(R,E)-3,7-Dimethylnon-6-enal, its isomeric mixture and its use in perfumery

Abstract

Provided is a compound of formula (R,E)-(Ia) which is (R,E)-3,7-dimethylnon-6-enal, an isomeric mixture of said compound and its use in perfumery.

Description

[Technical field]

[0001] Technical Field The present invention generally relates to novel organic compounds and their use as fragrance ingredients.The present invention also relates to fragrance compositions and to consumer products that contain the compounds.It further relates to a method of improving, enhancing or modifying the consumer product base by adding the compounds. [Background technology]

[0002] background Citral (3,7-dimethyloct-2,6-dienal) and citronellal (3,7-dimethyloct-6-enal) are known compounds with citrus, lemon-like odors. Both are used in perfumery, however, citral is a known allergen. In general, citrus notes are complex and can have many different aspects. It would therefore be desirable to provide new or improved fragrance compounds having citrus and optionally other notes. Summary of the Invention

[0003] summary According to a first aspect of the present invention, novel compounds having citrus and floral aroma notes are provided. According to a second aspect of the present invention, there is provided an isomeric mixture comprising a novel compound. According to a third aspect of the present invention there is provided the use of the novel compounds or isomer mixtures as fragrance ingredients.

[0004] According to a fourth aspect of the present invention, there is provided a fragrance composition and consumer product comprising the novel compound or isomer mixture. Furthermore, the fragrance composition and consumer product may contain an alcohol.

[0005] According to a fifth aspect of the present invention there is provided a method of improving, enhancing or modifying a consumer product base by means of the addition of a novel compound to the base.

[0006] Certain embodiments of any of the aspects of the invention may provide one or more of the following advantages. - Provision of novel fragrance compounds with citrus and floral aroma notes; Providing compounds that have no allergenic properties, • Providing high performance compounds with low odor threshold.

[0007] The details, examples, and preferences provided with respect to one or more specific aspects of the invention will be described further herein and apply equally to all aspects of the invention. Any combination of any embodiment, example, and preference described herein in all variations thereof is covered by the present invention unless otherwise indicated herein or clearly contradicted by context. [Brief description of the drawings]

[0008] [Figure 1] Compound Ia (a mixture of four stereoisomers) exhibited a BOD (biological oxygen demand) of 70% (60 days, readily biodegradable). [Diagram 2] The mixture of Example 3 (aldehyde mixtures Ia, Ib, Ic, II) exhibited a BOD (biological oxygen demand) of 87% (readily biodegradable for 60 days). Detailed Description of the Invention

[0009] Detailed Description The present invention is based on the surprising discovery that homologs of citronellal formally elongated with one methyl group are fragrance compounds with significantly different odor descriptions and exceptionally enhanced performance.

[0010] In a first aspect of the present invention, there is provided a compound represented by formula (R,E)-(Ia), which is (R,E)-3,7-dimethylnon-6-enal. [ka]

[0011] Said compound is a useful fragrance ingredient, surprisingly possessing citrus and floral odor notes.In addition, it has an exceptionally low gas chromatography (GC) threshold of 0.013ng, compared with the GC threshold of 4.0ng for citral or 2.2ng for citrolanel.Such performance molecules, with a GC threshold lower by a factor of 100 than related structures, can be used in lower doses, thereby reducing the required amount of compound.The perfumery benefits of the compounds of the present invention depend on stereochemistry: only one of the four stereoisomers is a strong odorant, while the others only show very weak odorant properties.

[0012] For example, compound (R,E)-(Ia) can be employed as an at least partial replacement for citral, at least lowering the amount of citral required, thereby reducing color problems associated with citral and minimizing the amount of allergenic compounds.

[0013] 3,7-Dimethylnon-6-enal has been reported before. For example, its preparation is disclosed in DE 2050677 A1. However, its fragrance properties are not described.

[0014] The compounds (R,E)-(Ia) of the present invention can be used as pure stereoisomers or as mixtures with one or more of its stereoisomers, for example in the group of diastereoisomers.In contrast to the compounds of the present invention, the other stereoisomers have much weaker odor properties.

[0015] (S,E)-3,7-Dimethylnon-6-enal ((S,E)-(Ia)) has a GC threshold of 1.4 ng and a waxy, fatty odor with citrus and floral rose notes. (R,Z)-3,7-Dimethylnon-6-enal ((R,Z)-(Ia)) has a GC threshold of 1.2 ng and its odor is described as waxy, citrus, fruity. (S,Z)-3,7-Dimethylnon-6-enal ((S,Z)-(Ia)) has a GC threshold of 0.75 ng and a waxy, fatty, plastic odor with citrus notes.

[0016] Other isomers do not possess significant odor, so they can be accepted as admixtures with the compounds of the present invention.The use of such admixtures can avoid the cost of isomer separation, and can reduce the overall production cost.Resolving stereoisomers adds complexity to the preparation and purification of compounds, so it is preferred for economic reasons to use compounds as mixtures of their stereoisomers.However, if it is desired to prepare individual stereoisomers, this can be achieved according to methods known in the art, such as stereoselective synthesis, preparative HPLC and GC.

[0017] Thus, in a further aspect of the present invention there is provided an isomeric mixture (referred to as isomeric mixture in the following text) comprising (R,E)-3,7-dimethylnon-6-enal ((R,E)-(Ia)) and at least another compound selected from the group consisting of (S,E)-3,7-dimethylnon-6-enal ((S,E)-(Ia)), (R,Z)-3,7-dimethylnon-6-enal ((R,ZE)-(Ia)) and (S,Z)-3,7-dimethylnon-6-enal ((S,Z)-(Ia)).

[0018] In another aspect of the invention, the compound of formula (R,E)-(Ia) is provided in highly enriched or essentially pure form and contains low amounts or is essentially free of the compounds (S,E)-(Ia), (R,Z)-(Ia) and / or (S,Z)-(Ia), meaning that the compound of formula (R,E)-(Ia) is present in at least 90% by weight, in particular at least 95% by weight, more in particular at least 98% by weight, even more in particular 99% by weight or more.

[0019] In another aspect of the present invention, there is provided an isomeric mixture comprising a substantial amount of a compound of formula (R,E)-(Ia) together with compounds (S,E)-(Ia), (R,Z)-(Ia) and / or (S,Z)-(Ia). This means that the compound of formula (IIa) is present in at least 20% by weight, in particular at least 30% by weight, more particularly at least 40% by weight, and even more particularly 50% by weight or more. The weight ratio of the compound of formula (R,E)-(Ia) to the total of the compounds of formula (S,E)-(Ia), formula (R,Z)-(Ia) and / or formula (S,Z)-(Ia) in the isomeric mixture may range from about 2:8 to about 99:1. For example, the isomeric mixture may contain (R,E)-(Ia), (S,E)-(Ia), (R,Z)-(Ia), and (S,Z)-(Ia) in a 1:1:1:1 ratio.

[0020] In another aspect of the invention, a mixture of the (R)-isomers (R,E)-(Ia) and (R,Z)-(Ia) is provided in pure or enantio-enriched form. In another aspect of the invention, a mixture of the (E)-isomers (R,E)-(Ia) and (S,E)-(Ia) is provided in pure form or in enantiomerically enriched form at the double bond.

[0021] In a further aspect of the invention, there is provided the use of a compound of formula (R,E)-(Ia), or of an isomeric mixture comprising (R,E)-(Ia) and at least one other compound selected from the group consisting of (S,E)-(Ia), (R,Z)-(Ia) and / or (S,Z)-(Ia), as a fragrance ingredient: In another aspect of the present invention, there is provided a fragrance composition comprising a compound represented by formula (R,E)-(Ia), or an isomeric mixture comprising (R,E)-(Ia) and at least one other compound selected from the group consisting of (S,E)-(Ia), (R,Z)-(Ia) and / or (S,Z)-(Ia).

