Fragrance composition comprising dihydrolevoglucosenone derivatives

Abstract

A fragrance composition comprising one or more compounds having a general Formula I wherein R is selected from the group consisting of methyl and allyl, and uses of these compounds for preparing a fragrance composition, a pharmaceutical composition, a cosmetic composition, and / or a cleaning composition.

Description

FIELD OF THE INVENTION

[0001] The present invention relates generally to olfactive compounds, more specifically dihydrolevoglucosenone derivatives having olfactive properties.BACKGROUND OF THE INVENTION

[0002] To increase the range of notes available to perfumers and flavorists in their creations, the perfume and flavor industry is constantly looking for new organoleptic compounds to meet increasing regulatory requirements, such as replacing compounds identified by regulatory bodies as undesirable (or unacceptable) or replacing compounds having stability problems. Additionally, cost constraints are increasingly important.

[0003] For example, vanillin (4-hydroxy-3-methoxybenzaldehyde) or other vanilla smelling compounds or compositions typically contain phenol functional groups and often lead to coloration issues. Natural vanilla extracts are expensive and comprise a complex mixture of fragrant compounds, many of which also contain phenol groups, and are thus colored themselves or prone to coloration issues.

[0004] Accordingly, in order to meet the constant needs of the perfume and flavor industry, and to expand the available palette of perfumers and flavorists, there is a need for new compounds having vanillin fragrance, bouquet, and / or note.

[0005] Tsypysheva et al. (Russian Chemical Bulletin, Intl. Ed., Vol. 49, no. 7, July 2002, pp 1237-1239) described stereochemical differentiation in reactions of organometallic reagents with levoglucosenone and some of its dihydro derivatives, specifically disclosing (1S,5R)-4-methyl-6,8-dioxabicyclo[3.2.1]octan-4-ol. However, (1S,5R)-4-methyl-6,8-dioxabicyclo[3.2.1]octan-4-ol has not been described and characterized as a compound that is useful in fragrance applications. This application describes the surprising and unexpected olfactive qualities of dihydrolevoglucosenone derivatives and their uses as a readily accessible and cost-effective fragrance ingredient, and potential applications thereof.SUMMARY OF THE INVENTION

[0006] Certain aspects of the present disclosure are described in the appended claims. There are additional features and advantages of the subject matter described herein. They will become apparent as this specification proceeds. The various features described in the claims and below for various embodiments may be used in combination or separately. For example, specified ranges may be inclusive of their recited endpoints, unless explicitly excluded. Any particular embodiment need not provide all features noted above, nor solve all problems or address all issues noted above.

[0007] According to embodiments of the present invention, a fragrance composition is provided, comprising (or consisting essentially of, or consisting of): one or more compounds derived from dihydrolevoglucosenone, which have a general Formula I wherein R is selected from the group consisting of methyl and allyl (propyl-2-en-1-yl).

[0008] According to embodiments of the present invention, use of one or more compounds having a general Formula I as fragrant agent(s) / compound(s) (in particular for its / their pleasant fragrance properties (such as vanillin profiles)) is provided.

[0009] According to embodiments of the present invention, use of one or more compounds having a general Formula I for preparing a fragrance composition, a pharmaceutical composition, a cosmetic composition, or a cleaning composition is also provided.

[0010] According to embodiments of the present invention, use of one or more compounds having a general Formula I for conferring, modifying, improving or enhancing fragrant properties to a fragrance composition (for example to a perfume composition), a pharmaceutical composition, a cosmetic composition, or a cleaning composition is also provided.DETAILED DESCRIPTION

[0011] Unless otherwise explained, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In case of conflict, the present specification, including explanations of terms, will control. The singular terms "a," "an," "at least one," and "the" include plural referents unless context clearly indicates otherwise. Similarly, the word "or" is intended to include "and" unless the context clearly indicates otherwise. The term "comprising" means "including;" hence, "comprising A or B" means including A or B, as well as A and B together.

