol b. 3 -methyloctanal c. 3-methylnonan-l-ol d. 3-methylnonanal e. 3 -methyldecan- l-ol f. 3 -methyldecanal g. 3-methylundecan-l-ol h. 3 -methylundecanal i. 3-methyldodecan-l-ol j . 3 -methyldodecanal k. 3 -methyltridecan- l-ol l. 3 -methyltetradecan- l-ol m. 3,6-dimethyloctan-l-ol n. 3,6-dimethyloctanal o. 3,6,7-trimethyloctan-l-ol p. 3,6,7-trimethyloctanal

[0038] Further illustrative examples of odorous compounds obtainable by the process of the present invention are

[0039] 1. 3-methyloct-4-en-l-ol

[0040] 2. 3-methyloct-5-en-l-ol

[0041] 3. 3-methyloct-4-enal

[0042] 4. 3-methyloct-5-enal

[0043] 5. 3,7-dimethyloct-4-en-l-ol

[0044] 6. 3,7-dimethyloct-5-en-l-ol

[0045] 7. 3,7-dimethyloct-4-enal

[0046] 8. 3,7-dimethyloct-5-enal

[0047] 9. 3-methylnon-4-en-l-ol

[0048] 10. 3-methylnon-5-en-l-ol

[0049] 11. 3-methylnon-4-enal

[0050] 12. 3-methylnon-5-enal

[0051] 13. 3-methyldec-4-en-l-ol

[0052] 14. 3-methyldec-5-en-l-ol

[0053] 15. 3-methyldec-4-enal

[0054] 16. 3-methyldec-5-enal 17. 3-methylundec-4-en-l-ol

[0055] 18. 3-methylundec-5-en-l-ol

[0056] 19. 3-methylundec-4-enal

[0057] 20. 3-methylundec-5-enal

[0058] 21. 3-methyldodec-4-en-l-ol

[0059] 22. 3-methyldodec-5-en-l-ol

[0060] 23. 3-methyldodec-4-enal

[0061] 24. 3-methyldodec-5-enal

[0062] 25. 3-methyltridec-4-en-l-ol

[0063] 26. 3-methyltridec-5-en-l-ol

[0064] 27. 3-methyltridec-4-enal

[0065] 28. 3-methyltridec-5-enal

[0066] 29. 3 -methyltridecanal

[0067] 30. 3-methyltetradec-4-en-l-ol

[0068] 31. 3 -methyltetradec-5 -en- 1 -ol

[0069] 32. 3-methyltetradec-4-enal

[0070] 33. 3 -methyltetradec-5 -enal

[0071] 34. 3 -methyltetradecanal

[0072] 35. 3,6-dimethylhept-4-en-l-ol

[0073] 36. 3,6-dimethylhept-5-en-l-ol

[0074] 37. 3,6-dimethylhept-4-enal

[0075] 38. 3,6-dimethylhept-5-enal

[0076] 39. 3,6,7-trimethyloct-5-en-l-ol

[0077] 40. 3,6,7-trimethyloct-4-en-l-ol

[0078] 41. 3,6,7-trimethyloct-5-enal

[0079] 42. 3,6,7-trimethyloct-4-enal

[0080] 43. 3,6-dimethyloct-5-en-l-ol

[0081] 44. 3,6-dimethyloct-4-en-l-ol

[0082] 45. 3,6-dimethyloct-5-enal

[0083] 46. 3,6-dimethyloct-4-enal

[0084] 47. 3,6-dimethylnon-5-en-l-ol

[0085] 48. 3,6-dimethylnon-4-en-l-ol

[0086] 49. 3,6-dimethylnon-5-enal

[0087] 50. 3,6-dimethylnon-4-enal 51. 3,6-dimethylnonan-l-ol

[0088] 52. 3,6-dimethylnonanal

[0089] 53. 3,6-dimethyldec-5-en-l-ol

[0090] 54. 3,6-dimethyldec-4-en-l-ol

[0091] 55. 3,6-dimethyldec-5-enal

[0092] 56. 3,6-dimethyldec-4-enal

[0093] 57. 3,6-dimethyldecan-l-ol

[0094] 58. 3,6-dimethyldecanal

[0095] 59. 3,6-dimethylundec-5-en-l-ol

[0096] 60. 3,6-dimethylundec-4-en-l-ol

[0097] 61. 3,6-dimethylundec-5-enal

[0098] 62. 3,6-dimethylundec-4-enal

[0099] 63. 3,6-dimethylundecan-l-ol

[0100] 64. 3,6-dimethylundecanal

[0101] 65. 3,6-dimethyldodec-5-en-l-ol

[0102] 66. 3,6-dimethyldodec-4-en-l-ol

[0103] 67. 3,6-dimethyldodec-5-enal

[0104] 68. 3,6-dimethyldodec-4-enal

[0105] 69. 3,6-dimethyldodecan-l-ol

[0106] 70. 3,6-dimethyldodecanal

[0107] 71. 3,6-dimethyltridec-5-en-l-ol

[0108] 72. 3,6-dimethyltridec-4-en-l-ol

[0109] 73. 3,6-dimethyltridec-5-enal

[0110] 74. 3,6-dimethyltridec-4-enal

[0111] 75. 3,6-dimethyltridecan-l-ol

[0112] 76. 3,6-dimethyltridecanal

[0113] 77. 3,6-dimethyltetradec-5-en-l-ol

[0114] 78. 3.6-dimethyltetradec-4-en- 1 -ol

[0115] 79. 3,6-dimethyltetradec-5-enal

[0116] 80. 3,6-dimethyltetradec-4-enal

[0117] 81. 3.6-dimethyltetradecan- 1 -ol

[0118] 82. 3,6-dimethyltetradecanal

[0119] 83. 3-methylhept-4-en-l-ol

[0120] 84. 3-methylhept-5-en-l-ol 85. 3-methylhept-5-enal

[0121] 86. 3-methylhept-4-enal

[0122] In an embodiment of the present invention, mixture of odorous compounds of formula (I) is / are selected from any of the following mixtures:

[0123] The present invention also relates to fragrance, flavor and / or deodorizing / masking compositions comprising any of the above defined mixtures of compounds of formula (I).

[0124] The compounds of formula (I) may be used alone, as mixtures thereof, or in combination with a base material.

[0125] As used herein, the "base material" includes all known fragrance / flavor materials selected from the extensive range of natural products like: essential oils, extracts, resinoids or isolates and synthetic materials currently available, such as: hydrocarbons, alcohols, aldehydes and ketones, ethers and acetals, esters and lactones, nitriles, oximes or heterocycles, and / or in admixture with one or more ingredients or excipients / adjuvants conventionally used in conjunction with odorants in fragrance and / or flavor compositions, for example: solvents / diluents, stabilizers, carrier materials, and other auxiliary agents commonly used in the art.

[0126] The compounds of formula (I) may be used in a broad range of fragrance applications, e.g., in any field of fine and functional perfumery, such as perfumes, air care products, household products, laundry products, body care products and cosmetics. The compounds can be employed in widely varying amounts, depending upon the specific application and on the nature and quantity of other odorant ingredients. According to a preferred embodiment of the invention, the fragrance, flavor and / or deodorizing / masking composition contains at least one compound according to formula (I) as previously described, in quantities between 0.00001 and 99.9 wt. %, for example between 0.0001 and 95 wt. %, for example between 0.001 and 25 wt. %, preferably between 0.01 and 15 wt. %, more advantageously between 0.1 and 10 wt. %, in particular between 1 and 5 wt. %, in each case relative to the entire composition.

[0127] According to a particularly preferred embodiment of the invention, in addition to a compound of formula (I) according to the present invention, the fragrance, flavor and / or deodorizing / masking composition according to the present invention contains additional odorants, for example in a quantity of 0.1 to 99.9 wt. %, preferably 5-90 wt. %, in particular 15-70 wt. %, relative to the entire fragrance and / or flavor composition.

[0128] The compounds of formula (I) as described herein above may be employed in a consumer product base simply by directly mixing at least one compound of formula (I), or a fragrance composition comprising said compound or compounds of formula (I) with the consumer product base; or they may, in an earlier step, be entrapped with an entrapment material, for example, polymers, capsules, microcapsules and / or nanocapsules, liposomes, film formers, absorbents such as active carbon or zeolites, cyclic oligosaccharides, cyclic glycolurils, and mixtures of two or more thereof, or they may be chemically bonded to substrates, which are adapted to release the fragrance molecule upon application of an external stimulus such as light, enzyme, air, water or the like, and then mixed with the consumer product base.

[0129] Thus, the invention can be useful for existing methods of manufacturing a fragrance, flavor and / or deodorizing / masking composition, comprising the incorporation of one or more compounds of formula (I) as a fragrance, flavor and / or deodorizing / masking ingredient, either by directly admixing the compound to the consumer product base or by admixing a fragrance, flavor and / or deodorizing / masking composition comprising said one or more compounds of formula (I), which may then be mixed with a consumer product base, using conventional techniques and methods. Through the addition of an olfactory-acceptable amount of at least one compound of formula (I) of the present invention as hereinabove described, the odor notes of a consumer product base can be improved, enhanced, and / or modified. In an embodiment according to the present invention, the fragrance, flavor and / or deodorizing / masking composition comprises a compound of formula (I) that is selected from any of the compounds and / or from a mixture of two or more of the said compounds given above, in particular from any one or a mixture of two or more of the said compounds cited above.

[0130] In an embodiment of the present invention, the claimed fragrance, flavor and / or deodorizing / masking composition is advantageously used as a perfumery composition. Perfumery compositions according to the present invention generally include a perfume, a cologne, an eau du toilette, and / or an eau de parfum. In an embodiment of the present invention, the claimed fragrance, flavor and / or deodorizing / masking composition is advantageously used in a cosmetic formulation, a personal care product, a cleansing product, a fabric softener, and / or air freshener, and the like. Furthermore, it is within the purview of embodiments of the invention that the novel fragrance, flavor and / or deodorizing / masking composition(s) and / or novel compound(s) of formula (I) described herein may be integrated into building materials, wall and floor coverings, vehicle components, and the like.

[0131] The compounds of formula (I) can combine with numerous known natural or synthetic fragrance, flavor and / or deodorizing / masking materials, whereby the range of the natural ingredients can embrace not only readily-volatile but also semi-volatile and slightly-volatile components and the range of the synthetic ingredients can embrace representatives from many classes of substances, such as described in Steffen Arctander, Perfume and Flavor Chemicals, vol.l&2, Montclair, N.J., 1969; Steffen Arctander, Perfume and Flavor Materials of Natural Origin, Elizabeth, N.J., 1960 or Horst Surburg, Johannes Panten, Common Fragrance and Flavor Materials, Wiley -VCH, Weinheim, 2016 and as will be evident from the following nonlimitting compilation:

[0132] Natural products such as:

[0133] Ajowan oil, Amyris oil, Armoise oil, Artemisia oil, Basil oil, Bees wax absolute, Bergamot oil, Birch tar oil, Black pepper oil, Black pepper oleoresin, Camphor oil, Cananga oil, Caraway oil, Cardamom oil, Carrot seed oil, Castoreum absolute, Cedar leaf oil, Cedarwood oil, Celery seed oil, Chamomile oil, Cinnamon bark oil, Cinnamon leaf oil, Cistus absolute, Cistus oil, Citronella oil, Citronella terpenes, Clary sage oil, Clove oil rectified, Cognac oil white, Coriander seed oil, Cumin seed oil, Cypress oil, Davana oil, Dill seed oil, Elemi oil, Elemi resinoid, Eucalyptus oil, Fir needle oil, Galbanum oil, Geranium oil, Ginger oil Indian, Grapefruit oil, Guaiacwood oil, Gurjun balsam, Jasmin absolute, Jatamansi oil, Juniper berry oil, Juniper leaf oil, Kachur oil, Labdanum absolute, Labdanum resinoid, Lavender oil, Lemon oil, Lemon oil terpenes, Lemongrass oil, Lime oil, Litsea cubeba oil, Litsea cubeba terpenes, Lobhan choya resinoid, Mandarin oil, Mentha arvensis oil, Mentha citrata oil, Mimosa absolute, Myrrh resinoid, Nagarmotha oil, Nutmeg oil, Oakmoss absolute, Oakmoss resinoid, Olibanum oil, Olibanum resinoid, Orange oil, Origanum oil, Palma rosa oil, Patchouli oil, Peppermint oil, Peru Balsam resinoid, Petitgrain oil, Pine needle oil, Pink pepper oil, Rose absolute, Rose oil, Rosemary oil, Sandalwood oil, Seaweed absolute, Spearmint oil, Sugandh kokila oil, Sugandh mantri oil, Tagete oil, Tolu Balsam resinoid, Tuberose absolute, Turmeric oil, Turpentine oil, Valerian oil, Vetiver oil, Vetiver terpenes.