[0022] The compounds or isomer mixtures of the present invention may be used alone or in combination with known odorant molecules selected from a wide range of natural and currently available synthetic molecules such as essential oils, alcohols, aldehydes and ketones, ethers and acetals, esters and lactones, macrocycles and heterocycles, and / or admixed with one or more ingredients or excipients conventionally used in conjunction with odorants in perfume compositions, such as carrier materials and other auxiliaries commonly used in the art.

[0023] As used herein, "carrier material" means a substance that is practically neutral from the aroma point of view, ie a material that does not significantly alter the organoleptic properties of the aroma.

[0024] The term "auxiliary" refers to an ingredient that may be employed in a fragrance composition for reasons not specifically related to the olfactory performance of said composition. For example, an adjuvant may be an ingredient that acts as an adjuvant for processing the fragrance ingredient(s) or ingredients, or the composition containing said ingredient(s), or it may improve the handling or storage of the fragrance ingredient or the composition containing it. It may also be an ingredient that provides additional benefits, such as imparting color or texture. It may also be an ingredient that imparts light resistance or chemical stability to one or more ingredients contained in the fragrance composition. A detailed description of the nature and type of adjuvants commonly used in fragrance compositions containing them cannot be exhaustive, but it must be mentioned that said ingredients are well known to those skilled in the art.

[0025] As used herein, "perfume composition" means any composition comprising a compound according to formula (R,E)-(Ia), or an isomer mixture, and a base material, e.g., diluents conventionally used in conjunction with fragrances, such as diethyl phthalate (DEP), dipropylene glycol (DPG), isopropyl myristate (IPM), pentane-1,2-diol, triethyl citrate (TEC) and alcohol (e.g., ethanol). Optionally, the composition may include an antioxidant adjuvant. The antioxidant may be selected from Tinogard® TT (BASF), Tinogard® Q (BASF), tocopherol (including its isomers, CAS 59-02-9; 364-49-8; 18920-62-2; 121854-78-2), 2,6-bis(1,1-dimethylethyl)-4-methylphenol (BHT, CAS 128-37-0), and the related phenol, hydroquinone (CAS 121-31-9).

[0026] The following list includes examples of known odorant molecules that may be combined with a compound or isomeric mixture according to formula (R,E)-(Ia): essential oils and extracts, for example bead onion, costus root oil, oak moss absolute, geranium oil, wood moss absolute, fruit oils such as basil oil, bergamot oil and mandarin oil, myrtle oil, palmarosa oil, patchouli oil, petitgrain oil, jasmine oil, rose oil, sandalwood oil, absinthe oil, lavender oil and / or ylang-ylang oil, Alcohols, such as cinnamic alcohol ((E)-3-phenylprop-2-en-1-ol); cis-3-hexenol ((Z)-hex-3-en-1-ol); citronellol (3,7-dimethyloct-6-en-1-ol); dihydromyrcenol (2,6-dimethyloct-7-en-2-ol); Ebanol™ ((E)-3-methyl-5-(2,2,3-trimethylcyclopenta[1,2-diol], 1 ... -3-en-1-yl)pent-4-en-2-ol;Eugenol (4-allyl-2-methoxyphenol);Ethyl linalool ((E)-3,7-dimethylnona-1,6-dien-3-ol);Farnesol ((2E,6Z)-3,7,11-trimethyldodeca-2,6,10-trien-1-ol);Geraniol ((E)-3,7-dimethylocta-2,6-dien-1-ol);Super Muguet™ ((E)-6-ethyl-3-methyloct-6-en-1-ol); Linalool (3,7-dimethylocta-1,6-dien-3-ol); Menthol (2-isopropyl-5-methylcyclohexanol); Nerol (3,7-dimethyl-2,6-octadien-1-ol); Phenylethyl alcohol (2-phenylethanol); Rhodinol™ (3,7-dimethyloct-6-en-1-ol); Sandalore™ (3-methyl terpineol (2-(4-methylcyclohex-3-en-1-yl)propan-2-ol); or Timberol™ (1-(2,2,6-trimethylcyclohexyl)hexan-3-ol); 2,4,7-trimethylocta-2,6-dien-1-ol, and / or [1-methyl-2(5-methylhex-4-en-2-yl)cyclopropyl]-methanol; Aldehydes and ketones, such as anisaldehyde (4-methoxybenzaldehyde); alpha amyl cinnamaldehyde (2-benzylideneheptanal); Georgywood™ (1-(1,2,8,8-tetramethyl-1,2,3,4,5,6,7,8-octahydronaphthalen-2-yl)ethanone); hydroxycitronellal (7-hydroxy-3,7-dimethyloctanal); Iso E Super® (1-(2,3,8,8-tetramethyl-1,2,3,4,5,6,7,8-octahydronaphthalen-2-yl)ethanone); Isoraldeine® ((E)-3-methyl-4-(2,6,6-trimethylcyclohex-2-en-1-yl)but-3-en-2-one); Hedione® (methyl 3-oxo-2-pentyl cyclopentane acetate); 3-(4-isobutyl-2-methylphenyl)propanal; maltol; methyl cedryl ketone; methyl ionone; verbenone; and / or vanillin; Ethers and acetals, such as Ambrox® (3a,6,6,9a-tetramethyl-2,4,5,5a,7,8,9,9b-octahydro-1H-benzo[e][1]benzofuran); geranyl methyl ether ((2E)-1-methoxy-3,7-dimethylocta-2,6-diene); rose oxide (4-methyl-2-(2-methylprop-1-en-1-yl)tetrahydro-2H-pyran); and / or Spirambrene® (2',2',3,7,7-pentamethylspiro[bicyclo[4.1.0]heptane-2,5'-[1,3]dioxane]); ● Esters and lactones, such as benzyl acetate; cedryl acetate ((1S,6R,8aR)-1,4,4,6-tetramethyloctahydro-1H-5,8a-methanoazulen-6-yl acetate); γ-decalactone (6-pentyltetrahydro-2H-pyran-2-one); Helvetolide® (2-(1-(3,3-dimethylcyclohexyl)ethoxy)-2-methylpropylpropionate); γ-undecalactone (5-heptyloxolan-2-one); and / or vetiberyl acetate ((4,8-dimethyl-2-propan-2-ylidene-3,3a,4,5,6,8a-hexahydro-1H-azulen-6-yl) acetate); Macrocycles, such as ambrettolide ((Z)-oxacycloheptadecan-10-en-2-one); ethylene brassylate (1,4-dioxacycloheptadecane-5,17-dione); and / or Exaltolide® (16-oxacyclohexadecane-1-one); and • Heterocycles, for example isobutylquinoline (2-isobutylquinoline).

[0027] Furthermore, there is provided a compound represented by formula (R,E)-(Ia), or an isomeric mixture comprising (R,E)-(Ia) and at least one other compound selected from the group consisting of (S,E)-(Ia), (R,Z)-(Ia) and / or (S,Z)-(Ia), as well as a fragrance composition comprising at least one compound selected from the group consisting of compounds represented by formulae (Ib), (Ic) and (II). [ka] In the formula, the wavy bond indicates an unspecified configuration of the adjacent double bonds and the star indicates the stereocenter of the C atom.

[0028] The compounds represented by formula (Ib), (Ic) and (II) have at least one stereocenter or at least one double bond at the C atom.Therefore, the compounds exist in up to four isomeric forms, varying in the configuration of the stereocenter and / or double bond.The compounds as described herein occur as any of the possible isomers, or as a mixture of some or all of the possible isomers.

[0029] The compounds of formula (Ib) and (Ic) do not have a strong odor and therefore can be accepted in admixture with compound (R,E)-(Ia), when they arise as by-products during the production of compound (R,E)-(Ia), and when their separation adds cost.

[0030] The compound of formula (II) has a fatty, waxy, floral, rose-citrus odor and is also very potent (GCTH 0.046 ng). In mixtures with compound (R,E)-(Ia), powerful blends with broader olfactory activity facets can be provided. For example, perfumers prefer perfume compositions containing up to 3% by weight of a compound of formula (R,E)-(Ia) or an isomeric mixture of formula (R,E)-(Ia) and a compound of formula (II).