[0012] Embodiments of the invention relate to compounds derived from dihydrolevoglucosenone ((1R,5S)-7,8-dioxabicyclo[3.2.1]octan-2-one; CAS No. 53716-82-8), said compounds having pleasant fragrance properties (such as vanillin profiles), their preparation process, as well as their uses in the chemical industry, and in particular in perfumery, parapharmacy, cosmetics, detergents, etc., said compounds having interesting olfactive properties and a particular potency, persistence, and color stability.

[0013] Thus, in accordance with an embodiment of the invention, a fragrance composition is provided, comprising one or more compounds derived from dihydrolevoglucosenone. The dihydrolevoglucosenone derivatives have a general Formula I wherein R is selected from the group consisting of methyl and allyl (propyl-2-en-1-yl). In an embodiment, R is a methyl providing (1S,5R)-4-methyl-6,8-dioxabicyclo[3.2.1]octan-4-ol. In another embodiment, R is an allyl (propyl-2-en-1-yl) providing (1S,5R)-4-allyl-6,8-dioxabicyclo[3.2.1]octan-4-ol.

[0014] Dihydrolevoglucosenone is obtained by the hydrogenation of levoglucosenone ((1S,5R)-6,8-dioxabicyclo[3.2.1]oct-2-en-4-one; CAS No. 37112-31-5), which itself is obtained by the acid-catalyzed pyrolysis of lignocellulosic biomass such as sawdust. Levoglucosenone is a chiral compound, and thus the creation of asymmetric centers in the structure of the compounds of Formula I according to the invention causes the existence of several diastereomeric forms. The invention also covers the compounds represented by the general Formula I in the form of mixtures of diastereomers, in varying proportions. The invention also envisages compounds of Formula I in the form of a single diastereomer. Diastereomer pure forms may be obtained by chromatographic separation methods, for example.

[0015] As used herein, the term "fragrance composition" means a mixture of dihydrolevoglucosenone derivatives having the general Formula I, and one or more fragrance ingredients, including one or more auxiliary substances, if desired. The one or more fragrance ingredients include, but are not limited to, odorous compositions and odorous chemical compounds. The auxiliary substances include, but are not limited to, solvents (volatile and non-volatile), fixatives, and adjuvants.

[0016] The effective amount of the compounds of general Formula I incorporated into fragrance compositions depends on the nature of said compositions, the desired odorous effect, and the nature of other odorous compounds possibly present. It can vary in a very wide range, from 100 ppb to 99 wt%, based on the total weight of the composition. For example, in an embodiment, the compound(s) of general Formula I may be incorporated into a composition in an amount from 100 ppb to 99 wt%, or from 0.0001 wt% to 50 wt%, in particular 0.01 wt% to 30 wt%. The preceding percentages are expressed by weight relative to the total weight of the composition.

[0017] Examples of products having fragrance compositions include, but are not limited to, perfumes, soaps, insect repellents and insecticides, detergents, household cleaning agents, air fresheners, room sprays, pomanders, candles, cosmetics, toilet waters, pre- and aftershave lotions, talcum powders, hair care products, body deodorants, anti-perspirants, and pet litter.

[0018] In an embodiment, the fragrance ingredient(s) used in combination with the compounds of the present invention may comprise odorous compositions, including natural products such as extracts, essential oils, absolutes, resinoids, resins, concretes etc., but also synthetic products. The fragrance ingredient may include odorous chemical compounds such as hydrocarbons, alcohols, aldehydes, ketones, ethers, acids, esters, acetals, nitriles etc., including saturated or unsaturated, aliphatic, heterocyclic, or carbocyclic compounds. Such odorous chemical compounds are mentioned, for example, in S. Arctander, "Perfume and Flavor Chemicals" (Montclair, N.J., 1969), or in "Common Fragrance and Flavor Materials", Wiley-VCH, Weinheim, 2006. Finally, a plurality of compounds of general Formula (I) can also be used in combination in the same composition.