[0134] Synthetic raw materials for instance:

[0135] Esters such as: Aldehyde Cl 6, Allyl amyl glycolate, Allyl caproate, Allyl cyclohexyl propionate, Allyl heptoate, Allyl phenoxy acetate, Amyl acetate iso, Amyl benzoate, Amyl butyrate, Amyl caproate, Amyl cinnamate, Amyl isovalerate, Amyl phenyl acetate, Amyl propionate, Amyl salicylate iso, Amyris acetate, Anisyl acetate, Benzyl acetate, Benzyl benzoate, Benzyl butyrate, Benzyl cinnamate, Benzyl formate, Benzyl isobutyrate, Benzyl isoeugenol, Benzyl propionate, Benzyl salicylate, Benzyl tiglate, Butyl acetate, Butyl butyrate, Butyl butyryl lactate, Caryophyllene acetate, Cedryl acetate, Cinnamyl acetate, Cinnamyl butyrate, Cis-3-hexenyl acetate, Cis-3-hexenyl benzoate, Cis-3-hexenyl caproate, Cis-3- hexenyl formate, Cis-3-hexenyl isobutyrate, Cis-3 -hexenyl -2 -methyl butyrate, Cis-3-hexenyl propionate, Cis-3-hexenyl salicylate, Cis-3-hexenyl tiglate, Citronellyl acetate, Citronellyl butyrate, Citronellyl formate, Citronellyl isobutyrate, Citronellyl propionate, Citronellyl tiglate, Cyclabute, Cyclogalbanate, Cyclohexyl ethyl acetate, Decyl acetate, Dibutyl phthalate, Diethyl malonate, Diethyl phthalate, Dihydromyrcenyl acetate, Dimethyl octanyl acetate, Dimethyl phenyl ethyl carbinyl acetate, Dioctyl adipate, Dioctyl phthalate, Dimethyl benzyl carbinyl acetate, Dimethyl benzyl carbinyl butyrate, Ethyl linalyl acetate, Ethyl 2-methyl butyrate, Ethyl 3 -phenyl propionate, Ethyl acetate, Ethyl acetoacetate, Ethyl benzoate, Ethyl butyrate, Ethyl caprate, Ethyl caproate, Ethyl caprylate, Ethyl cinnamate, Ethyl heptoate, Ethyl hexyl acetate, Ethyl isobutyrate, Ethyl laurate, Ethyl pelargonate, Ethyl phenoxy acetate, Ethyl phenyl acetate, Ethyl phenyl glycidate, Ethyl propionate, Ethyl safranate, Ethyl salicylate, Ethyl valerate, Eugenyl acetate, Evernyl, Fenchyl acetate, Floramat, Frescolat ML, Fructone, Fruitate, Geranyl acetate, Geranyl butyrate, Geranyl formate, Geranyl propionate, Geranyl tiglate, Givescone, Guaiol acetate, Hedionate, Hedione, Helvetolide, Herbanate, Hexyl acetate, Hexyl benzoate, n-Hexyl butyrate, Hexyl caproate, Hexyl isobutyrate, Hexyl propionate, Hexyl salicylate, Isobornyl acetate, Isobutyl acetate, Isobutyl phenyl acetate, Isobutyl salicylate, Isoeugenyl acetate, Isononyl acetate, Isopentyrate, Isopropyl 2-methyl butyrate, Isopropyl myristate, Jasmonyl, Liffarome, Linalyl acetate, Mahagonate, Manzanate, Menthanyl acetate, Menthyl acetate, Methyl benzoate, 2-Methyl butyl acetate, Methyl camomille, Methyl cinnamate, Methyl cyclogeranate, Methyl heptine carbonate, Methyl laurate, Methyl octine carbonate, Methyl phenyl acetate, Methyl salicylate, Methyl-2 -methyl butyrate, Neofolione, Nopyl acetate, Octenyl acetate, Octyl acetate, Octyl isobutyrate, Para cresyl acetate, Para cresyl isobutyrate, Para cresyl phenyl acetate, Pear ester, Peranat, Phenoxy ethyl isobutyrate, Phenyl ethyl acetate, Phenyl ethyl butyrate, Phenyl ethyl formate, Phenyl ethyl isobutyrate, Phenyl ethyl phenyl acetate, Phenyl ethyl propionate, Phenyl ethyl salicylate, Phenyl ethyl tiglate, Phenyl propyl isobutyrate, Prenyl acetate, Romandolide, Sagecete, Styrallyl acetate, Styrallyl propionate, Tangerinol, Terpinyl acetate, Thesaron, Trans-2 -hexenyl acetate, Tropicate, Verdox, Verdyl acetate, Verdyl propionate, Vertenex, Vetikol acetate, Vetiveryl acetate, Yasmolys.

[0136] Lactones such as: Ambrettolide, Arova N, Celeriax, Decalactone delta, Decalactone gamma, Dodecalactone delta, Dodecalactone gamma, Ethylene brassylate, Exaltolide, Heptalactone gamma, Hexalactone delta, Hexalactone gamma, Methyl laitone, Methyl octalactone, Nonalactone delta, Nonalactone gamma, Octahydrocoumarine, Octalactone delta, Octalactone gamma, Rootylone, Silvanone supra, Undecalactone delta, Undecalactone gamma, Valerolactone gamma, 10-OxaHexaDecanolide (OHD musk), Coumarin, Habanolide, Jasmolactone.

[0137] Aldehydes such as: Acetaldehyde, Adoxal, Aldehyde CIO, Aldehyde Cl l iso, Aldehyde Cl l moa, Aldehyde Cl l undecylenic, Aldehyde Cl l undecylic, Aldehyde C12 lauric, Aldehyde C12 MNA, Anisaldehyde, Amyl cinnamaldehyde, Benzaldehyde, Bourgeonal, Campholenaldehyde, Cantonal, Cetonal, Cinnamic aldehyde, Cis-4-decenal, Cis-6-nonenal, Citral, Citronellal, Citronellyl oxyacetaldehyde, Cocal, Cuminaldehyde, Curgix, Cyclal C, Cyclamen aldehyde, Cyclomyral, Cyclovertal, Decenal 9, Dupical, Empetal, Ethyl vanillin, Floralozone, Florhydral, Geraldehyde, Helional®, Heliotropin, Heptanal, Hexanal, Hexyl cinnamaldehyde, Hivernal® neo, Hydratropaldehyde, Hydroxycitronellal, Intreleven aldehyde, Isobutavan, Isocyclocitral, Isovaleraldehyde, Lilial, Limonenal, Maceal, Mefranal, Melonal, Methyl cinnamaldehyde, Nonadien-al trans-2 cis-6, Nonanal, Octanal, Oncidal, Para tolyl aldehyde, Phenyl acetaldehyde, Phenyl propyl aldehyde, Precyclemone B, Safranal, Salicylaldehyde, Scentenal, Syringa aldehyde, Trans-4-decenal, Trans-2-dodecenal, Trans-2- hexenal, Trans-2 -nonenal, Trifernal, Vanillin, Veratraldehyde, Vernaldehyde

[0138] Ketones such as: Acetanisol, Acetoin, Acetophenone, Aldron, Allyl ionone, Benzophenone, Benzyl acetone, Calone, Camphor, Carvone d-, Carvone 1-, Cashmeran, Cedryl methyl ketone, Cepionate, Claritone, Cosmone, Crysolide, Cyclotene, Damascenone, Damascene alpha, Damascene beta, Damascene delta, Damascene gamma, Diacetyl, Dihydro beta ionone, Dihydro isojasmonate, Dimethyl octenone, Dynascone, Ethyl amyl ketone, Ethyl maltol, Fenchone, Filbertone, Geranyl acetone, Globanone, Heptyl cyclopentanone, Ionone alpha, Ionone beta, Ionone pure, Iriswood, Irone alpha, Iso E Super, Isofenchone, Isojasmone T, Isolene K, Isomenthone, Isophorone, Jasmone cis-, Kambemoir, Kephalis, Koavone, Lavendinal, Maltol, Menthone, Methyl acetophenone, Methyl amyl ketone, Methyl heptenone, Methyl hexyl ketone, Methyl ionone gamma, Methyl naphthyl ketone beta, Methyl nonyl ketone, Muscenone, Muscone, Nectaryl, Orinox, OTBC Ketone, Para tertbutylcyclohexanone, Patchwood, Phantolid, Pharaone, Piperitone, Plicatone, Raspberry ketone, Raspberry ketone methyl ether, Safraleine, Spirogalbanone pure, Tonalid, Trimofix O, Veloutone, Vetikon.

[0139] Alcohols such as: Alcohol oxo C13, Amber core, Ambermax, Ambrinol, Amyl vinyl carbinol, Anisic alcohol, Bacdanol, Benzyl alcohol, Butanol, Cedrol crystals, Cinnamic alcohol, Citronellol, Coranol, Decanol, Dimethyl benzyl carbinol, Dimethyl octanol, Dimethyl phenyl ethyl carbinol, Dimetol, Fenchol, Hexanol, Isobomeol, Isobornyl cyclohexanol, Javanol, Keflorol, Kohinool, Lauryl alcohol, Lilyflore, Linalool oxide, Mayol, Menthol, Norlimbanol, Octanol, Osyrol, Para tertbutylcyclohexanol, Phenoxanol, Phenoxyethanol, Phenyl ethyl alcohol, Phenyl propyl alcohol, Propylene glycol, Rosaphen, Rose glycol, Styrallyl alcohol, Tricyclodecane dimethanol, Tetrahydro linalool, Tetrahydro myrcenol, Timberol, Undecavertol, Cis-3-hexenol, Citronellol laevo, Cyclofloranol, Dihydrolinalool, Dihydromyrcenol, Dimyrcetol, Ebanol, Geraniol, Isopulegol, Linalool, Nerol, Nerolidol, Nonadien-ol trans-2 cis-6, Polysantol, Rosalva, Sandalmysore core, Sandalore, Terpinen-4-ol, Terpineol, Trans-2 -hexenol Phenols such as: Butylated hydroxyanisole, Dihydroeugenol, Dimethyl hydroquinone, Dimethyl resorcinol, Eugenol pure, Guaiacol, Isoeugenol, Meta cresol, Methyl diantilis, Para cresol, Propenyl guaethol, Thymol, Ultravanil.

[0140] Ethers such as: Ambroxan, Anethole, Anther, Benzyl isoamyl ether, Benzyl isopropyl ether, Benzyl isovalerate, Boisiris, Cedramber, Cetalox, Decyl methyl ether, Dibenzyl ether, Dihydro rose oxide, Diphenyl oxide, Doremox, Estragole, Ethyl linalool, Eucalyptol, Galaxolide, Gyrane, Herbavert, Lime oxide, Madrox, Methyl isoeugenol, Naphthyl isobutyl ether beta, Nerol oxide, Nerolin bromelia, Para cresyl butyl ether, Para cresyl methyl ether, Petiole, Phenyl ethyl methyl ether, Rhubafuran, Rose oxide, Rosyrane, Trisamber, Vetylbois K, Yara yara

[0141] Acetals such as: Acetal CD, Acetal R, Amberketal, Boisambrene forte, Citrathal, 1,1- Diethoxyethane, Emeraldine, Freshopal, Herboxane, Indoflor, Jacinthaflor, Magnolan, Spirambrene, Viridine, Elintaal, Glycolierral, Karanal, Methyl pamplemousse,

[0142] Hydrocarbons such as: Bisabolene, Camphene, Carene delta 3, Caryophyllene, Cedrene, Cymene para, Dipentene, Diphenyl methane, Isolongifolene, Limonene d-, Longifolene, Myrcene, Naphthalene, Ocimene, Pinene alpha, Pinene beta, Styrene, Terpinene gamma, Terpinolene, 1,3,5-Undecatriene, Verdoracine.

[0143] Sulphur compounds such as: Corps cassis, Dibutyl sulphide, Dimethyl sulphide, Exovert, Grapefruit thiol, Oxane, Ribes mercaptan, Sulfurol, Thiocineol.

[0144] Nitriles such as: Cinnamyl nitrile, Citronellyl nitrile, Citronitrile, Clonal, Cumin nitrile, Hexyl cyclopentanone, Irisnitrile, Lemonile, Peonile, Tridecyl nitrile, Agrumen nitrile, n-decyl nitrile.