[0031] In another aspect of the present invention, there is provided a compound of formula (R,E)-(Ia) or an isomeric mixture comprising (R,E)-(Ia) and at least one other compound selected from the group consisting of (S,E)-(Ia), (R,Z)-(Ia) and / or (S,Z)-(Ia), as well as a fragrance composition comprising at least one compound of formula (III). [ka] During the ceremony, [ka] indicates a carbon-carbon single or double bond, a wavy bond, when present, indicates an unspecified configuration of the adjacent double bonds; and R1, R2 and R3 are independently selected from H or Me; Alternatively, in which R1 is H or Me, and R2 and R3 together with the carbon atom to which they are attached form a cyclopropyl ring.

[0032] The compound of formula (III) can have up to three stereocenters and / or at least one double bond at the C atom.Therefore, the compound can exist in up to 16 isomeric forms, varying in the configuration of stereocenters and / or double bonds.The compound as described herein can occur as any of the possible isomers, or as a mixture of some or all of the possible isomers.

[0033] The compound of formula (III) is an alcohol derivative of compound (Ia) and has a floral note and a low odor threshold. The compound of formula (III) in combination with compound (R,E)-(Ia) provides a novel floral accord.

[0034] Compound Ia refers to an isomer of unspecified configuration or to a mixture of isomers as described above. For example, the fragrance composition referred to above further comprises at least one compound represented by formula (III) selected from the group consisting of compounds represented by formula (IIIa), formula (IIIb), formula (IIIc), and formula (IIId). [ka] In the formula, the wavy bond, when present, indicates an unspecified configuration of the adjacent double bond.

[0035] Furthermore, the present invention provides a fragrance composition comprising a compound represented by formula (R,E)-(Ia), or an isomeric mixture comprising (R,E)-(Ia) and at least one other compound selected from the group consisting of (S,E)-(Ia), (R,Z)-(Ia) and / or (S,Z)-(Ia), and at least one compound selected from the group consisting of compounds represented by formulae (Ib), (Ic), (II) and (III).

[0036] Some of the compounds of formula (III) are known, while some have not been reported before and are therefore novel. Thus, in another aspect of the present invention, there is provided a compound of formula (III): [ka] During the ceremony, [ka] indicates a carbon-carbon single or double bond, a wavy bond, when present, indicates an unspecified configuration of the adjacent double bonds; and R1, R2 and R3 are independently selected from H or Me; or wherein R1 is H or Me, and R2 and R3 together with the carbon atom to which they are attached form a cyclopropyl ring; However, the compounds are not 3,7-dimethylnonan-1-ol and 3,7-dimethylnon-6-en-1-ol.

[0037] For example, the compound represented by formula (III) can be selected from the group consisting of compounds represented by formulas (IIIa), (IIIb), and (IIId): [ka] In the formula, the wavy bond, when present, indicates an unspecified configuration of the adjacent double bond.

[0038] The compound represented by formula (IIIa) (2,3,7-trimethylnon-6-en-1-ol) has a floral rose odor and a GC threshold of 0.04 ng. The compound represented by formula (IIIb) (2-methyl-2-(4-methylhex-3-en-1-yl)cyclopropyl)methanol) has a floral rose fruity lychee odor and a GC threshold of 1.2 ng. And the compound represented by formula (IIId) (4,8-dimethyldec-7-en-2-ol) has a floral pomerol green odor but a relatively high GC threshold of 15 ng.

[0039] In another aspect of the present invention, there is provided a fragrance composition comprising at least one compound represented by formula (III).

[0040] In another aspect of the present invention, there is provided a compound of formula (R,E)-(Ia) or an isomeric mixture comprising (R,E)-(Ia) and at least one other compound selected from the group consisting of (S,E)-(Ia), (R,Z)-(Ia) and / or (S,Z)-(Ia), as well as a fragrance composition comprising at least one compound of formula (X). [ka] During the ceremony, [ka] indicates a carbon-carbon single or double bond, The wavy bond indicates an unspecified configuration of adjacent double bonds; The star indicates the stereocenter at the C atom.

[0041] The compound of formula (X) in admixture with compound (R,E)-(Ia) provides a new citrus accord.

[0042] Compounds of formula (X) have been used as intermediates in the preparation of compounds of formula (III) and have also been found to have interesting fragrant properties. Thus, in another aspect of the present invention, there is provided a compound of formula (X), [ka] During the ceremony, [ka] indicates a carbon-carbon single or double bond, The wavy bond indicates an unspecified configuration of adjacent double bonds; The star indicates the stereocenter at the C atom.

[0043] For example, the compound represented by formula (X) can be selected from the group consisting of 3,7-dimethyl-2-methylenenon-6-enal and 2,3,7-trimethylnon-6-enal.

[0044] In yet another aspect of the present invention, there is provided a consumer product comprising a compound of formula (R,E)-(Ia), or an isomer mixture or a fragrance composition as defined above, and a consumer product base.

[0045] The consumer product is selected from, for example, fine fragrances, personal care products (body care products, cosmetic products), fabric care products, home care products, and air care products. As used herein, "consumer product base" means a composition for use as a consumer product that fulfills a specific function, such as cleaning, softening, and care.

[0046] Personal care products to which the compound of formula (R,E)-(Ia) or a mixture containing it can be added include, for example, all kinds of body care products. Products of particular interest are hair care products, such as shampoos, conditioners, and hairsprays, as well as skin care products, such as lotions or creams. Furthermore, the compound of formula (R,E)-(Ia) or a mixture containing it can be added to soaps, bath and shower gels, and deodorants. The compound of formula (R,E)-(Ia) or a mixture containing it can also be added to cosmetics.

[0047] Home care products to which the compound of formula (R,E)-(Ia) or a mixture containing it can be added include all kinds of detergents, window cleaners, hard surface cleaners, all-purpose cleaners, and furniture polishes. Preferably, the products are liquid, for example fabric cleaners or conditioner compositions.

[0048] The compounds according to formula (R,E)-(Ia), or isomeric mixtures containing it, may be used in a wide range of perfumed consumer products, for example 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 may be employed in widely varying amounts, depending on the particular article, and the nature and amount of other fragrance ingredients. The proportion is typically from 0.0001 to 5% by weight of the article. In one embodiment, the compounds of the present invention or isomeric mixtures containing (R,E)-(Ia) may be employed in fabric softeners in an amount of from 0.001 to 0.3% by weight (for example, 0.01 to 0.1% by weight, including 0.05). In another embodiment, the compound (R,E)-(Ia) or an isomeric mixture containing (R,E)-(Ia) may be used in consumer products such as shampoos, fabric softeners or fabric detergents as well as fine perfumes at 0.001 to 30% by weight (for example up to about 10% by weight or up to 20% by weight), more preferably between 0.01 and 5% by weight. However, these values ​​are given by way of example only, since a skilled perfumer may also achieve effects or create new accords at lower or higher concentrations.

[0049] In one embodiment, a consumer product is provided that includes an acceptable amount of the compound (R,E)-(Ia) or an isomeric mixture that includes (R,E)-(Ia). For example, a fragranced article may include 0.000001% to 90% by weight (including 0.00001% by weight; 0.0001%, 0.001%, 0.01%, 0.05%, 0.1%, 0.5%, 1%, 5%, 8%, 10%, 15%, 20%, 25%, 30%, 50%, 60%, 65% by weight) of the compound or isomeric mixture based on the total weight of the article.

[0050] The compound (R,E)-(Ia) or an isomeric mixture comprising it may be employed in a consumer product base by directly mixing the compound of the present invention, or a perfume composition comprising the compound (R,E)-(Ia) or an isomeric mixture comprising the compound (R,E)-(Ia), or a mixture thereof, with the consumer product base, or it may be encapsulated in an earlier step with an entrapment material, for example polymers, capsules, microcapsules and nanocapsules, liposomes, film formers, absorbents such as carbon or zeolites, cyclic oligosaccharides and mixtures thereof, and then mixed with the consumer product base.