[0019] In an embodiment, the auxiliary substance(s) used in combination with the compounds of the present invention may comprise a solvent, which may include volatile solvents or non-volatile solvents. As used herein, "volatile" refers to substances with a significant amount of vapor pressure under ambient conditions, as is understood by those in the art. The volatile solvents for use herein will preferably have a vapor pressure of about 2kPa or more, more preferably about 6kPa or more at 25°C. The volatile solvents for use herein will preferably have a boiling point under 1 atm, of less than about 150°C, more preferably less than about 100°C, even more preferably less than about 90°C, even more preferably still less than about 80°C.

[0020] Preferably the volatile solvents for use herein will be safe for use on a wide range of substrates, more preferably on human or animal skin or hair. Suitable volatile solvents include, but are not limited to, those found in the CTFA International Cosmetic Ingredient Dictionary and Handbook, 7th edition, volume 2 PI 670 - 1672, edited by Wenninger and McEwen (The Cosmetic, Toiletry, and Fragrance Association, Inc., Washington, D. C, 1997). Suitable volatile solvents do not include tetrahydrofuran or diethyl ether.

[0021] Non-limiting examples of some alcohol volatile solvents include ethanol or other alcohols (e.g., methanol, propanol, isopropanol, butanol, and mixtures thereof). Non-limiting examples of non-volatile solvents include benzyl benzoate, diethyl phthalate, isopropyl myristate, propylene glycol, dipropylene glycol, triethyl citrate, and mixtures thereof.

[0022] A fixative is a base ingredient or blend that is utilized in fragrance compositions to help the scent last longer. For example, fixatives can reduce the rate of evaporation of the more volatile materials in the fragrance composition. A non-limiting list of fixatives includes resinoids such as benzoin, labdanum, myrrh, olibanum, storax, and tolu balsam; terpenoids such as ambroxide ((3aR,5aS,9aS,9bR)-3a,6,6,9a-tetramethyldodecahydronaphtho[2,1-b]furan); polycyclic ketones such as civetone ((9Z)-cycloheptadec-9-en-1-one) and muscone ((3R)-3-methylcyclopentadecan-1-one); glycerin; Galaxolide (4,6,6,7,8,8-hexamethyl-1,3,4,6,7,8-hexahydrocyclopenta[g]isochromene); Iso E Super (1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8,-tetramethyl-2-naphthyl)ethan-1-one); Orrisroot (Rhizoma iridis); benzyl benzoate; triethyl citrate; dipropylene glycol (DPG); ethyl hexyl glycerin; and Oud base.

[0023] In an embodiment, the auxiliary substance(s) used in combination with the compounds of the present invention may be an adjuvant. The term "adjuvant" refers to ingredients that might be employed in a fragrance composition for reasons not specifically related to the olfactive performance of said composition. For example, an adjuvant may be an ingredient that acts as an aid to processing a fragrance ingredient or ingredients, or a composition containing said ingredient(s), or it may improve handling or storage of a fragrance ingredient or composition containing same. It might also be an ingredient that provides additional benefits such as imparting color or texture. It might also be an ingredient that imparts light resistance or chemical stability to one or more ingredients contained in a fragrance ingredient or composition containing same. A detailed description of the nature and type of adjuvants commonly used in fragrance compositions containing same cannot be exhaustive, but it has to be mentioned that said ingredients are well known to a person skilled in the art. Examples of adjuvants include surfactants and emulsifiers; viscosity and rheology modifiers; thickening and gelling agents; preservative materials; pigments, dyestuffs and coloring matters; extenders, fillers and reinforcing agents; stabilizers against the detrimental effects of heat and light, bulking agents, acidulants, buffering agents, and antioxidants.