[0145] Oximes such as: Buccoxime, Labienoxime, Stemone.

[0146] Nitrogen heterocycles such as: 2-acetylpyrazine, 2-acetylpyridine, sec-butylquinoline, Corps racine, 2-ethyl-3,5(or 6)-dimethylpyrazine, Furfuryl pyrrole, Indole, Isobutyl quinoline, 2- Isobutyl-3(or 6)-m ethoxypyrazine, Isopropyl quinoline, Maritima, p-m ethyl quinoline, Skatol, 2,3,5-trimethylpyrazine.

[0147] Nitro compound such as: Musk Ketone. Schiff bases such as: Aurantiol, Helianthral, Ligantraal, Verdantiol.

[0148] Other materials such as: Acetanilide, Gardamide, Paradisamide, Dimethyl anthranilate, Methyl anthranilate, n-Butyric acid, Capric acid, Caproic acid, Caprylic acid, Phenylacetic acid, Caryophyllene oxide, Cedroxyde, Tobacarol.

[0149] The compounds of formula (I) can accordingly advantageously be used for the production of fragrance, flavor and / or deodorizing / masking compositions also comprising, as will be evident from the foregoing compilation, a wide range of known odorants / fragrance, flavor and / or deodorizing / masking materials. In the production of such compositions, the known fragrance, flavor and / or deodorizing / masking materials referred to earlier can be used according to methods that are known to the perfumer such as, for example, according to W. A. Poucher, Perfumes, Cosmetics and Soaps 2, 7th Edition, Chapman and Hall, London 1974.

[0150] In an embodiment of the present invention, the claimed fragrance, flavor and / or deodorizing / masking composition comprises in addition to the compound(s) of formula (I), at least one ester and / or one alcohol (other than compound (I), if present), preferably at least a mixture of ester and alcohol; the said ester and / or alcohol are preferably selected from the list defined herein above. In an embodiment of the present invention, the claimed odorant composition is characterised by a total content of the compound(s) of formula (I) together with the ester(s) and / or alcohol(s) which is superior to 25 wt.%, preferably superior to 50 wt.%, for example superior to 75 wt.%, or even superior to 90 wt.%.

[0151] The preparation process of compounds of formula (I)

[0152] A = -CH2OAC, -CH2OH, -CHO dotted line represents a double or single bond

[0153] R-i is an alkyl or alkylidene group according to the present invention comprises the steps of a. Reacting an aldehyde of formula (II), for example wherein R2 is an alkyl group or an alkenyl group, for example an alkyl group having 2, 3, 4, 5, 6, 7, 8 or 9 carbon atoms or an alkenyl group having 2, 3, 4, 5, 6, 7, 8 or 9 carbon atoms,

[0154] II with an alcohol of formula

[0155] Isoprenol to get a compound of formula (III) b. Reacting the compound of formula (III) with Ra-Ni and hydrogen to get a compound of formula (IV) c. Reacting the compound of formula (IV) with acetic anhydride to get a compound of formula (V) which is the compound of formula (I) wherein A represents -CH2OAC d. Optionally and additionally reacting the compound of formula (V) with sodium hydroxide and / or potassium hydroxide in water to get a compound of formula (VI) which is the compound of formula (I) wherein A represents -CH2OH e. optionally and additionally oxidating the compound of formula (VI) employing (2, 2,6,6- Tetramethylpiperidin-l-yl)oxyl (TEMPO) or 4-hydroxy-TEMPO along with N- chlorosuccinimide to obtain a compound of formula (VII) which is the compound of formula (I) wherein A represents -CHO wherein Ri is selected from alkyl or alkylidene groups having up to 9 carbon atoms with a linear or branched chain.

[0156] Ri can advantageously be selected from methyl, ethyl, w-propyl, isopropyl, / / -butyl, isobutyl, w-pentyl, w-hexyl, n-heptyl, n-octyl, n-nonyl, methylidene, ethylidene, propylidene, isopropylidene, butylidene, isobutylidene, pentylidene, hexylidene, heptylidene, octylidene, or nonylidene.

[0157] In an embodiment, step a is performed in presence of an acid catalyst, for example para-toluene sulfonic acid.

[0158] In an embodiment, step b is performed at a temperature between 90-140 °C.

[0159] In an embodiment, step c is performed in presence of an acid catalyst, for example para-toluene sulfonic acid.

[0160] In an embodiment, sodium hydroxide in water is used in step d.

[0161] Compounds of formulae (V), (VI) and (VII) can be represented by compounds of formula (I) respectively with A representing -CIEOAc, -CH2OH, and -CHO.

[0162] In an embodiment, compound of formula (VI) can be hydrogenated using Ra-Ni catalyst, for example at a temperature between 90-140 °C, to get a compound of formula (VIII).

[0163] In an embodiment, TEMPO-mediated oxidation of compounds of formula (VIII) can afford compounds of formula (IX)

[0164] In an embodiment, there is provided a process for the preparation of a mixture of trans / cis compounds of formula (I) consisting of the following two compounds wherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain, e.g. an alkyl group with C2 to C9 atoms.

[0165] In an embodiment, there is provided a process for the preparation of a mixture of trans / cis compounds of formula (I) consisting of the following two compounds wherein A = -CH2OAC, -CH2OH or -CHO and R3 and R4 are selected from H and alkyl groups with a linear or branched chain such that the sum of carbon atoms in R3 and R4 is from 2 carbon atoms to up to 8 carbon atoms.

[0166] In an embodiment, there is provided a process for the preparation of a mixture of trans / cis compounds of formula (I) consisting of the following four compounds trans cis wherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain, e.g. an alkyl group with C2 to C9 atoms and R3 and R4 are selected from H and alkyl groups with a linear or branched chain such that the sum of carbon atoms in R3 and R4 is from 2 carbon atoms to up to 8 carbon atoms.

[0167] Following scheme illustrates an embodiment of the synthetic process in detail. Raney Ni, H2°

[0168] The following mixtures of compounds were advantageously synthesized by employing the process disclosed in this invention

[0169]

[0170] It should be noted that the above compounds are advantageously obtained as a mixture of their stereoisomers as well as regioisomers.

[0171] For example, the second entry in the above table is obtained as the following mixture.

[0172] In addition to the above alcohols and aldehydes, corresponding acetates (of general formula V) were synthesized as a mixture of their stereoisomers and regioisomers; and were also advantageously evaluated for their organoleptic properties.

[0173] PREPARATION

[0174] The compounds of formula (I) may refer to both stereoisomeric and / or regioisomeric mixture or individually isolated isomer which are prepared in 5 steps. WO2012025934A1 discloses five step process using cyclic ketone as a starting material whereas the present invention discloses process from aldehyde.

[0175] Aliphatic aldehydes reacted with isoprenol using para-toluene sulfonic acid ( TSA) as a catalyst in the first step involving Prins reaction which gave compound of formula (III). Compounds of formula (III) were hydrogenated to give compounds of formula (IV). Pyran ring opening of compunds of formula (IV) using acetic anhydride and catalytic TSA afforded compounds (V). Hydrolysis of acetate of compounds (V) gave alcohols of formula (VI).

[0176] With a goal to substantially improve the oxidation protocol, use of various secondary oxidants was explored and it was found that N-chlorosuccinimide (NCS) worked very well with catalytic TEMPO or 4-O-allyl TEMPO as a primary oxidant, when used in a buffered solution of NaHCOa and K2CO3 in water with / / -tetrabutylammonium chloride as a phase transfer catalyst, with DCE (di chloroethane) as the organic solvent. Instead of / / -tetrabutylammonium chloride (TBAC1), one can also effectively use / / -tetrabutylammonium bromide (TBAB) as a phase transfer catalyst.

[0177] Here we have demonstrated efficient process for oxidation of primary alcohol to aldehyde using catalytic amount (0.1 eq) of TEMPO and N-Chlorosuccinimide as co-oxidant in aqueous medium in short reaction time 1-2 h.

[0178] Alternatively, 4-hydroxy-TEMPO or 4-O-allyl TEMPO can also be used in 0.2 to 0.3 equivalents. Although equivalents of 4-hydroxy-TEMPO used are higher than those of TEMPO, the advantage of using 4-hydroxy-TEMPO is due to absence of a colored impurity. In many cases, a colored impurity resulting from use of TEMPO cannot be separated from desired aldehyde product in distillation as the colored impurity and the aldehyde have similar boiling points as well as similar retention times on gas chromatography analysis. When 4- hydroxy-TEMPO is used, there is no colored impurity and hence purity of aldehyde products can be improved. and characterization data of some selected are given below.

[0179] Example-1:

[0180] Synthesis of a mixture of 3-methyloct-4-enal (compound 3) and 3-methyloct-5-enal (compound 4) using w-butyraldehyde and isoprenol

[0181] Step-1: Synthesis of a mixture of 4-methyl-6-propyl-3,6-dihydro-2H-pyran, 4-methyl-2- propyl-3,6-dihy dr o-2H- pyran and 4-methylene-2-propyltetrahydro-2H- pyran :

[0182] To a solution of ^-butyraldehyde (300.0 g, 4.16 mol) in methylcyclohexane (900 mL) with Dean-Stark condenser were added / ?TSA (11.9 g, 0.062 mol) and 3-methyl-3-buten-l-ol (430.0 g, 4.99 mol) at room temperature. Then reaction mixture was heated at 130 °C for 15 h. The reaction mixture was cooled at room temperature and quenched with water (500 mL). Aqueous layer was separated and organic layer was washed with 5% aqueous sodium bicarbonate solution (2 x 250 mL) followed by brine (2 x 300 mL) and water (300 mL). The organic layer was dried over sodium sulfate and filtered. Solvents were evaporated on rota-evaporator to afford crude material (612 g) which was further purified by fractional distillation to afford desired product (356.0 g, 60%) as a colorless liquid.

[0183] IR (Neat): 2959.4, 2874.2, 1680.8, 1449.8, 1380.2 cm’1

[0184] 1HNMR (400 MHz, CDCh): 8 5.40- 5.31 (m, 2 H), 4.11 - 3.95 (m, 3 H), 3.63 - 3.42 (m, 2 H), 2.23 - 2.16 (m, 1 H), 1.96 - 1.73 (m, 2 H), 1.68 - 1.36 (m, 3 H), 0.94 - 0.90 (m, 3 H).

[0185] GC-MS (m / z): 140.1 (M+), 97.1

[0186] Step-2: Synthesis of 4-methyl-2-propyltetrahydro-2H-pyran:

[0187] To a solution of a mixture from step-1 (345.0 g, 2.46 mol) in 2-propanol (150 mL) in an autoclave was added Raney nickel (20.0 g). The reaction mixture was heated at 100 °C under 200 psi pressure of hydrogen and maintained for 16 h. The reaction mixture was cooled to 30 °C and filtered through a bed of hyflow. The hyflow bed was washed with 2-propanol (2 x 100 mL). The organic layer was concentrated to afford 310.0 g (88% yield) of desired product. IR (Neat): 2955.9, 2924.6, 2871.6, 1457.6 cm’1

[0188] ’H NMR (400 MHz, CDCh): 6 3.98 - 3.19 (m, 3 H), 1.66 - 1.20 (m, 9 H), 0.92 - 0.88 (m, 6 H). GC-MS (m / z): 142.1 (M+), 123.1, 99.1

[0189] Step-3: Synthesis of a mixture of 3-methyloct-4-en-l-yl acetate and 3-methyloct-5-en-l- yl acetate:

[0190] A solution of 4-methyl-2-propyltetrahydro-2H-pyran (200.0 g, 1.40 mol), 4- methylbenzenesulfonic acid hydrate (13.4 g, 0.07 mol) and acetic anhydride (187.0 g, 1.82 mol) was heated at 115-120 °C for 20 h. After completion of reaction, excess acetic anhydride was removed by vacuum distillation. The reaction mixture was cooled to room temperature and quenched with water (500 ml) and extracted with ethyl acetate (2 x 200 mL). Combined organic layer was washed with sodium bicarbonate (2 x 200 mL), followed by brine (2 x 100 mL) and dried over sodium sulphate. The organic layer concentrated using rota evaporator to afford a crude mass (230 g) which was purified by fractional distillation under reduced pressure to obtain a regioisomeric mixture of acetates in (132 g, 50% yield) as colorless liquid.

[0191] IR (Neat): 2960.8, 2930.1, 1740.4 cm’1

[0192] ‘HNMR (400 MHz, CDCh): 8 5.47 -5.19 (m, 2 H), 4.12 - 3.98 (m, 2 H), 2.03 - 1.32 (m, 10 H), 0.99 - 0.85 (m, 6 H).