[0051] Thus, in a further aspect, the present invention additionally provides a method for the preparation of a consumer product comprising incorporating the compound (R,E)-(Ia) or an isomeric mixture comprising (R,E)-(Ia) as a fragrance ingredient using conventional techniques and methods, either by directly mixing the compound into the consumer product base, or by mixing a perfume composition comprising the compound (R,E)-(Ia) or an isomeric mixture comprising (R,E)-(Ia), which may be mixed into the consumer product base. By the addition of an olfactory acceptable amount of the compound of the present invention as described above, the odor notes of the consumer product base will be improved, conferred, enhanced or modified.

[0052] Thus, the present invention also provides, in another aspect, a method of improving, imparting, enhancing or modifying a consumer product base by the addition thereto of an olfactory acceptable amount of compound (R,E)-(Ia), or an isomer mixture or fragrance composition comprising compound (R,E)-(Ia).

[0053] In a further aspect, the present invention also provides a method of improving, imparting, enhancing or modifying a consumer product base by the addition thereto of an olfactory acceptable amount of a compound of formula (III), or a fragrance composition comprising a compound of formula (III).

[0054] The compounds of formula (R,E)-(Ia) and other compounds can be prepared in different processes, for example by oxidation of the corresponding primary alcohol (IV). The corresponding primary alcohols can be obtained in a two-step process from ethyl linalool (V) via ethyl geraniol / ethyl nerol (VI). [ka]

[0055] The primary alcohols can be obtained in the form of individual isomers or as a mixture of further separated isomers by stereoselective synthesis. For example, a mixture of alcohol isomers (IV) was converted to the corresponding 3,7-dimethylnon-6-en-1-yl 4-nitrobenzoic acid (VII), allowing separation into the individual isomers by SFC (supercritical fluid chromatography), followed by ester hydrolysis to the individual compounds (R,E)-(IV), (S,E)-(IV), (R,Z)-(IV), and (S,Z)-(IV). [ka]

[0056] In one embodiment, the starting materials of the process for preparing the compound of formula (R,E)-(Ia) are obtained from renewable sources. Such starting materials and the final products are also accessible from renewable sources.

[0057] In a further aspect, the compounds of the invention are biodegradable as demonstrated by the manometric respirometry test (OECD Guideline for the Testing of Materials No. 301F, Paris, 1992).

[0058] The invention will now be further described with reference to the following non-limiting examples, which are for illustrative purposes only, it being understood that variations and modifications can be made by those skilled in the art. EXAMPLES

[0059] example: General: All products were purified after workup either by flash chromatography (FC) or distillation. Mixtures of heptane and methyl tert-butyl ether (MTBE) were used as eluents unless otherwise stated. 1 H and 13 C NMR spectra were measured in C6D6 or CDCl3. 1H NMR spectra were referenced to residual hydrogen signals of the deuterated solvents (1H 7.27 ppm, 13C 77.0 ppm for CDCl3, 1H 7.16 ppm, 13C 128.4 ppm for C6D6) and are reported as: chemical shifts (δ ppm), coupling constants J (Hz). GC-MS analyses were performed on an MSD5975 mass spectrometer and are reported as m / z listings (relative magnitudes). Electron ionization (EI) was performed at 70 eV. Odor descriptions refer to the odor of isomeric mixtures of compounds unless otherwise stated.

[0060] Example 1: Synthesis of all four isomers of 3,7-dimethylnon-6-enal: (R,E)-(Ia), (S,EE)-(Ia), (R,Z)-(Ia), and (S,Z)-(Ia). a) Preparation of 3,7-dimethylnon-6-en-1-ol (IV) Ethyl citronellol (IV) is prepared in a two-step process starting from ethyl linalool (V) via ethyl geraniol / ethyl nerol (VI). i) 3,7-dimethylnona-2,6-dien-1-ol (VI) Under N2, a 1000 mL three-necked round bottom flask equipped with a condenser was charged with ethyl linalool (V, 637.8 g, 3.79 mol), VO(OSiPh3)3 (20.1 g, 0.022 mol) and PhMe (139 g) and the solution was brought to reflux (heating plate set at 110 °C). The progress of the reaction was followed by GC until an equilibrium mixture of 70:30 ethyl linalool:ethyl geraniol / ethyl nerol (3,7-dimethylnona-2,6-dien-1-ol) was observed. After a total reaction time of 3 h, the reaction mixture was cooled to room temperature. PhMe was removed to give a crude light brown liquid (667 g). The reaction mixture was passed through a wiped film evaporator (length = 16 cm, OD 5.5 cm, 80 °C, 0.04 mbar) to provide recovered VO(OSiPh3)3 (17 g) and crude material (ethyl linalool + ethyl geraniol / ethyl nerol mixture) (562.8 g). The crude material was filtered and fractionated (Sulzer packed column (length = 50 cm, ID 30 mm)) to give ethyl linalool (250.1 g) and then ethyl geraniol / ethyl nerol (IV, 92 g, 100% purity, 48%) as a mixture of four isomers in the ratio of 1:3.36:3.51:5.59 as separated yields.

[0061] Mixtures of E / E, E / Z, Z / E and Z / Z isomers: 1 H-NMR (CDCl3, 400MHz): δ = 5.47 - 5.37 (m, 4 x 1H), 5.14 - 5.03 (m, 4 x 1H), 4.14 (d, J=6.8 Hz, 2 x 2H), 4.11 - 4.07 (m, 2 x 2H), 2.16 - 1.94 (m, 4 x 6H), 1.89 (br s, 4 x 1H), 1.75 (m, 2 x 3H), 1.67 (m, 4 x 3H), 1.60 (s, 2 x 3H), 1.00 - 0.94 (m, 4 x 3H) ppm 1313C-NMR (CDCl3, 100 MHz): δ = 139.6 (s), 139.5 (s), 139.34 (s), 139.28 (s), 137.9 (s), 137.7 (s), 137.3 (s), 137.1 (s), 124.43 (d), 124.37 (d), 123.42 (d), 123.35 (d), 122.3 (d), 122.1 (d), 59.1 (t), 58.78 (t), 58.76 (t), 39.8 (t), 39.5 (t), 32.22 (t), 32.19 (t), 31.9 (t), 26.3 (t), 26.2 (t), 26.1 (t), 25.9 (t), 24.7 (t), 24.6 (t), 23.3 (q), 22.72 (q), 22.68 (q), 16.1 (q), 15.8 (q), 12.73 (q), 12.69 (q), 12.67 (q), 12.6 (q) ppm.

[0062] E / E isomer (major): 13 13C-NMR (CDCl3, 100 MHz): δ = 139.3 (s), 137.1 (s), 123.4 (d), 122.3 (d), 59.1 (t), 39.5 (t), 32.2 (t), 26.2 (t), 16.1 (q), 15.8 (q), 12.7 (q) ppm. Peak 1. MS (EI, Rt 6.43 min., 70 eV): 168 (1, [M]+·), 121 (9), 93 (17), 84 (14), 83 (33), 67 (15), 55 (100), 53 (10), 41 (39), 39 (15), 29 (11). Peak 2. MS (EI, Rt 6.51 min., 70 eV): 168 (1, [M]+·), 121 (9), 93 (18), 84 (14), 83 (35), 67 (15), 55 (100), 53 (10), 41 (38), 39 (14), 29 (10). Peak 3.MS (EI, Rt 6.62 min., 70 eV): 168 (0, [M]+·), 137 (9), 93 (9), 84 (8), 83 (37), 67 (13), 55 (100), 53 (9), 41 (36), 39 (12), 29 (10). Peak 4.MS (EI, Rt 6.67 min., 70 eV): 168 (1, [M]+·), 93 (9), 84 (8), 83 (39), 67 (13), 55 (100), 53 (9), 43 (8), 41 (35), 39 (12), 29 (9).

[0063] ii) 3,7-dimethylnon-6-en-1-ol (IV) Under air atmosphere, 3,7-dimethylnona-2,6-dien-1-ol (IV, 92 g, 0.547 mol, 100% purity) and MeOH (108 g) were added to a 500 mL autoclave vessel followed by Raney Nickel (0.92 g, added in pellet form in one go) and the vessel was sealed. Under stirring (600 rpm), the autoclave was flushed 3 times with N2 (1.8 bar) and then 3 times with H2 (2.0 bar). After adjusting the H2 pressure to 10 bar, the stirring was increased to 1500 rpm while the autoclave was heated to 50 °C. The progress of the reaction was followed and samples were taken. At t = 6h39min, the heating and H2 flow of the autoclave were stopped. After cooling, the pressure was released and the autoclave was flushed 3 times with N2 (1.8 bar). The reaction mixture was filtered to remove the heterogeneous catalyst and the MeOH was removed to give 3,7-dimethylnon-6-en-1-ol (II, 78.6 g, 86.9% purity, 79.8% yield) as a colorless liquid containing two double bond isomers in a 2:1 ratio. 1H-NMR (CDCl3, 400 MHz): δ = 5.14 - 5.03 (m, 2 x 1H, E+Z), 3.74 - 3.60 (m, 2 x 2H, E+Z), 2.09 - 1.89 (m, 2 x 4H, E+Z), 1.67 (q, J=1.2 Hz, 3H, Z), 1.60 (sb, 3H, E), 1.66 -1.13 (m, 2 x 5H, E+Z), 0.98 (t, J=7.5 Hz, 3H, E), 0.96 (t, J=7.5 Hz, 3H, Z), 0.91 (d, J=6.7 Hz, 3H, E), 0.91 (d, J=6.6 Hz, 3H, Z) ppm. 13 C-NMR (CDCl3, 100 MHz): δ = 137.0 (s, Z), 136.7 (s, E), 124.3 (d, Z), 123.1 (d, E), 61.1 (2t, E+Z), 39.8 (2t, E+Z), 37.5 (t, Z), 37.2 (t, E), 32.3 (t, E), 29.2 (2d, E+Z), 25.3 (t, E), 25.0 (t, Z), 24.7 (t, Z), 22.8 (q, Z), 19.5 (2q, E+Z), 15.8 (q, E), 12.8 (q, Z), 12.7 (q, E) ppm. ピーク1.MS (EI, Rt = 6.43 min, 70 eV):170 (3, [M]+·), 123 (39), 95 (18), 83 (18), 81 (42), 71 (18), 70 (19), 69 (21), 67 (26), 55 (100), 41 (45). ピーク2.MS (EI, Rt = 6.43 min, 70 eV):170 (3, [M]+·), 123 (39), 95 (18), 83 (19), 81 (41), 71 (18), 70 (18), 69 (21), 67 (26), 55 (100), 41 (45).

[0064] b) stereoisomer separation 3,7-Dimethylnon-6-en-1-ol (IV) was converted to the corresponding 3,7-dimethylnon-6-en-1-yl 4-nitrobenzoate (VII) to allow separation into the individual isomers by SFC (supercritical fluid chromatography), followed by ester hydrolysis to the individual compounds (R,E)-(IV), (S,E)-(IV), (R,Z)-(IV), and (S,Z)-(IV).

[0065] i) 3,7-Dimethylnon-6-en-1-yl 4-nitrobenzoate (VI): To a stirred solution of compound IV (5 g, 29 mmol, 1 equiv) in DCM (100 mL) at 0° C. was added p-nitrobenzoic acid (2) (7.35 g, 44 mmol, 1.5 equiv), DCC (11.3 g, 55 mmol, 1.9 equiv), and DMAP (1.41 g, 11.6 mmol, 0.4 equiv). It was stirred at room temperature for 16 h. The reaction mixture was filtered and the filtered solid was washed with DCM (50 mL). The filtrate was washed with water (200 mL), dried over sodium sulfate, and concentrated under reduced pressure. The crude product (VII) was purified by HPLC to give 3 (6 g, 64%) as a colorless liquid.

[0066] ii) SFC separation: Compound VII (6 g) was subjected to SFC purification (15% co-solvent: 0.5% isopropylamine in methanol, column: Lux A1 (250 × 30 mm, 5 μ), flow rate: 3 ml / min) to obtain four fractions: (S,E)-(VIIc), (S,Z)-(VIIa), (R,E)-(VIIb), and (R,Z)-(VIId).

[0067] iii) Ester hydrolysis: To a stirred solution of compound (S,Z)-(VII) in THF-MeOH-H2O (7:2:1 vol) at rt was added LiOH.H2O (2 equiv). It was stirred at room temperature for 2 h. The reaction mixture was concentrated under reduced pressure, diluted with water and extracted with EtOAc. The combined organic layers were dried over sodium sulfate and concentrated under reduced pressure. The crude product was purified by flash column chromatography using 6-7% EtOAc in petroleum ether as eluent to give (S,Z)-(V) ((S,Z)-3,7-dimethylnon-6-en-1-ol) as a colorless liquid.

[0068] Compounds (R,E)-(VII), (S,E)-(VII) and (R,Z)-(VII) were therefore hydrolyzed to yield compounds (R,E)-(V) ((R,E)-3,7-dimethylnon-6-en-1-ol), (S,E)-(V) ((S,E)-3,7-dimethylnon-6-en-1-ol) and (R,Z)-(V) ((R,Z)-3,7-dimethylnon-6-en-1-ol). The configurations of the individual isomers were assigned by chiral GC and NMR analysis.

[0069] Example 2: Synthesis of all four isomers of 3,7-dimethylnon-6-enal: General procedure: To a solution of desmartine pedinane (1.2 equiv) in CH2Cl2 (0.02-0.09M) was added dropwise a solution of alcohol V (1.0 equiv) in CH2Cl2 (0.02-0.12M) at 0°C. The reaction mixture was stirred at room temperature for 3 h and quenched with 2M NaOH. The layers were separated and the aqueous layer was extracted with CH2Cl2. The combined organic layers were washed with Na2S2O3, sat. brine, dried over MgSO4 and filtered. The solvent was removed under reduced pressure and the crude was purified by column chromatography (SiO2, Biotage or Pasteur pipette, heptane / MTBE mixtures).

[0070] a) (R,E)-3,7-dimethylnon-6-enal ((R,E)-Ia) obtained from (R,E)-V: (R,E)-3,7-Dimethylnon-6-en-1-ol (50 mg) was oxidized as described in the general procedure to give (R,E)-3,7-dimethylnon-6-enal (10 mg, 20% yield) as a colorless oil. 1 H NMR (600 MHz, C6D6) δ (ppm) = 9.35 (t, J = 1.5 Hz, 1H), 5.11 (t, J = 7.0 Hz, 1H), 2.02 - 1.67 (m, 7H), 1.54 (s, 3H), 1.22 - 1.13 (m, 1H), 1.09 - 1.03 (m, 1H), 0.99 (t, J = 7.5 Hz, 3H), 0.74 (d, J = 6.4 Hz, 3H). 3 C NMR (151 MHz, C6D6) δ (ppm) = 201.2, 137.3, 123.5, 51.3, 37.5, 33.1, 28.1, 26.0, 20.2, 16.3, 13.4.GC-MS (EI) m / z (%):168 (1, [M] +· ), 121 (25), 95 (53), 83 (27), 69 (31), 67 (22), 55 (100), 43 (22), 41 (65), 39 (27), 29 (45). Chiral GC (Sigma-Aldrich, Astec Chiraldex G-DP, 2min@50°C-1°C / min-100°C-5°C / min-2min@200°C): t R / min = 56.67 min. Odor description: Aldehydic, waxy, fatty, floral, rose, citrus, juicy, citronella, watery, pre-cyclised, miraldene, green. GCTH: 0.013ng.