[0193] GC-MS (m / z): 184.2 (M+)

[0194] Step-4: Synthesis of a mixture of 3-methyloct-4-en-l-ol (compound 1) and 3-methyloct- 5-en-l-ol (compound 2):

[0195] To a mixture of acetates from step-3 (130.0 g, 0.70 mol) was added a solution of potassium hydroxide (79.0 g, 1.4 mol) in water (66.0 mL) and methanol (65 ml) over 10 min at 25 °C. The reaction mixture was heated at 110 °C for 5 h and then cooled to 25 °C. Reaction mixture was cooled at room temperature and methanol was evaporated using rota-evaporator. The residue was neutralized with 10% hydrochloric acid (50 mL). Organic layer was separated and washed with water (2 x 100 mL) and saturated brine (2 x 100 mL). The resulting crude was distilled to afford desired alcohol as a mixture of regioisomers (91.0 g, 91% yield) in the form of a yellowish oil.

[0196] Odor profile: aldehydic, floral, watery, green

[0197] IR (Neat): 3323.4, 2959.5, 2873.1, 1457.3 cm’1

[0198] ‘HNMR (400 MHz, CDCh): 6 5.44 - 5.24 (m, 2 H), 3.69 - 3.63 (m, 2 H), 2.05 - 1.33 (m, 9 H), 1.00 - 0.86 (m, 6 H).

[0199] GC-MS (m / z): 142.1 (M+), 124.1, 109.1, 95.1

[0200] Step-5: Synthesis of a mixture of 3-methyloct-4-enal (compound 3) and 3-methyloct-5- enal (compound 4): To a solution of a mixture of octenyl alcohols from step-4 (20.0 g, 0.14 mol) in 1,2- di chloroethane (120 mL) at room temperature were sequentially added tetra-w-butyl ammonium chloride hydrate (16.6 g, 0.28 mol) and TEMPO (2.19 g, 0.014 mol). To this reaction mixture was then added a buffer solution of sodium hydrogen carbonate (9.92 g, 0.11 mol) and potassium carbonate (1.63 g, 0.011 mol) in water (150 mL). The reaction mixture was stirred at room temperature for 10 min. Then 7V-chlorosuccinimide (24.4 g, 0.18 mol) was added in portions over 10 minutes. The reaction mixture was stirred at room temperature for 2 h and then it was quenched with saturated solution of sodium bicarbonate. The organic layer was separated and washed with water and brine. The organic layer was dried over sodium sulphate and concentrated under reduced pressure to afford crude aldehyde. Crude product was purified by column chromatography using 100-200 silica gel and using 1-2% of ethyl acetate / n-hexane as an eleunt. Further distillation afforded the desired octenyl aldehyde as a regioisomeric mixture (5.4 g, 27% yield) as colorless liquid.

[0201] Odor profile: Strong aldehydic, floral, green.

[0202] IR (Neat): 2961.4, 2931.0, 2875.2, 1724.3 cm’11H NMR (400 MHz, CDCh): 8 9.75 -9.69 (m, 1 H), 5.50 - 5.38 (m, 2 H), 2.75 - 1.92 (m, 6 H), 1.38 - 1.32 (m, 1 H), 1.06 - 0.84 (m, 6 H).

[0203] GC-MS (m / z): 140.1 (M+), 125.1, 111.1, 97.1.

[0204] Example-2

[0205] Synthesis of a mixture of 3,7-dimethyloct-4-enal (compound 7) and 3,7-dimethyloct-5- enal (compound 8) using isovaleraldehyde and isoprenol

[0206] Step-1: Synthesis of a mixture of 2-isobutyl-4-methylenetetrahydro-2H-pyran, 6- isobutyl-4-methyl-3,6-dihydro-2H-pyran and 2-isobutyl-4-methyl-3,6-dihydro-2H- pyran:

[0207] This compound was synthesized from isovaleraldehyde and isoprenol using the method described in step-1 in example- 1 :

[0208] IR (Neat): 2956.6, 2916.5, 1680.9, 1668.6 cm’1

[0209] ‘H NMR (400 MHz, CDCh): 8 5.39- 5.30 (m, 2 H), 4.12 - 3.94 (m, 3 H), 3.63 - 3.32 (m, 2 H), 2.20 - 1.68 (m, 4 H), 1.54 - 1.17 (m, 2 H), 0.91 - 0.87 (m, 6 H).

[0210] GC-MS (m / z): 154.1 (M+), 139.1, 97.1

[0211] Step-2: Synthesis of 2-isobutyl-4-methyltetrahydro-2H-pyran: This compound was synthesized from the mixture of products obtained in step-1, example 2 using the method described in step-2 in example-1 :

[0212] IR (Neat): 2953.8, 2922.8, 1457.7 cm’1

[0213] 1H NMR (400 MHz, CDCh): 8 3.97 - 3.24 (m, 3 H), 1.78 - 1.11 (m, 8 H), 0.91 - 0.86 (m, 9 H).

[0214] GC-MS (m / z): 156.1 (M+), 99.1.

[0215] Step-3: Synthesis of a mixture of 3,7-dimethyloct-4-en-l-yl acetate and 3,7-dimethyloct-

[0216] 5-en-l-yl acetate:

[0217] This compound was synthesized from the mixture obtained in step-2 example 2 using the method described in step-3 in example-1:

[0218] IR (Neat): 2958.0, 1740.6, 1230.7 cm’1

[0219] ‘H NMR (400 MHz, CDCh): 6 5.40 -5.10 (m, 2 H), 4.14 - 3.96 (m, 2 H), 2.29 - 2.18 (m, 1 H), 2.04 - 1.83 (m, 5 H), 1.64 - 1.55 (m, 3 H), 1.00 - 0.85 (m, 9 H).

[0220] Step-4: Synthesis of a mixture 3,7-dimethyloct-4-en-l-ol (compound 5) and 3,7- dimethyloct-5-en-l-ol (compound 6):

[0221] This compound was synthesized from the mixture obtained in step-3, example 2, using the procedure of step-4 as given in example-1 :

[0222] Odor profile: Citrus, Aldehydic, floral, geranium and lemon

[0223] IR (Neat): 3325.9, 2956.4, 1665.9, 1460.6 cm’1

[0224] ’H NMR (400 MHz, CDCh): 6 5.42 - 5.17 (m, 2 H), 3.70 - 3.61 (m, 2 H), 2.05 - 1.83 (m, 2 H), 1.63 - 1.51 (m, 4 H), 1.37 - 1.18 (m, 1 H), 1.00 - 0.85 (m, 9 H).

[0225] GC-MS (m / z): 156.1 (M+), 138.1, 123.1, 109.1, 95.1

[0226] Step-5: Synthesis of a mixture of 3,7-dimethyloct-4-enal (compound 7), and 3,7- dimethyloct-5-enal (compound 8):

[0227] This compound was synthesized from product of step-4 example 2 by using the method described in step-5 in example- 1 :

[0228] Odor profile: Aldehydic, metallic, green, floral and woody.

[0229] IR (Neat): 2957.9, 2872.5, 1724.8, 1461.9 cm’1

[0230] XH NMR (400 MHz, CDCh): 6 9.78 -9.72 (m, 1 H), 5.45 - 5.22 (m, 2 H), 2.75 - 2.70 (m, 1 H),

[0231] 2.46 - 2.00 (m, 3 H), 1.98 -1.86 (m, 2 H), 1.63 - 1.58 (m, 1 H), 1.09 - 0.86 (m, 8 H).

[0232] GC-MS (m / z): 154.1 (M+), 139.1, 121.1, 111.1, 98.1. Example-3:

[0233] Synthesis of a mixture of 3-methylnon-4-enal (compound 11) and 3-methylnon-5-enal (compound 12) using n-pentanal and isoprenol

[0234] Step-1: Synthesis of a mixture of 6-butyl-4-methyl-3,6-dihydro-2H-pyran, 2-butyl-4- methyl-3,6-dihydro-2H-pyran and 2-butyl-4-methylenetetrahydro-2H-pyran:

[0235] This compound was synthesized from w-pentanal and isoprenol using the method described in step-1 in example- 1 :

[0236] IR (Neat): 2930.0, 2859.7, 1730.7, 1681.0 cm’1

[0237] ‘H NMR (400 MHz, CDCh): 8 5.40- 5.32 (m, 2 H), 4.17 - 3.95 (m, 2 H), 3.64 - 3.40 (m, 2 H), 2.24 - 1.30 (m, 9 H), 0.92 - 0.88 (m, 3 H).

[0238] GC-MS (m / z): 154.1 (M+), 97.1

[0239] Step-2: Synthesis of 2-butyl-4-methyltetrahydro-2H-pyran:

[0240] This compound was synthesized from the mixture of products obtained in step-1, example 3 using the method described in step-2 in example-1 :

[0241] IR (Neat): 2953.7, 2925.6, 2838.3, 1457.5 cm’1

[0242] 1H NMR (400 MHz, CDCh): 6 3.99 - 3.18 (m, 3 H), 1.60 - 1.16 (m, 9 H), 0.92 - 0.85 (m, 6 H).

[0243] GC-MS (m / z): 154.1 (M+), 97.1

[0244] Step-3: Synthesis of a mixture of 3-methylnon-4-en-l-yl acetate and 3-methylnon-5-en- 1-yl acetate:

[0245] This compound was synthesized from the mixture obtained in step-2 example 3 using the method described in step-3 in example-1:

[0246] IR (Neat): 2959.9, 2929.7, 2873.8, 1740.1, 1458.9 cm’1

[0247] ‘HNMR (400 MHz, CDCh): 6 5.41 - 5.18 (m, 2 H), 4.11 - 4.00 (m, 2 H), 2.05 - 1.27 (m, 12 H), 0.99 - 0.85 (m, 6 H).

[0248] Step-4: Synthesis of a mixture of 3-methylnon-4-en-l-ol (compound 9) and 3- methylnon-5-en-l-ol (compound 10):

[0249] This compound was synthesized from the mixture obtained in step-3, example 3, using the procedure of step-4 as given in example-1 :

[0250] Odor profile: aldehydic, floral

[0251] IR (Neat): 3336.0, 2957.9, 2872.5, 1457.5 cm’1

[0252] ‘H NMR (400 MHz, CDCh): 6 5.44 - 5.23 (m, 2 H), 3.68 - 3.62 (m, 2 H), 2.25 - 1.29 (m, 9 H), 0.99 - 0. 85 (m, 6 H). GC-MS (m / z): 156.2 (M+), 138.1, 123.1, 109.1, 95.1, 81.1

[0253] Step-5: Synthesis of a mixture of 3-methylnon-4-enal (compound 11) and 3-methylnon- 5-enal (compound 12):

[0254] This compound was synthesized from product of step-4 example 3 by using the method described in step-5 in example- 1 :

[0255] Odor profile: aldehydic, watery, floral, green

[0256] IR (Neat): 2959.5, 2928.5, 2874.4, 1724.8 cm’1

[0257] ’H NMR (400 MHz, CDCh): 8 9.75 - 9.68 (m, 1 H), 5.47 - 5.30 (m, 2 H), 2.42 - 1.94 (m, 5 H), 1.39 - 1.24 (m, 4 H), 1.05 - 0.85 (m, 6 H).

[0258] GC-MS (m / z): 154.1 (M+), 139.1, 125.1, 111.1, 97.0.

[0259] Example-4:

[0260] Synthesis of a mixture of 3-methyldec-4-enal (compound 15) and 3-methyldec-5-enal (compound 16) using n-hexanal and isoprenol

[0261] Step-1: Synthesis of a mixture of 4-methylene-2-pentyltetrahydro-2H-pyran 4-methyl-6- pentyl-3,6-dihydro-2H-pyran and 4-methyl-2-pentyl-3,6-dihydro-2H-pyran:

[0262] To a solution of / / -hexanal (200.0 g, 1.99 mol) in methylcyclohexane (200 mL) with Dean- Stark condenser was added / ?TSA (7.7 g, 0.03 mol) and 3-methyl-3-buten-l-ol (206.0 g, 2.40 mol) at room temperature. Then reaction mixture was heated at 130°C for 18 h. The reaction mixture was cooled at room temperature and quenched with water (500 mL). Aqueous layer was separated and organic layer was washed with 5% aqueous sodium bicarbonate solution (2 x 200 mL) followed by brine (2 x 200 mL) and water (100 mL). The organic layer was dried over sodium sulphate and filtered. Solvents were evaporated on rota-evaporator to afford crude material which was further purified by fractional distillation to afford desired product (286.0 g, 90%) as a colourless liquid.