[0071] b) (S,E)-3,7-dimethylnon-6-enal ((S,E)-Ia) obtained from (S,E)-V): (S,E)-3,7-Dimethylnon-6-en-1-ol (0.20 g) was oxidized as described in the general procedure to give (S,E)-3,7-dimethylnon-6-enal (89 mg, 45% yield) as a colorless oil. 1 H NMR and 13 C NMR data are identical to Example 2a. GC-MS (EI) m / z (%): 168 (1, [M]+·), 121 (22), 95 (45), 83 (29), 69 (29), 67 (21), 55 (100), 41 (64), 39 (28), 29 (46), 27 (22). Chiral GC (Sigma-Aldrich, Astec Chiraldex G-DP, 2min@50°C-1°C / min-100°C-5°C / min-2min@200°C): t R / min = 56.45 min. Odor description: Aldehydic, waxy, fatty, green, citrus leaf, citrus, citrus histrix, citronellal, verbena, floral, rose. GCTH: 1.4ng.

[0072] c) (S,Z)-3,7-dimethylnon-6-enal ((S,Z)-Ia) obtained from (S,Z)-V): (S,Z)-3,7-Dimethylnon-6-en-1-ol (25 mg) was oxidized as described in the general procedure to give (S,Z)-3,7-dimethylnon-6-enal (10 mg, 43% yield) as a colorless oil. 1H NMR (600 MHz, C6D6) δ (ppm) = 9.35 (t, J = 2.0 Hz, 1H), 5.06 (t, J = 7.2 Hz, 1H), 2.00 - 1.75 (m, 6H), 1.75 - 1.69 (m, 1H), 1.66 (d, J = 1.1 Hz, 3H), 1.19 - 1.11 (m, 1H), 1.07 - 0.97 (m, 1H), 0.93 (t, J = 7.7 Hz, 3H), 0.73 (d, J = 6.8 Hz, 3H) 13C NMR (151 MHz, C6D6) δ (ppm) = 201.2, 137.5, 124.7, 51.3, 37.8, 28.1, 25.7, 25.4, 23.4, 20.1, 13.4.GC-MS (EI) m / z (%):168 (1, [M]+·), 121 (24), 95 (50), 83 (27), 69 (29), 67 (19), 55 (100), 41 (66), 39 (27), 29 (44), 27 (22). Chiral GC (Sigma-Aldrich, Astec Chiraldex G-DP, 2min@50°C-1°C / min-100°C-5°C / min-2min@200°C): t R / min = 55.38 min. Odor description: Anhydrous, waxy, fatty, green, fatty, metallic, citrus leaf, citrus, juicy, citronellal. GCTH: 0.75ng.

[0073] d) (R,Z)-3,7-dimethylnon-6-enal ((R,Z)-Ia) obtained from (R,Z)-V: (R,Z)-3,7-Dimethylnon-6-en-1-ol (0.20 g) was oxidized as described in the general procedure to give (R,E)-3,7-dimethylnon-6-enal (0.1 g, 56% yield) as a colorless oil. 1 H NMR and 13 C NMR data identical to example 2c. GC-MS (EI) m / z (%): 168 (1, [M]+·), 121 (28), 95 (50), 83 (27), 69 (30), 67 (21), 55 (100), 41 (66), 39 (28), 29 (46), 27 (21). Chiral GC (Sigma-Aldrich, Astec Chiraldex G-DP, 2min@50°C-1°C / min-100°C-5°C / min-2min@200°C): t R / min = 55.54 min. Odor description: Anhydrous, waxy, fatty, green, metallic, fatty, citrus leaf, citrus, juicy, fruity, citronellal. GCTH: 1.2ng.

[0074] Example 3: Synthesis of isomeric aldehyde mixtures Ia, Ib, Ic, II: An autoclave was charged with 3,7-dimethylnona-2,6-dienal (8.0 g, 48.1 mmol, 1.0 equiv, prepared as described in WO2014140032 A1), 5% wet Pd / C (0.20 g, 0.094 mmol, 0.2 mol%, moisture content 58%), and Na2CO3 (0.10 g, 0.94 mmol, 2 mol%). The reaction mixture was then hydrogenated at 3 bar H2 at room temperature for 22 h. The crude was purified by Kugelrohr distillation to give a mixture of aldehydes (6.1 g, 75% yield: 53% of (E)-3,7-dimethylnon-6-enal (E-Ia) + 29% of (Z)-3,7-dimethylnon-6-enal (Z-Ia) + 13% of 3,7-dimethylnon-7-enal (Ib, sum of E / Z isomers) + 1% of 3-methyl-7-methylenenonal (Ic) + 4% of 3,7-dimethylnonal (II)) as a colorless oil. (E)-Ib (olefin signal) 13 C NMR data: 13 C NMR (101 MHz, CDCl3) δ (ppm) = 135.5 (C q ), 118.3 (CH). Characteristic (Z)-Ib (olefin signal) 13 C NMR data: 13 C NMR (101 MHz, CDCl3) δ (ppm) = 135.7 (C q ), 119.0 (CH). Characteristic Ic (olefin signal) 13 C NMR data: 13 C NMR (101 MHz, CDCl3) δ (ppm) = 107.6 (=CH2).

[0075] A reference sample of 3,7-dimethylnonanal (II) was prepared according to literature procedure FR2124279 A1. The analytical data of the mixture of two diastereoisomers were as follows: 13 ℃ NMR (101 MHz, CDCl3) δ (ppm) = 203.1, 51.1, 51.1, 36.9, 34.3, 29.5, 29.4, 28.2, 28.4, 24.4, 20.0, 19.9, 19.2, 19.1, 11.4, 11.4. Aroma description: Fresh citrus metallic (orange, juicy) green. GCTH: 0.19ng.

[0076] Example 4: Synthesis of 2,3,7-trimethylnon-6-en-1-ol IIIa: a) 3,7-Dimethyl-2-methylenenon-6-enal A literature procedure (WO2018024820A1, Example 1) was used to give 3,7-dimethylnon-6-enal (2.50 g, 14.9 mmol, 1.0 equiv, racemic 3,7-dimethylnon-6-en-1-ol prepared according to Example 2 from the E / Z mixture), which was alpha-methylated after Kugelrohr distillation to give 3,7-dimethyl-2-methylenenon-6-enal (1.92 g, 71% yield, mixture of E / Z isomers 57:43). 13 C NMR (101 MHz, CDCl3) δ (ppm) = 194.6, 155.4, 155.4, 137.4, 137.1, 133.0, 123.7, 122.5, 35.9, 35.6, 32.3, 31.0, 31.0, 25.6, 25.3, 24.7, 22.8, 19.5, 19.5, 15.8, 12.8, 12.7. Odor description: Fatty, anhydrous, metallic, fishy, ​​citrus.

[0077] b) 2,3,7-trimethylnon-6-enal 3,7-Dimethyl-2-methylenenon-6-enal (1.80 g, 9.98 mmol, 1.0 equiv) was hydrogenated using a literature procedure (WO2018024820A1, example 2) to give after Kugelrohr distillation 2,3,7-trimethylnon-6-enal (1.50 g, 78% yield, mixture of 4 isomers) as a colorless oil. 13 C NMR (101 MHz, CDCl3) δ (ppm) = 205.7, 205.7, 205.6, 205.6, 137.5, 137.3, 137.3, 123.6, 123.5, 122.4, 122.3, 51.5, 51.5, 50.5, 35.0, 34.7, 33.4, 32.3, 32.3, 32.1, 32.1, 25.4, 24.7, 22.8, 22.8, 17.3, 17.3, 15.9, 15.4, 15.3, 12.8, 12.7, 9.8, 9.8, 8.1, 8.1 Aroma description: Citrus citral, lemongrass, fat, aldehydes. GCTH: 16ng.

[0078] c) 2,3,7-trimethylnon-6-en-1-ol To a solution (4 mL) of NaBH4 (0.10 g, 2.63 mmol, 0.6 equiv) in ethanol was added a solution (4 mL) of 2,3,7-trimethylnon-6-enal (0.80 g, 4.39 mmol, 1.0 equiv) in ethanol at room temperature. After stirring at that temperature for 3 h, the reaction mixture was quenched with water and diluted with MTBE. The layers were separated and the organic layer was washed with sat. NaHCO3 and brine, dried over MgSO4 and concentrated under reduced pressure. The crude was purified by column chromatography and Kugelrohr distillation to give 2,3,7-trimethylnon-6-en-1-ol IIIa (0.48 g, 59% yield, mixture of four isomers in the ratio of 15:24:25:36) as a colorless oil. 1H NMR (400 MHz, CDCl3) δ (ppm) = 5.26 - 4.95 (m, 1H), 3.72 - 3.50 (m, 1H), 3.49 - 3.39 (m, 1H), 2.13 - 1.85 (m, 4H), 1.74 - 1.45 (m, 6H), 1.43 - 1.30 (m, 1H), 1.26 - 1.06 (m, 1H), 0.97 (m, 3H), 0.92 - 0.87 (m, 3H), 0.81 (m, 3H). 13 C NMR (101 MHz, CDCl3) δ (ppm) = 136.9, 124.4, 124.3, 123.2, 123.1, 66.8, 66.0, 66.0, 40.6, 39.5, 35.4, 35.1, 34.1, 33.0, 32.3, 25.7, 24.7, 22.8, 16.9, 16.8, 15.8, 15.8, 14.3, 13.5, 13.5, 12.8, 11.3, 12.8. Odor description: Fat, rose, citronellol, slightly waxy and dusty. GCTH: 0.04ng.

[0079] Example 5: Synthesis of (2-methyl-2-(4-methylhex-3-en-1-yl)cyclopropyl)methanol IIIb: To a solution of diethylzinc (69.5 mL, 69.5 mmol, 1 M hexane, 1.3 equiv) in CHCl (60 mL) was added diiodomethane (10.79 mL, 134 mmol, 2.5 equiv) at −15° C. The reaction mixture was then left to stir at the same temperature for 1 h. To this was added a solution of 3,7-dimethylnona-2,6-dien-1-ol (9 g, 53.5 mmol, 1.0 equiv, prepared according to Rojahn, W. et al. Dragoco Report (German Edition) 1978, 25, 248) in CHCl (50 mL) at −15° C. The reaction mixture was left to stir at room temperature for 20 h. The reaction mixture was quenched at 15° C. by the addition of aqueous ammonium chloride solution (50 mL), diluted with water (50 mL) and filtered through a celite bed. The filtrate was extracted with CHCl (250 mL×2). The combined organic layers were dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give a crude pale yellow liquid, which was purified twice by elution with 4-5% ethyl acetate in petroleum ether on 230-400 size silica gel impregnated with AgNO to give (2-methyl-2-(4-methylhex-3-en-1-yl)cyclopropyl)methanol IIIb (4.7 g, 48% yield, mixture of four isomers in the ratio of 8:25:15:52) as a colorless oil. 1 H NMR (400 MHz, CDCl3) δ (ppm) = 5.18 - 5.02 (m, 1H), 3.78 - 3.42 (m, 2H), 2.16 - 1.92 (m, 4H), 1.71 - 1.59 (m, 3H), 1.44 - 1.30 (m, 2H), 1.22 - 1.11 (m, 1H), 1.11-1.06 (m, 3H), 1.01 - 0.84 (m, 4H), 0.56 - 0.43 (m, 1H), 0.17 - 0.07 (m, 1H). 13C NMR (101 MHz, CDCl3) δ (ppm) = 137.3, 137.0, 136.9, 136.7, 124.2, 122.9, 122.9, 63.9, 63.5, 41.4, 41.1, 34.5, 34.2, 32.3, 27.3, 26.2, 25.6, 25.3, 25.3, 25.0, 24.7, 24.3, 24.3, 22.8, 20.2, 20.2, 19.9, 17.7, 17.6, 17.6, 17.5, 17.0, 17.0, 15.8, 12.8, 12.7. Odor description: Floral, rose, ethyl citronellol, fruity lychee. GCTH: 1.2ng.

[0080] Example 6: Synthesis of 3,7-dimethylnonan-1-ol IIIc: An autoclave was charged with 3,7-dimethylnona-2,6-dienal (2.0 g, 12.0 mmol, 1.0 equiv, prepared as described in WO2014140032 A1), Raney-Ni (0.65 g, washed with ethanol before use), and 20 mL ethanol. The reaction mixture was hydrogenated at 30 bar and 100° C. for 2 h. After filtration and concentration, the crude was purified by chromatography to give 3,7-dimethylnonan-1-ol IIIc (0.97 g, 47% yield, 2 diastereoisomers) as a colorless oil. 1 H NMR (400 MHz, CDCl3) δ (ppm) = 3.77 - 3.59 (m, 2H), 1.67 - 1.50 (m, 2H), 1.44 - 0.97 (m, 11H), 0.94 - 0.80 (m, 9H). 13 C NMR (101 MHz, CDCl3) δ (ppm) = 61.2, 40.0, 40.0, 37.5, 37.4, 36.9, 36.8, 34.4, 29.5, 29.5, 29.5, 29.4, 24.4, 19.4, 11.4, 11.4. Odor description: Floral, rose, peony, fruity, lychee, grape, green, waxy, hot iron. GCTH: 3.1ng.

[0081] Example 7: Synthesis of 4,8-dimethyldec-7-en-2-ol IIId: a) 3,7-dimethylnon-6-enoic acid To a solution of 3,7-dimethylnon-6-en-1-ol (23 g, 135 mmol) in acetone (230 mL) at 0° C., Jones reagent (135 mL) was added over a period of 1 h. The reaction mixture was stirred at 25° C. for 1 h. Acetone was concentrated under reduced pressure, diluted with water (350 mL), and extracted with ethyl acetate (1×700 mL). The organic extract was washed with 5% NaOH solution (1×300 mL). The aqueous layer was acidified to pH=~1-2 with conc. HCl (55 mL). The product was extracted with ethyl acetate (2×600 mL). The combined organic layers were dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by chromatography using 8% ethyl acetate-petroleum ether to give 3,7-dimethylnon-6-enoic acid (8 g, 32%) as a colorless oil.

[0082] b) N-Methoxy-N,3,7-trimethylnon-6-enamide To a suspension of 3,7-dimethylnon-6-enoic acid (15 g, 81 mmol) and N,O-dimethylhydroxylamine hydrochloride (10.3 g, 106 mmol) in CHCl (150 mL) was added EDC*HCl (20.29 g, 106 mmol) and DMAP (15.91 g, 130 mmol) at 25° C. The mixture was stirred at room temperature for 16 h. The reaction mixture was diluted with water (300 mL) and extracted with CHCl (250 mL×2). The combined organic layers were washed with 1.5 N HCl solution (1×150 mL), brine solution (1×150 mL), dried over NaSO, and concentrated under reduced pressure. The crude product was purified by chromatography using 8-10% ethyl acetate and petroleum ether as eluent to give N-methoxy-N,3,7-trimethylnon-6-enamide (15.6 g, 84%) as a colorless liquid.

[0083] c) 4,8-Dimethyldec-7-en-2-one To a stirred solution of N-methoxy-N,3,7-trimethylnon-6-enamide (17 g, 74.8 mmol) in THF (160 mL) was added dropwise methylmagnesium bromide (3.0 M in diethyl ether) (40 mL, 120 mmol) at 0° C. under inert atmosphere. After addition, the reaction mixture was left to stir at 25° C. for 1 h. After completion of the reaction, the reaction mass was quenched with saturated aq. NH4Cl solution (150 mL) at 5° C. and extracted with ethyl acetate (250 mL×2). The combined organic layers were washed with brine solution (1×100 mL), dried over sodium sulfate, and concentrated under reduced pressure. The crude product was purified by chromatography eluting with 4-6% ethyl acetate in petroleum ether to give 4,8-dimethyldec-7-en-2-one (11.5 g, 84%) as a colorless liquid. Odor description: Fatty (soapy) fruity citrus.