[0263] IR (Neat): 2928.4, 2857.6, 1731.8, 1680.6 cm’1

[0264] XH NMR (400 MHz, CDCh): 6 5.39-5.31 (m, 2 H), 4.17 - 4.08 (m, 1 H), 3.99 - 3.95 (m, 1 H), 3.63 - 3.57 (m, 1 H), 3.46 - 3.40 (m, 1 H), 2.24 - 2.18 (m, 1 H), 1.96 - 1.74 (m, 2 H), 1.74 (m, 2 H), 1.55 - 1. 28 (m, 6 H), 0.90 - 0.86 (m, 3 H).

[0265] GC-MS (m / z): 168.2 (M+), 153.1, 139.1, 124.1, 97.1

[0266] Step-2: Synthesis of 4-methyl-2-pentyltetrahydro-2H- pyran: To a solution of a product of step-1 (160.0 g , 0.95 mol) in 2-propanol (90 mL) in an autoclave was added Raney nickel (8.0 g, 0.09 mol). The reaction mixture was heated at 100 °C under 200 psi pressure of hydrogen and maintained for 11 h. The reaction mixture was cooled to 30 °C and filtered through a bed of hyflow. The hyflow bed was washed with 2-propanol (2 x 20 mL). The organic layer was concentrated to afford 157.0 g (82% yield) of desired product.

[0267] IR (Neat): 2925.9, 2859.1, 1457.9 cm’1

[0268] ‘HNMR (400 MHz, CDCh): 8 3.99 - 3.20 (m, 3 H), 1.66 - 1.18 (m, 13 H), 0.92 - 0.88 (m, 6 H).

[0269] GC-MS (m / z): 170.2 (M+), 99.1.

[0270] Step-3: Synthesis of a mixture of 3-methyldec-4-en-l-yl acetate and 3-methyldec-5-en-l- yl acetate:

[0271] A solution of 4-methyl-2-pentyltetrahydro-2H-pyran (150.0 g, 0.88 mol), 4- methylbenzenesulfonic acid hydrate (8.4 g, 0.044 mol) and acetic anhydride (116.0 g, 1.14 mol) was heated at 130 °C for 65 h. The reaction mixture was cooled to room temperature and quenched with water (500 ml) and extracted with ethyl acetate (2 x 250 mL). Combined organic layer was washed with sodium bicarbonate (2 x 250 mL), followed by brine (2 x 100 mL) and dried over sodium sulfate. The organic layer concentrated using rota evaporator to afford a crude mass (213 g) which was purified by fractional distillation under reduced pressure to obtain a regioisomeric mixture of acetates 71.7 g, 38% yield.

[0272] IR (Neat): 2958.6, 2926.7, 2859.7, 1741.4, 1231.0 cm’1

[0273] ‘HNMR (400 MHz, CDCh): 6 5.42 - 5.20 (m, 2 H), 4.12 - 3.98 (m, 2 H), 2.22 - 1.27 (m, 14 H), 0.99 -0.85 (m, 6 H).

[0274] Step-4: Synthesis of a mixture 3-methyldec-4-en-l-ol (compound 13) and 3-methyldec-5- en-l-ol (compound 14):

[0275] To a mixture of acetates from step-3 (70.0 g, 0.32 mol) was added a solution of potassium hydroxide (37.0 g, 0.65 mol) in water (50.0 mL) and methanol (50 ml) over 10 min at 25 °C. The reaction mixture was heated at 100 °C for 5 h and then cooled to 25 °C. Reaction mixture was cooled at room temperature and methanol was evaporated using rota-evaporator. The residue was neutralized with 10% hydrochloric acid (50 mL). Organic layer was separated and washed with water (2 x 80 mL) and saturated brine (2 x 80 mL). The resulting crude was distilled to afford desired alcohol as a mixture of regioisomers (53.0 g, 96% yield) as a yellowish oil.

[0276] Odor profile: floral, aldehydic, watery IR (Neat): 3323.2, 2957.5, 2925.0, 2858.9, 1457.8 cm’1

[0277] ‘HNMR (400 MHz, CDCh): 6 5.44 - 5.11 (m, 2 H), 3.69 - 3.58 (m, 2 H), 2.00 - 1.23 (m, 11 H), 0.98 - 0.95 (m, 6 H).

[0278] GC-MS (m / z): 170.2 (M+)

[0279] Step-5: Synthesis of a mixture of 3-methyldec-4-enal (compound 15) and 3-methyldec-5- enal (compound 16):

[0280] To a solution of a mixture of alcohols from step-4 (40.0 g, 0.23 mol) in 1,2-di chloroethane (240 mL) at room temperature were sequentially added tetra-w-butylammonium chloride hydrate (27.8 g, 0.047 mol) and 4-O-allyl TEMPO (5.3 g, 0.023 mol). To this reaction mixture was then added a buffer solution of sodium hydrogen carbonate (16.6 g, 0.197 mol) and potassium carbonate (2.7 g, 0.019 mol) in water (300 mL). The reaction mixture was stirred at room temperature for 10 min. Then 7V-chlorosuccinimide (40.8 g, 0.30 mol) was added in portions over 10 minutes. The reaction mixture was stirred at room temperature for 3 h and then it was quenched with saturated solution of sodium bicarbonate. The organic layer was separated and washed with water and brine. The organic layer was dried over sodium sulphate and concentrated under reduced pressure to afford crude aldehyde. Fractional distillation under reduced pressure afforded the desired aldehyde as a regioisomeric mixture (25.7 g, 63% yield) as a colourless liquid.

[0281] Odor profile: aldehydic, floral, watery green

[0282] IR (Neat): 2958.7, 2926.9, 2858.2, 1725.3 cm’1

[0283] 'H NMR (400 MHz, CDCh): 8 9.75 - 9.68 (m, 1 H), 5.47 - 5.29 (m, 2 H), 2.45 - 1.94 (m, 5 H), 1.35 - 1.24 (m, 6 H), 1.05 - 0.85 (m, 6 H).

[0284] GC-MS (m / z): 168.1 (M+), 153.1, 139.1, 124.1, 97.1

[0285] Example-5:

[0286] Synthesis of a mixture of 3-methylundec-4-enal (compound 19) and 3-methylundec-5-enal (compound 20) using n-heptanal and isoprenol:

[0287] Step-1: Synthesis of a mixture of 6-hexyl-4-methyl-3,6-dihydro-2H-pyran, 2-hexyl-4- methyl-3,6-dihydro-2H-pyran and 4-methylene-2-pentyltetrahydro-2H-pyran :

[0288] This compound was synthesized from ^-heptanal and isoprenol using the method described in step-1 in example- 1 : IR (Neat): 2926.8, 2855.8,1680.9 cm’1

[0289] ‘H NMR (400 MHz, CDCh): 6 5.39- 5.32 (m, 2 H), 4.13 - 3.95 (m, 2 H), 3.63 - 3.42 (m, 1 H), 2.23 - 1.2 8 (m, 14 H), 0.88 - 0.85 (m, 3 H).

[0290] GC-MS (m / z): 182.2 (M+), 97.0

[0291] Step-2: Synthesis of 2-hexyl-4-methyltetrahydro-2H-pyran:

[0292] This compound was synthesized from the mixture of products obtained in step-1, example 5 using the method described in step-2 in example-1 :

[0293] IR (Neat): 2924.1, 2855.8,1457.9 cm’1

[0294] ‘HNMR (400 MHz, CDCh): 8 3.99 - 3.17 (m, 3 H), 2.02 - 1.17 (m, 15 H), 1.04 - 0.85 (m 6 H).

[0295] GC-MS (m / z): 182.2 (M+), 99.0

[0296] Step-3: Synthesis of a mixture of 3-methylundec-4-en-l-yl acetate and 3-methylundec-5- en-l-yl acetate:

[0297] This compound was synthesized from the mixture of products obtained in step-2, example 5 using the method described in step-3 in example-1 :

[0298] IR (Neat): 2958.1, 2926.1, 2857.0, 1741.4 cm’1

[0299] ‘HNMR (400 MHz, CDCh): 6 5.42 - 5.30 (m, 2 H), 4.10 - 4.02 (m, 2 H), 2.02 - 1.24 (m, 16 H), 0.98 - 0.87 (m, 6 H).

[0300] GC-MS (m / z): 227.2 (M+), 166.1, 138.1, 124.1, 109.1, 95.1, 81.0.

[0301] Step-4: Synthesis of a mixture of 3-methylundec-4-en-l-ol (compound 17) and 3- methylundec-5-en-l-ol (compound 18):

[0302] This compound was synthesized from the mixture of products obtained in step-3, example 5 using the method described in step-4 in example-1 :

[0303] Odor profile: Mild floral, aldehydic

[0304] IR (Neat): 3322.1, 2924.4, 2856.6, 1457.9 cm’1

[0305] ‘HNMR (400 MHz, CDCh): 6 5.44 - 5.23 (m, 2 H), 3.71 - 3.61 (m, 2 H), 2.23 - 1.26 (m, 14 H), 0.99 - 0.85 (m, 6 H).

[0306] GC-MS (m / z): 184.2 (M+), 166.2, 140.1, 123.1, 109.1, 95.1, 81.1. Step-5: Synthesis of a mixture of 3-methylundec-4-enal (compound 19) and 3- methylundec-5-enal (compound 20):

[0307] This compound was synthesized from the mixture of products obtained in step-4, example 5 using the method described in step-5 in example-1 :

[0308] Odor profile: Aldehydic, floral, green, watery

[0309] IR (Neat): 2958.3, 2925.9, 2856.4, 1725.6 cm’1

[0310] ’H NMR (400 MHz, CDCh): 8 9.75 - 9.69 (m, 1 H), 5.47 - 5.31 (m, 2 H), 2.44 - 1.95 (m, 7

[0311] H), 1.40 - 1.22 (m, 6 H), 1.05 - 0.86 (m, 6 H).

[0312] GC-MS (m / z): 182.2 (M+), 167.1, 153.2, 138.1, 125.1, 111.1, 97.0.

[0313] Example-6:

[0314] Synthesis of a mixture of 3-methyldodec-4-enal (compound 23) and 3-methyldodec-5-enal

[0315] (compound 24) using n-octanal and isoprenol

[0316] Step-1: Synthesis of a mixture of 6-heptyl-4-methyl-3,6-dihydro-2H-pyran, 2-heptyl-4- methyl-3,6-dihydro-2H-pyran and 2-heptyl-4-methylenetetrahydro-2H-pyran:

[0317] This compound was synthesized from / / -octanal and isoprenol using the method described in step-1 in example- 1 :

[0318] IR (Neat): 2925.5, 2854.9,1731.3 cm’1

[0319] XH NMR (400 MHz, CDCh): 6 5.39- 5.31 (m, 1 H), 4.13 - 3.95 (m, 2 H), 3.63 - 3.40 (m, 1 H),

[0320] 2.38 - 1.27 (m, 17 H), 0.92 - 0.85 (m, 3 H).

[0321] GC-MS (m / z): 196.2 (M+), 97.1

[0322] Step-2: Synthesis of a mixture of 2-heptyl-4-methyltetrahydro-2H-pyran:

[0323] This compound was synthesized from the mixture of products obtained in step-1, example 6 using the method described in step-2 in example-1 :

[0324] IR (Neat): 2923.5, 2854.8,1457.9 cm’1

[0325] ‘HNMR (400 MHz, CDCh): 5 3.99 - 3.17 (m, 3 H), 2.00 - 1.15 (m, 15 H), 0.92 - 0.85 (m, 6 H).

[0326] GC-MS (m / z): 198.2 (M+), 99.1

[0327] Step-3: Synthesis of a mixture of 3-methyldodec-4-en-l-yl acetate and 3-methyldodec-5- en-l-yl acetate:

[0328] This compound was synthesized from the mixture of products obtained in step-2, example 6 using the method described in step-3 in example-1 : IR (Neat): 2958.1, 2925.7, 2856.2,1741.6 cm’1

[0329] ‘HNMR (400 MHz, CDCh): 6 5.40 - 5.17 (m, 2 H), 4.11 - 4.00 (m, 2 H), 2.02 - 1.50 (m, 18 H), 0.98 - 0.84 (m, 6 H).

[0330] GC-MS (m / z): 241.0 (M+), 225.1, 180.2.

[0331] Step-4: Synthesis of a mixture of 3-methyldodec-4-en-l-ol (compound 21) and 3- methyldodec-5-en-l-ol (compound 22):

[0332] This compound was synthesized from the mixture of products obtained in step-3, example 6 using the method described in step-4 in example-1 :

[0333] Odor profile: Mild floral, aldehydic.

[0334] IR (Neat): 3325.7, 2957.1, 2923.8, 2855.4,1458.2 cm’1

[0335] ‘HNMR (400 MHz, CDCh): 8 5.44 - 5.23 (m, 2 H), 3.71 - 3.59 (m, 2 H), 2.03 - 1.25 (m, 16 H), 0.99 - 0.85 (m, 6 H).

[0336] GC-MS (m / z): 198.2 (M+), 180.2, 152.2, 125.1, 109.1, 81.1

[0337] Step-5: Synthesis of a mixture of 3-methyldodec-4-enal (compound 23) and 3- methyldodec-5-enal (compound 24):

[0338] This compound was synthesized from the mixture of products obtained in step-4, example 6 using the method described in step-5 in example-1 :

[0339] Odor profile: aldehydic, floral, green, watery

[0340] IR (Neat): 2958.1, 2925.3, 2855.7,1726.2 cm’1

[0341] ‘H NMR (400 MHz, CDCh): 6 9.75 - 9.69 (m, 1 H), 5.45 - 5.30 (m, 2 H), 2.41 - 1.93 (m, 5 H), 1.33 - 1.25 (m, 10 H), 1.05 - 0.85 (m, 6 H).

[0342] GC-MS (m / z): 196.2 (M+), 181.2, 167.2, 152.2, 125.1, 111.1, 97.1

[0343] Example-7:

[0344] Synthesis of a mixture of 3-methyltridec-4-enal (compound 27) and 3-methyltridec-5-enal

[0345] (compound 28) using n-nonanal and isoprenol

[0346] Step-1: Synthesis of a mixture of 4-methyl-6-octyl-3,6-dihydro-2H-pyran, 4-methyl-2- octyl-3,6-dihy dr o-2H- pyran and 4-methylene-2-octyltetrahydro-2H- pyran :

[0347] This compound was synthesized from / / -nonanal and isoprenol using the method described in step-1 in example- 1 :

[0348] IR (Neat): 2924.1, 2854.7,1730.1, 1680.9 cm’1 ‘H NMR (400 MHz, CDCh): 6 5.39- 5.32 (m, 2 H), 4.13 - 3.95 (m, 2 H), 3.63 - 3.33 (m, 3 H), 2.24 - 1.22 (m, 16 H), 0.88 - 0.85 (m, 3 H).

[0349] GC-MS (m / z): 210.2 (M+), 97.1

[0350] Step-2: Synthesis of 4-methyl-2-octyltetrahydro-2H- pyran:

[0351] This compound was synthesized from the mixture of products obtained in step-1, example 7 using the method described in step-2 in example-1 :

[0352] IR (Neat): 2921.1, 2854.0, 1458.1 cm’1

[0353] ‘HNMR (400 MHz, CDCh): 8 3.99 - 3.17 (m, 3 H), 2.02 - 1.26 (m, H 19), 1.04 - 0.88 (m, 6 H).

[0354] GC-MS (m / z): 211.2 (M+), 99.1

[0355] Step-3: Synthesis of a mixture of 3-methyltridec-4-en-l-yl acetate and 3-methyltridec-5- en-l-yl acetate:

[0356] This compound was synthesized from the mixture of products obtained in step-2, example 7 using the method described in step-3 in example-1 :

[0357] IR (Neat): 2957.8, 2924.9, 2855.5, 1742.0 cm’1

[0358] ‘H NMR (400 MHz, CDCh): 6 5.43 - 5.29 (m, 2 H), 4.12 -4.01 (m, 2 H), 2.03 - 1.25 (m, 20 H), 0.99 -0. 85 (m, 6 H).

[0359] GC-MS (m / z): 255.4 (M+), 194.2, 165.2, 137.1, 109.1, 81.1

[0360] Step-4: Synthesis of a mixture of 3-methyltridec-4-en-l-ol (compound 25) and 3- methyltridec-5-en-l-ol (compound 26):

[0361] This compound was synthesized from the mixture of products obtained in step-3, example 7 using the method described in step-4 in example-1 :

[0362] IR (Neat): 3332.7, 2923.4, 2854.9,1458.3 cm’1

[0363] ‘HNMR (400 MHz, CDCh): 6 5.43 - 5.23 (m, 2 H), 3.70 - 3.61 (m, 2 H), 2.22 - 1.29 (m, 17 H), 0.99 - 0.85 (m, 6 H).

[0364] GC-MS (m / z): 212.2 (M+), 194.2, 168.2, 137.1, 109.1, 81.1

[0365] Odor profile: aldehydic, floral

[0366] Step-5: Synthesis of a mixture of 3-methyltridec-4-enal (compound 27) and 3- methyltridec-5-enal (compound 28): This compound was synthesized from the mixture of products obtained in step-4, example 7 using the method described in step-5 in example-1 :

[0367] IR (Neat): 2924.6, 2855.0,1326.3 cm’1

[0368] ‘H NMR (400 MHz, CDCh): 8 9.75 - 9.69 (m, 1 H), 5.47 - 5.29 (m, 2 H), 2.44 - 1.95 (m, 6 H), 1.31 - 1.15 (m, 11 H), 1.05 - 0.85 (m, 6 H).

[0369] GC-MS (m / z): 210.2 (M+), 195.2, 181.2, 166.2, 111.1, 97.1

[0370] Odor profile: aldehydic, floral, watery

[0371] Example-8:

[0372] Synthesis of a mixture of 3-methyltetradec-4-enal (compound 32) and 3-methyltetradec-5- enal(compound 33) using n-decanal and isoprenol:

[0373] Step-1: Synthesis of a mixture of 4-methyl-6-nonyl-3,6-dihydro-2H-pyran, 4-methyl-2- nonyl-3,6-dihydro-2H-pyran and 4-methylene-2-nonyltetrahydro-2H-pyran:

[0374] This compound was synthesized from / / -decanal and isoprenol using the method described in step-1 in example- 1 :

[0375] IR (Neat): 2923.5, 2853.9, 1680.8 cm’1

[0376] ‘H NMR (400 MHz, CDCh): 6 5.39- 5.32 (m, 2 H), 4.13 - 3.95 (m, 2 H), 3.63 - 3.41 (m, 1 H), 2.20 - 1.42 (m, 8 H), 1.38 - 1.89 (m, 12 H), 0.87 (t, J= 6.0 Hz, 3H).

[0377] GC-MS (m / z): 224.2 (M+), 206.2, 180.2, 155.1, 97.1

[0378] Step-2: Synthesis of 4-methyl-2-nonyltetrahydro-2H-pyran:

[0379] This compound was synthesized from the mixture of products obtained in step-1, example 8 using the method described in step-2 in example-1 :

[0380] IR (Neat): 2923.0, 2854.1, 1458.3 cm’1

[0381] ‘HNMR (400 MHz, CDCh): 5 4.13 - 4.03 (m, 3 H), 2.30 - 2.26 (m, 1 H), 1.66 - 1.00 (m, 20

[0382] H), 0.99 - 0. 83 (m, 6 H).

[0383] GC-MS (m / z): 227.1 (M+H), 209.2

[0384] Step-3: Synthesis of a mixture of 3-methyltetradec-4-en-l-yl acetate and 3- methyltetradec-5-en-l-yl acetate:

[0385] This compound was synthesized from the mixture of products obtained in step-2, example 8 using the method described in step-3 in example-1 :

[0386] IR (Neat): 2924.5, 2855.1, 1742.1 cm’1XH NMR (400 MHz, CDCh): 6 5.43 - 5.18 (m, 2 H), 3.72 - 3.59 (m, 2 H), 2.03 - 1.41 (m, 12

[0387] H), 1.39 - 1.20 (m, 10 H), 0.99 - 0.85 (m, 6 H).

[0388] GC-MS (m / z): 268.2 (M+), 180.2, 138.1, 109.1, 81.1

[0389] Step-4: Synthesis of a mixture of 3-methyltetradec-4-en-l-ol (compound 30) and 3- methyltetradec-5-en-l-ol (compound 31):

[0390] This compound was synthesized from the mixture of products obtained in step-3, example 8 using the method described in step-4 in example-1 :

[0391] Odor profile: Mild aldehydic floral

[0392] IR (Neat): 3325.6, 2923.2, 2854.4,1458.5 cm’1

[0393] ‘HNMR (400 MHz, CDCh): 8 5.44 - 5.23 (m, 2 H), 3.72 - 3.59 (m, 2 H), 2.30 - 1.54 (m, 8

[0394] H), 1.30 - 1.25 (m, 12 H), 0.99 - 0.85 (m, 6 H).

[0395] GC-MS (m / z): 226.4 (M+), 208.2, 182.2, 138.1, 109.1, 81.1

[0396] Step-5: Synthesis of a mixture of 3-methyltetradec-4-enal (compound 32) and 3- methyltetradec-5-enal (compound 33):

[0397] This compound was synthesized from the mixture of products obtained in step-4, example 8 using the method described in step-5 in example-1 :

[0398] Odor profile: Floral, rosy

[0399] IR (Neat): 2924.2, 2854.6, 1726.6, 1459.4 cm’1

[0400] ’H NMR (400 MHz, CDCh): 6 9.75 - 9.69 (m, 1 H), 5.47 - 5.29 (m, 2 H), 2.40 - 1.95 (m, 7

[0401] H), 1.38 - 1.15 (m, 12 H), 1.05 - 0.85 (m, 6 H).

[0402] GC-MS (m / z): 224.2 (M+), 206.2, 180.2

[0403] Example-9

[0404] Synthesis of a mixture of 3,6-dimethylhept-4-enal (compound 37) and 3,6-dimethylhept- 5-enal (compound 38) using isobutyraldehyde and isoprenol

[0405] Step-1: Synthesis of a mixture of 6-isopropyl-4-methyl-3,6-dihydro-2H-pyran, 2- isopropyl-4-methyl-3,6-dihydro-2H-pyran and 2-isopropyl-4-methylenetetrahydro-2H- pyran:

[0406] This compound was synthesized from isobutyraldehyde and isoprenol using the method described in step-1 in example-1 :

[0407] IR (Neat): 2960.5, 2847.5, 1652.7, 1468.8 cm’1 ’H NMR (400 MHz, CDCh): 6 5.40- 4.71 (m, 2 H), 4.20 - 3.31 (m, 3 H), 3.16 - 2.96 (m, 1 H), 2.31 - 1.69 (m, 4 H), 0.94 - 0.90 (m, 6 H).

[0408] GC-MS (m / z): 140.1 (M+), 115.1, 97.1.

[0409] Step-2: Synthesis of 2-isopropyl-4-methyltetrahydro-2H- pyran:

[0410] This compound was synthesized from the mixture of products obtained in step-1, example 9 using the method described in step-2 in example-1 :

[0411] IR (Neat): 2955.2, 2927.5, 2873.5, 1458.7 cm’1

[0412] ’H NMR (400 MHz, CDCh): 8 4.00 - 3.34 (m, 3 H), 1.68 - 1.17 (m, 6 H), 0.93 - 0.83 (m, 9 H).

[0413] GC-MS (m / z): 143.1 (M+), 125.2, 99.1

[0414] Step-3: Synthesis of a mixture of 3,6-dimethylhept-4-en-l-yl acetate and 2,5-dimethyl-7- (prop-l-en-2-yloxy)hept-2-ene:

[0415] This compound was synthesized from the mixture obtained in step-2 example 9 using the method described in step-3 in example-1:

[0416] IR (Neat): 2960.4, 2871.5, 1740.1 cm’1

[0417] 'H NMR (400 MHz, CDCh): 6 5.36 - 4.91 (m, 2 H), 4.10 - 3.94 (m, 2 H), 2.59 - 2.16 (m, 1 H), 2.02 (s, 3 H), 1.68 - 1.39 (m, 3 H), 0.98 - 0.87 (m, 9 H).

[0418] GC-MS (m / z): 185.2 (M+), 169.1, 151.1, 123.1, 111.1.

[0419] Step-4: Synthesis of a mixture of 3,6-dimethylhept-4-en-l-ol (compound 35) and 3,6- dimethylhept-5-en-l-ol (compound 36):

[0420] This compound was synthesized from the mixture obtained in step-3, example 9, using the procedure of step-4 as given in example-1 :

[0421] Odor profile: white floral, watery, muguet

[0422] IR (Neat): 3326.5, 2958.4, 2927.9, 2870.4, 1458.4 cm’1

[0423] ’H NMR (400 MHz, CDCh): 6 5.40 - 4.97 (m, 2 H), 3.68 - 3.57 (m, 2 H), 2.61 - 2,16 (m, 2 H), 1.96 - 1.42 (m, 2 H), 0.98 - 0.86 (m, 9 H).