[0084] d) 4,8-Dimethyldec-7-en-2-ol To a stirred solution of 4,8-dimethyldec-7-en-2-one (6.4 g, 35.1 mmol) in methanol (65 mL) was added NaBH4 (0.664 g, 17.5 mmol) portionwise at 0° C. The reaction mixture was stirred at room temperature for 1.5 h. The reaction mixture was cooled to 0° C., quenched with ice water (40 mL), and extracted with ethyl acetate (2×150 mL). The combined organic layers were washed with brine (1×60 mL), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by chromatography using 7-8% ethyl acetate & petroleum ether as eluent to give 4,8-dimethyldec-7-en-2-ol (5.25 g, 81%, mixture of four isomers in the ratio 8:28:60:4) as a colorless oil. 13C NMR (101 MHz, CDCl3, 2 major isomers) δ (ppm) = 124.3, 124.3, 123.1, 66.2, 65.8, 46.9, 46.8, 38.0, 37.7, 37.3, 37.0, 32.3, 29.5, 29.5, 29.1, 25.3, 25.2, 25.0, 24.7, 24.3, 24.3, 23.6, 23.6, 22.9, 20.1, 19.3, 19.3, 15.8, 12.8, 12.8. Odor description: floral, rose, peony, pomerol, green, grapefruit, waxy, fatty, slightly stearic. GCTH: 15ng.

[0085] Example 8: Biodegradation results of compound Ia (mixture of four stereoisomers) The manometric respirometry test (OECD Guideline No. 301F, Paris 1992) was used to assess the biodegradability of a) compound Ia (mixture of four stereoisomers) and b) the mixture of Example 3 (aldehyde mixture Ia, Ib, Ic, II).

[0086] The results are: a) Compound Ia (a mixture of four stereoisomers) exhibits a BOD (biological oxygen demand) of 70% (60 days, readily biodegradable) (Figure 1), and b) The mixture of Example 3 (aldehyde mixtures Ia, Ib, Ic, II) showed a BOD (biological oxygen demand) of 87% (readily biodegradable over 60 days) (Figure 2).

[0087] A compound can be classified as biodegradable if it reaches a passing level of 60% of the theoretical oxygen consumption required for complete mineralization. If a passing level is achieved within 10 days of the 28-day test period, it is readily biodegradable. The 10-day window begins when 10% biodegradation is reached. If passing levels are obtained after the 28 day test period, the compound can be classified as inherently biodegradable.

[0088] Example 9: Perfume The base Accord REF has been modified by the addition of different compounds according to the invention and comparison compounds as outlined in Table 1. [Table 1]

[0089] REF: This accord presents fresh citrus grapefruit top note characteristics with floral rose musk base notes. It is intended for use in shampoos or shower gels. The application is in shampoos at 0.8%. The addition of 0.3% of a mixture of the four isomers of A:Ia brings to the already fresh, aldehydic, vibrant facets as well as citrus juicy facets that reinforce the natural attributes as well as the perceived effectiveness olfactory cues.

[0090] B: In comparison, the addition of 1% citronellal also provides some juiciness, but tends to impart a citronella olfactory cue that is not typically appreciated by consumers, especially in the Western world. C: The addition of 3% citronellal gives a distinct citronella character, making it even more appealing for consumer preference.

[0091] D: The addition of 0.3% of the isomeric aldehyde mixture of Example 3 results in green, bright, metallic, and citrus, lemongrass effects, which also enhance the naturalness and sensory effects due to a contribution to the olfactory activity that is clearly different from the mixture of the four isomers of Ia. E: The addition of 6% compound of Example 4 (IIIa) brings a soft floral rose depth to the accord and enhances the olfactory aspects of juicy citrus and the hedonic aspect of naturalness of the care. F: The combination of a mixture of 0.3% of the four isomers of Ia and 6% of the compound of Example 4 (IIIa) combines both a lively naturalness for the lift and top notes, and a juicy aspect of care for the hedonic and underwater blooms.

Claims

1. (R,E)-3,7-dimethylnon-6-enal, formula (R,E)-(Ia) 【Chemical 1】 A compound represented by the formula:

2. The compound represented by formula (R,E)-(Ia) according to claim 1 and the compounds represented by formula (S,E)-(Ia), formula (R,Z)-(Ia) and formula (S,Z)-(Ia) 【Chemistry 2】 and at least one other compound selected from the group consisting of compounds represented by

3. Use of the compound represented by formula (R,E)-(Ia) according to claim 1 or the isomer mixture according to claim 2 as a fragrance ingredient.

4. A compound represented by the formula (R,E)-(Ia), which is (R,E)-3,7-dimethylnon-6-enal. 【Chemistry 3】 or a compound represented by A compound represented by formula (R,E)-(Ia), a compound represented by formula (S,E)-(Ia), a compound represented by formula (R,Z)-(Ia) and a compound represented by formula (S,Z)-(Ia) 【Chemistry 4】 and at least one other compound selected from the group consisting of compounds represented by A fragrance composition comprising:

5. Formulas (Ib), (Ic) and (II) 【Chemistry 5】 wherein the wavy bond indicates an unspecified configuration of the adjacent double bond, and the star indicates the stereocenter of the C atom. The fragrance composition according to claim 4, further comprising at least one compound selected from the group consisting of compounds represented by the formula:

6. Formula (III) 【Chemistry 6】 During the ceremony, 【Chemistry 7】 indicates a carbon-carbon single or double bond, A wavy bond, when present, indicates an unspecified configuration of the adjacent double bond; and R １ , R ２ and R ３ is independently selected from H or Me; Alternatively, in the formula, R １ is H or Me, and R ２ and R ３ form a cyclopropyl ring together with the carbon atom to which they are attached, The fragrance composition of claim 4, further comprising at least one compound represented by the formula:

7. At least one of the compounds represented by formula (III) is selected from the group consisting of formulas (IIIa), (IIIb), (IIIc), and (IIId): 【Chemistry 8】 wherein the wavy bond, when present, indicates an unspecified configuration of the adjacent double bond. The fragrance composition according to claim 6, wherein the compound is selected from the group consisting of compounds represented by the formula:

8. Formula (III) 【Chemistry 9】 During the ceremony, 【Chemistry 10】 indicates a carbon-carbon single or double bond, and wavy bonds, when present, indicate any arrangement of adjacent double bonds; and R １ , R ２ and R ３ is independently selected from H or Me; Alternatively, in the formula, R １ is H or Me, and R ２ and R ３ form a cyclopropyl ring together with the carbon atom to which they are attached, A compound represented by However, the compound is not 3,7-dimethylnonan-1-ol.

9. Formulas (IIIa), (IIIb), and (IIId) 【Chemistry 11】 wherein the wavy bond, when present, indicates an unspecified configuration of the adjacent double bond.

9. The compound of claim 8 selected from the group consisting of compounds represented by:

10. A fragrance composition comprising at least one compound represented by formula (III) according to claim 8.

11. At least one compound of formula (X) 【Chemistry 12】 During the ceremony, 【Chemistry 13】 indicates a carbon-carbon single or double bond, where, if present, the wavy bond indicates an unspecified configuration of the adjacent double bond, and the star indicates the stereocenter of the C atom. The fragrance composition according to claim 4, further comprising a compound represented by the formula:

12. A consumer product comprising a compound represented by formula (R,E)-(Ia) according to claim 1, or an isomer mixture according to claim 2, or a fragrance composition according to claims 4 to 7 or 11, and a consumer product base.

13. A consumer product comprising a compound of formula (III) according to claim 8 or a fragrance composition according to claim 10, and a consumer product base.

14. 13. The consumer product of claim 12, wherein the consumer product base is selected from fine fragrances, household products, laundry products, body care products, cosmetic products, and air care products.

15. 10. A method of improving, imparting, enhancing or modifying a consumer product base by means of the addition thereto of an olfactorily acceptable amount of a compound of formula (R,E)-(Ia) as defined in claim 1, or an isomeric mixture as defined in claim 2, or a fragrance composition as defined in claims 4 to 7 or 11, or a compound of formula (III) as defined in claim 7, or a fragrance composition as defined in claim 8.

Images