[0424] GC-MS (m / z): 142.1 (M+), 124.1, 109.1, 96.0

[0425] Step-5: Synthesis of a mixture of 3,6-dimethylhept-4-enal (compound 37) and 3,6- dimethylhept-5-enal (compound 38):

[0426] This compound was synthesized from product of step-4 example 9 by using the method described in step-5 in example- 1 :

[0427] Odor profile: white floral, Kflorol-like, muguet, watery

[0428] IR (Neat): 2960.4, 2871.9, 1725.1 cm’1 ’H NMR (400 MHz, CDCh): 6 9.70 -9.69 (m, 1 H), 5.43 - 5.01 (m, 2 H), 2.71 - 2.21 (m, 4 H), 1.038 (t, J= 6.8 Hz, 3 H), 0.96 - 0.92 (m, 6 H).

[0429] GC-MS (m / z): 140.1 (M+), 125.1, 109.1, 96.1.

[0430] Example-10:

[0431] Synthesis of a mixture of 3,6-dimethylundec-5-enal (compound 61) and 3,6- dimethylundec-4-enal (compound 62) using 2-methyleneheptanal and isoprenol

[0432] Step-1: Synthesis of a 2-methyleneheptanal:

[0433] To a solution of ^-heptanal (100 g, 876 mmol) was added formaldehyde (85 g, 1051 mmol), acetic acid (5.01 ml, 88 mmol) and dibutylamine (5.66 g, 43.8 mmol). The resulting mixture was heated to 60 °C and stirred for 16 h. After the GC confirmation of the complete consumption of the starting material, reaction mixture was cooled to 25 °C.

[0434] The two phase mixture was separated and the organic phase was further diluted with diethyl ether. The organic phase was washed with dil HC1 (1 x 300 mL), followed by washing with saturated aq. NaHCCh (1 x 500 mL), water (1 x 50 mL) and brine (1 x 400 mL). The organic phase was then dried over Na2SO4, filtered and concentrated in vacuo. 110 g crude material was obtained. Flash distillation was done to afford desired product (48.0 g, 43%) as a colorless liquid.

[0435] IR (Neat): 2929.6, 2861.2, 1691.1, 1627.8 cm’1

[0436] ’H NMR (400 MHz, CDCh): 8 9.51 (s, 1 H), 6.22 (s, 1 H), 5.96 (s, 1 H), 2.23 - 2.19 (t, J= 7.2 Hz, 2 H), 1.46 - 1.39 (m, 2 H), 1.32- 1.23 (m, 4 H), 0.87 (t, J= 6.8 Hz, 3 H).

[0437] GC-MS (m / z): 126.1 (M+).

[0438] Step-2: Synthesis of a mixture of 2-(hept-l-en-2-yl)-4-methylenetetrahydro-2H-pyran , 6- (hept-l-en-2-yl)-4-methyl-3,6-dihydro-2H-pyran, and 2-(hept-l-en-2-yl)-4-methyl-3,6- dihydr o-2H-pyran :

[0439] To a solution of 2-methyleneheptanal (500 g, 3962 mmol)) in methylcycohexane (1250 mL) with Dean-Stark condenser was added / ?TSA (11.30 g, 59.4 mmol) and 3-methyl-3-buten-l-ol (482 ml, 4754 mmol) at room temperature. Then reaction mixture was heated at 130°C for 18 h. The reaction mixture was cooled at room temperature and quenched with water (700 mL). Aqueous layer was separated and organic layer was washed with 5% aqueous sodium bicarbonate solution (2 x 700 mL) followed by brine (2 x 700 mL) and water (700 mL). The organic layer was dried overe sodium sulfate and filtered. Solvents were evaporated on rota- evaporator to afford crude material which was further purified by fractional distillation to afford desired product (250.0 g, 33%) as a light yellow liquid.

[0440] IR (Neat): 2928.4, 2857.6, 1731.8, 1680.6 cm’1

[0441] 1H NMR (400 MHz, CDCh): 8 5.39 - 4.71 (m, 2 H), 4.17 - 3.35 (m, 3 H), 2.14 - 1.87 (m, 3 H), 1.73 - 1.59 (m, 5 H), 1.44 - 1.23 (m, 6 H), 0.88 - 0.84 (m, 3 H).

[0442] GC-MS (m / z): 194.2 (M+), 164.2, 123.1

[0443] Step-3: Synthesis of 2-(heptan-2-yl)-4-methyltetrahydro-2H-pyran:

[0444] To a solution of a product of step-2, (250 g, 1287 mmol) in 2-propanol (250 mL) in an autoclave was added Raney nickel (15.0 g, 0.09 mmol). The reaction mixture was heated at 110 °C under 15 kg pressure of hydrogen and maintained for 16 h. The reaction mixture was cooled to 30 °C and filtered through a bed of hyflow. The hyflow bed was washed with 2-propanol (2 x 100 mL). The organic layer was concentrated to afford 220.0 g (86% yield) of desired product.

[0445] IR (Neat): 2925.52, 2955.43, 2857.34, 1458.26 cm’1

[0446] ’H NMR (400 MHz, CDCh): 6 4.07 - 3.94 (m, 1 H), 3.80 - 3.61 (m, 1 H), 3.38 - 3.26 (m, 1 H), 1.53 - 1.46 (m, 4 H), 1.36 - 1.17 (m, 8 H), 1.04 - 1.01 (m, 2 H), 0.91 - 0.80 (m, 9 H).

[0447] GC-MS (m / z): 198.2 (M).

[0448] Step-4: Synthesis of a mixture of 3,6-dimethylundec-5-en-l-yl acetate and 3,6- dimethylundec-4-en-l-yl acetate:

[0449] A mixture of product of step-3 (150.0 g, 756 mmol), acetic anhydride (103 g, 1512 mmol) and / ?TSA (28.7 g, 151 mmol) was heated to 150 °C for 40 h. The reaction mixture was cooled to room temperature and quenched with water (500 ml) and extracted with ethyl acetate (2 x 250 mL). Combined organic layer was washed with sodium bicarbonate (2 x 250 mL), followed by brine (2 x 100 mL) and dried over sodium sulfate. The organic layer concentrated using rota evaporator to afford a crude mass (40 g) which was purified by fractional distillation under reduced pressure to obtain a regioisomeric mixture of acetates 15.0 g, 26% yield.

[0450] IR (Neat): 2958.2, 2926.5, 2859.4, 1742.5, 1232.6 cm’1

[0451] XH NMR (400 MHz, CDCh): 6 5.25 - 4.98 (m, 2 H), 4.08 - 3.93 (m, 2 H), 2.01 (s, 3 H), 1.62

[0452] - 1.54 (m, 2 H), 1.25 - 1.21 (m, 9 H), 0.98 -0.83 (m, 10 H).

[0453] GC-MS (m / z): 240.1 (M+), 197.2, 180.2 Step-5: Synthesis of a mixture 3,6-dimethylundec-5-en-l-ol (compound 59) and 3,6- dimethylundec-4-en-l-ol (compound 60):

[0454] To a regioisomeric mixture of acetates from step-4 (5.0 g, 20.80 mmol) was added a solution of sodium hydroxide (1.66 g, 41.6 mmol) in water (2.5 mL) and methanol (2.5 ml) over 10 min at 25 °C. The reaction mixture was heated at 100 °C for 5 h and then cooled to 25 °C. Reaction mixture was cooled at room temperature and methanol was evaporated using rota-evaporator. The residue was neutralized with 10% hydrochloric acid (10 mL). Organic layer was separated and washed with water (2 x 20 mL) and saturated brine (2 x 20 mL). The resulting crude was distilled to afford desired alcohol as a mixture of regioisomers 3 g. Distilled on Kugelrohr instrument to afford (1.2 g, 29% yield) clear oil.

[0455] Odor profile: Floral, mild sweet, rosy, green

[0456] IR (Neat): 3348.1, 2957.4, 2925.5, 2858.6, 1409.4 cm’1

[0457] ‘HNMR (400 MHz, CDCh): 8 5.27 - 5.01 (m, 2 H), 3.65 - 3.55 (m, 2 H), 2.25 - 1.99 (m, 3 H), 1.51 - 1.46 (m, 2 H), 1.25 - 1.01 (m, 8 H), 0.97- 0.83 (m, 8 H).

[0458] GC-MS (m / z): 198.2 (M+), 169.2, 128.1

[0459] Step-6: Synthesis of a mixture of 3,6-dimethylundec-5-enal (compound 61) and 3,6-dimethylundec-4-enal (compound 62):

[0460] This compound was synthesized from the mixture obtained in step-5, example 10, using the procedure of step-5 as given in example- 1 :

[0461] Odor profile: tropical aldehydic, green, watery, tender green

[0462] IR (Neat): 2958.4, 2926.0, 2872.3 1726.4 cm’1

[0463] ’H NMR (400 MHz, CDCh): 6 9.69 - 9.67 (m, 1 H), 5.28 - 5.06 (m, 2 H), 2.42 - 2.31 (m, 2 H), 2.01 - 1.94 (m, 2 H), 1.24 - 1.20 (m, 8 H), 1.05 - 0.83 (m, 9 H).

[0464] GC-MS (m / z): 196.2 (M+), 181.2, 165.2, 137.1, 123.1

[0465] Example-11:

[0466] Synthesis of a mixture of 3,6-dimethyldodec-5-enal (compound 67) and 3,6- dimethyldodec-4-enal (compound 68) using 2-methyleneoctanal and isoprenol

[0467] Step-1: Synthesis of 2-methyleneoctanal:

[0468] This compound was synthesized from / / -octanal using the procedure of step-1 as given in example-10:XH NMR (400 MHz, CDCh): 6 0.85 (t, J= 6.8 Hz, 3 H), 1.29-1.26 (m, 6 H), 1.41-1.39 (m, 2 H), 2.23-2.92 (m, 2 H ), 5.96-5.95 (s, 1H), 6.22-6.21 (s, 1H), 9.51 (s, 1H).

[0469] IR (Neat): 2958.7, 2926.9, 2858.2, 1725.3 cm’1

[0470] Step-2: Synthesis of a mixture of 4-methyl-6-(oct-l-en-2-yl)-3,6-dihydro-2H-pyran, 4- methyl-2-(oct-l-en-2-yl)-3,6-dihydro-2H-pyran and 4-methylene-2-(oct-l-en-2- yl)tetr ahydr o-2H- pyran :

[0471] This compound was synthesized from 2-methyleneoctanal and isoprenol using the method described in step-1 in example-10:

[0472] IR (Neat): 2928.4, 2857.6, 1731.8, 1680.6 cm’1

[0473] 1H NMR (400 MHz, CDCh): 8 5.45-5.39 (m, 1 H), 5.03 - 4.84 ( s, 1 H), 4.17-4.16 (m, 1 H), 3.95 - 3.81 (m, 2 H), 2.12 - 2.04 (m, 2 H), 2.02 (m, 1 H) ,1.98 - 1.88 (m, 2 H), 1.68-1.64 (m, 3 H), 1.36-1.25 (m, 8 H), 0.87 - 0.84 (m, 3 H).

[0474] Step-3: Synthesis of 4-methyl-2-(octan-2-yl)tetrahydro-2H-pyran:

[0475] This compound was synthesized from product of step-2, example 11 and using the method described in step-2 in example-10:

[0476] IR (Neat): 2924.9, 2855.1, 2732.6, 1736.4, 1458.5, 1377.5, 1094, 996, 878, 822 cm’1‘HNMR (400 MHz, CDCh): 6 4.09-3.96 (m, 2 H), 3.84 - 3.59 (m, 1 H), 3.39 -3.07 (m, 1 H), 2.29 - 2.00 (m, 1 H), 1.99 -1.97 (m, 2 H), 1.77 - 1.50 (m, 2 H), 1.36 -1.18 ( m, 11 H), 1.04 - 1.03 (m, 2 H), 0.92-0.81 (m, 6 H).

[0477] Step-4: Synthesis of a mixture of 3,6-dimethyldodec-5-en-l-yl acetate and 3,6- dimethyldodec-4-en-l-yl acetate:

[0478] This compound was synthesized from product of step-3, example 11 and using the method described in step-3 in example-10:

[0479] IR (Neat): 2926.8, 2857.7, 1743.9, 1459.0, 1366, 1236, 1047, 970 cm’1

[0480] ’H NMR (400 MHz, CDCh): 6 5.22 - 5.13 (m, 2 H), 4.09 - 3.94 (m, 2 H), 2.58 -2.17 (m, 1 H), 2.15 - 2.02 (m, 1 H), 2.02 (m, 2 H), 1.70- 1.47 ( m, 4 H), 1.23-1.22 (s, 12 H), 0.99 - 0.85 (m, 6 H).

[0481] GC-MS (m / z): 254.1 (M+), 254.1, 224, 194, 166 , 194.

[0482] Step-5: Synthesis of a mixture of 3,6-dimethyldodec-5-en-l-ol (compound 65) and 3,6- dimethyldodec-4-en-l-ol (compound 66): This compound was synthesized from product of step-4, example 11 and using the method described in step-4 in example-10:

[0483] Odor profile: Oily, green, mild sweet, floral.

[0484] IR (Neat): 2958.6, 2926.7, 2859.7, 1741.4, 1231.0 cm’1

[0485] ’H NMR (400 MHz, CDCh): 8 5.28 -5.16 (m, 1 H), 5.09-5.05 (m, 1 H), 3.64 - 3.61 (m, 2H), 2.58 - 2.55 (m, 1 H), 2.39-2.18 (m,l H), 1.59- 1.41 (m, 3 H), 1.23 (m, 8 H), 0.98 -0.84 (m, 9 H).

[0486] GC-MS (m / z): 212.1 (M+), 212,194,166,152,126,109.83

[0487] Step-6 : Synthesis of a mixture of 3,6-dimethyldodec-5-enal (compound 67) and 3,6- dimethyldodec-4-enal (compound 68):

[0488] This compound was synthesized from the mixture obtained in step-5, example 11, using the procedure of step-5 as given in example- 1 :

[0489] (4.0 g, 45% yield) as a colourless liquid.

[0490] Odor profile: Floral, green.

[0491] IR (Neat): 2925.7, 2856.3, 2714.1, 1727, 1457.9, 1376.4, 1078, 970 cm’1

[0492] XH NMR (400 MHz, CDCh): 6 9.70 (s, 1 H), 5.28 - 5.27 (m, 1 H), 5.12 -5.07 (m, 1 H), 3.04 - 3.00 (m, 1 H), 2.71 -2.66 (m, 1 H), 2.43 - 2.29 (m,l H), 2.13 (m, 12 H), 1.05 - 1.01 (m, 3 H), 0.93 - 0.91 (m, 3 H), 0.89 - 0.84 (m, 3 H).

[0493] GC-MS (m / z): 210.1 (M+), 210,195, 179, 166.

[0494] Few compounds encompassed by the scope of the present invention are disclosed herewith. It must be noted that the disclosed compounds do not limit the scope of the present invention.

[0495] The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the disclosure.

[0496] COMPOSITION EVALUATION EXAMPLES:

[0497] Comparison using Example 4 in Citrus Accord: In the following example, various citrus composition accords containing one benchmarking compound was evaluated and compared against a composition accord containing the compound from example 4. Composition A contains compound from example 4, viz mixture of 3- methyldec-4-enal (compound 15) & 3-methyldec-5-enal (compound 16) as 10% w / w solution in IPM (Isopropyl myristate). Composition B contains commercial compound trans-4-decenal, composition C contains only IPM and serves as blank. All above compositions were evaluated in shampoo.

[0498] Addition of 0.5% by weight of the compound from Example 4, viz mixture of 3-methyldec-4- enal (compound 15) & 3-methyldec-5-enal (compound 16) imparted a sparkling and fresh character to the citrus composition. This character was much more in strength than that observed in the citrus compositions B and C. Also, a tangy note was presented in the top notes. Overall performance of the composition A was highly enhanced and superior to the corresponding performances of compositions B and C.

[0499] Comparison using compounds from Example 4 in Rose Accord: In another evaluation, various rose composition accords containing varied benchmarking compounds were evaluated and compared against a composition accord containing the compound from example 4. Composition A contains compound from example 4, viz mixture of 3-methyldec-4-enal (compound 15) & 3-methyldec-5-enal (compound 16) as 10% w / w solution in IPM (Isopropyl myristate). Composition B contains commercial compound trans- 4-decenal, composition C contains only IPM and serves as blank. All above compositions were used in shampoo as well as in fabric softener.

[0500] When compound from Example 4 was dosed at 0.5% w / w in shampoo as well as fabric softener as illustrated in composition A, a well-rounded and more voluminous character was imparted to the composition. Compared to other compositions B which contained commercial compounds trans-4-Decenal, the composition A was more floral, more rosy and had more voluminous effect. Comparison using compounds from Example 2 in Rose Accord: In another evaluation study, various rose composition accords containing varied benchmarking compounds were evaluated and compared against a composition accord containing the compound from example 2.

[0501] In the following Invention, composition A contains compound from example 2, viz mixture of 3,7-dimethyloct-4-en-l-ol (compound 5) and 3,7-dimethyloct-5-en-ol compound 6). Composition B contains commercial compound Citronellol, composition C contains commercial compound geraniol and composition D contains only Dipropylene Glycol and serves as blank.

[0502] When compound from Example 2, viz, mixture of 3,7-dimethyloct-4-en-l-ol (compound 5) and 3,7-dimethyloct-5-en-ol compound 6) was dosed at 30% weight by weight, the accord displays excellent diffusion of fragrance, it also gives rosy characteristics with natural feel. Additionally, it also imparts natural honey effect to composition A compared with the other benchmark raw materials of composition B and composition C.

[0503] On the other hand, equal quantity of Citronellol (composition B) & Geraniol (composition C) when used in the above accord, impart rosy, powdery effect but with a synthetic feel.

[0504] Comparison using compounds from Example 2 in Fruity Accord:

[0505] In another evaluation study, various fruity composition accords containing varied benchmarking compounds were evaluated and compared against a composition accord containing the compounds from example 2, viz a mixture of 3,7-dimethyloct-4-enal (compound 7) and 3,7-dimethyloct-5-enal (compound 8). In the following Invention, composition A is blank as Dipropylene Glycol, Composition B contains commercial compound Cyclal and composition C contains example 2 as a mixture of 3,7-dimethyloct-4-enal and 3,7-dimethyloct-5-enal. Clearly the introduction of 5% weight-by-weight of 3,7-dimethyloct-4-enal and 3,7- dimethyloct-5-enal in composition C, gives better diffusion of fragrance and imparts crunchy, peely, apple character. It also adds volumes to toppy fruity accord.

[0506] On the other hand, when Cyclal is used in 10% weight-by-weight in composition B, it merely affords fruity top character to the accord.

Claims

CLAIMS1. Process for the preparation of compounds of formula (I).A = -CH2OAC, -CH2OH, -CHO dotted line represents a double or single bondR-i is an alkyl or alkylidene group comprising the steps of a. Reacting an aldehyde of formula (II)II with an alcohol of formulaIsoprenol to get a compound of formula (III)b. Reacting the compound of formula (III) with Ra-Ni and hydrogen to get a compound of formula (IV)c. Reacting the compound of formula (IV) with acetic anhydride to get a compound of formula (V) which is the compound of formula (I) wherein A represents -CH2OACd. Optionally and additionally reacting the compound of formula (V) with sodium hydroxide and / or potassium hydroxide in water to get a compound of formula (VI) which is the compound of formula (I) wherein A represents -CH2OHe. optionally and additionally oxidating the compound of formula (VI) employing (2, 2,6,6- Tetramethylpiperidin-1 -yl)oxyl (TEMPO) or 4-hydroxy-TEMPO along with N- chlorosuccinimide to obtain a compound of formula (VII) which is the compound of formula (I) wherein A represents -CHO2. Process for the preparation of compounds of formula (I) according to claim 1 wherein the compound of formula (VI) is hydrogenated using Ra-Ni catalyst to get a compound of formula (VIII) which is the compound of formula (I) wherein A represents -CH2OH3. Process for the preparation of compounds of formula (I) according to claim 2 wherein the compound of formula (VIII) is subjected to a TEMPO-mediated oxidation to afford compound of formula (IX) which is the compound of formula (I) wherein A represents -CHO4. Process for the preparation of compounds of formula (I) according to any of the preceding claims wherein R2 is an alkyl group or an alkenyl group.

5. Process for the preparation of compounds of formula (I) according to any of the preceding claims wherein Ri is selected from alkyl or alkylidene groups having up to 9 carbon atoms with a linear or branched chain.

6. Process for the preparation of compounds of formula (I) according to any of the preceding claims wherein R2 is an alkyl group having 2, 3, 4, 5, 6, 7, 8 or 9 carbon atoms or an alkenyl group having 2, 3, 4, 5, 6, 7, 8 or 9 carbon atoms.

7. Process for the preparation of compounds of formula (I) according to claim 1 wherein Ri is selected from methyl, ethyl, w-propyl, isopropyl, / / -butyl, isobutyl, w-pentyl, w-hexyl, n-heptyl, n-octyl, n-nonyl, methylidene, ethylidene, propylidene, isopropylidene, butylidene, isobutylidene, pentylidene, hexylidene, heptylidene, octylidene, or nonylidene.

8. Process for the preparation of compounds of formula (I) according to claim 1 wherein step a is performed in presence of an acid catalyst or para-toluene sulfonic acid.

9. Process for the preparation of compounds of formula (I) according to claim 1 wherein step c is performed in the presence of an acid catalyst or para-toluene sulfonic acid.

10. Process for the preparation of compounds of formula (I) according to claim 1 wherein sodium hydroxide in water is used in step d.

11. Mixture of at least two compounds of formula (I) and / or at least two stereoisomers and / or regioisomers of the compounds of formula (I)A = -CH2OAC, -CH2OH, -CHO dotted line represents a double or single bondR-i is an alkyl or alkylidene group obtainable by the process of claim 1.

12. Mixture of two or four or more stereoisomers and / or regioisomers selected fromwherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain or an alkyl group with C2 to C9 atoms, and / or selected fromtrans cis wherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain or an alkyl group with C2 to C9 atoms and R3 and R4 are selected from H and alkyl groups with a linear or branched chain such that the sum of carbon atoms in R3 and R4 is from 2 carbon atoms to up to 8 carbon atoms, obtainable by the process of claim 1.

13. Mixture of the two stereoisomers and / or regioisomers of formulaewherein A = -CH2OAC, -CH2OH or -CHO and Ri is an alkyl group having up to 9 carbon atoms with a linear or branched chain or an alkyl group with C2 to C9 atoms, and / or from formulaewherein A = -CH2OAC, -CH2OH or -CHO and R3 and R4 are selected from H and alkyl groups with a linear or branched chain such that the sum of carbon atoms in R3 and R4 is from 2 carbon atoms to up to 8 carbon atoms, obtainable by the process of claim 1.

14. Mixture of odorous compounds of formula (I)A = -CH2OAC, -CH2OH, -CHO dotted line represents a double or single bondR-i is an alkyl or alkylidene group selected from any of the following mixtures:

15. Fragrance, flavor and / or deodorizing / masking compositions comprising a mixture according to any of claims 11 to 14 conferring aldehydic, watery, floral, green type notes.

16. Fragrance, flavor and / or deodorizing / masking composition according to claim 15 wherein the content of the compound of formula (I) is at least 0.1 wt. %.

17. Fragrance, flavor and / or deodorizing / masking composition according to claim 16 wherein the content of the compound of formula (I) is at least 1 wt. %.

18. Fragrance, flavor and / or deodorizing / masking composition according to any of claims 15 to 17 wherein the content of the compound of formula (I) is below 50 wt. %.

19. Fragrance, flavor and / or deodorizing / masking composition according to claim 18 wherein the content of the compound of formula (I) is below 25 wt. %.

20. Fragrance, flavor and / or deodorizing / masking composition according to any of claims 15 to 19 comprising at least one ester and / or one alcohol, or at least a mixture of ester and alcohol, wherein the total content of the compound(s) of formula (I) together with the ester(s) and alcohol(s) is superior to 25 wt%.

21. Fragrance, flavor and / or deodorizing / masking composition according to claim 20 wherein the total content of the compound(s) of formula (I) together with the ester(s) and alcohol(s) is superior to 50 wt%.

22. Use of a fragrance, flavour and / or deodorizing / masking composition according to any of claims 15 to 21 in a perfumed or flavoured product.

23. Use of a mixture according to any of claims 11 to 14 in a perfumed or flavoured product.

24. Process according to any of claims 1 to 10 for the preparation of mixture according to any of claims 11 to 14.

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