[0024] Because of the pleasant smell (vanillin fragrance, bouquet, and / or note), the compounds of general Formula I find many applications in perfumery. The term "perfumery" is used here in its general sense; it refers not only to traditional perfumery (alcoholic or not), but also to other areas in which the smell / fragrance of products is important. Reference may thus be made to perfumery compositions in the usual and traditional sense (such as perfume bases and concentrates, perfumes, colognes, eau de toilette, indoor air fresheners, home fragrances, scented candles and similar products), to topical compositions including cosmetic compositions (such as face and / or body creams, talcum powders, hair oils, shampoos, hair lotions, bath salts and oils, shower and / or bath gels, toilet soaps, antiperspirants and body deodorants, shaving lotions and creams, soaps, toothpastes, mouthwashes, ointments, and similar products), as well as cleaning products, in particular household cleaning products (such as detergents, detergents, fabric softeners, home air fresheners, home fragrances and similar products).

[0025] Thus, embodiments of the invention extend to a perfume composition comprising at least one compound of general Formula I. It may, in particular, be a composition of the traditional perfumery, a cosmetic composition, cleaning product, or a so-called "intermediate composition", which is intended to be used for the preparation of compositions or finished products (including perfumes, cosmetics, cleaning products).

[0026] Such a perfume composition is generally prepared from a basic product, in which the compound or compounds of the invention are found to be incorporated. The basic product will be easily determined by those skilled in the art according to the composition envisaged and therefore the intended use. The composition of these basic products and the nature of their usual components, such as perfuming ingredient(s), solvent(s), and / or adjuvant (s), are well known to those skilled in the art.

[0027] The compounds used in these perfume compositions, in particular the compounds of the invention, may be incorporated into or on an inert support material. The carrier materials that can be used are many and varied, for example polar solvents, oils, greases, finely divided solids, cyclodextrins, maltodextrins, gums, resins, and any other carrier material known for such compositions (for example, soaps, candles, ointments, textiles, wipes, scented gels, or the like).

[0028] In accordance with yet another embodiment of the invention, the use of at least one compound of general Formula I, in a form of a stereoisomer or a mixture of stereoisomers, to confer, modify, or enhance the olfactive or visual properties of a substance, a composition, or an article is provided.

[0029] The present invention also relates to a process for modifying the olfactive or visual properties of a substance, a composition, or an article comprising at least one of the following steps: adding a compound of general Formula I to said substance, composition, or article, or applying a compound of general Formula I to the surface of said article.

[0030] The compounds according to the invention may particularly be used as a masking agent or as an odor neutralizing agent. As used herein, the term "masking agent" or "odor neutralizing agent" is meant to identify a characteristic of the compounds within the scope of the invention to reduce or eliminate the perception of a bad odor generated by one or more other molecules present in a composition or a product.

[0031] As noted above, the compounds of general Formula I may be synthesized from dihydrolevoglucosenone. In 2006, the Australian company CIRCA Group AS established their proprietary Furacell ™< technology to manufacture levoglucosenone from cellulosic waste. CIRCA launched a saturated version of levoglucosenone (dihydrolevoglucosenone; tradename Cyrene ™< ), which is promoted as a new "green" solvent substituting dimethylformamide (DMF).

[0032] A variety of dihydrolevoglucosenone derivatives were prepared by the 1,2-addition of various alkyl Grignard reagents (as shown in Scheme 1 below). Accordingly, the resulting tertiary alcohol products (i.e., methyl, ethyl, propyl, butyl, but-2-ene-3-yl, and allyl) were isolated, purified, and tested.

[0033] Interestingly, the methyl derivative (Compound 3A) unexpectedly provides a vanilla, smoky, phenolic fragrance profile, and the allyl derivative (Compound 3B) unexpectedly provides vanilla, smoky, grilled, bacon profile. This is particularly surprising given that, in contrast, the ethyl derivative (Compound 3C) was almost odorless with slight bacon notes; the propyl derivative (Compound 3D) has a very weak smell of candy necklace; the butyl derivative (Compound 3E) is very weak, slightly tutti-fruity note; and the (E)-But-2-en-2-yl derivative (Compound 3F) has a very weak unpleasant smell of a dirty mop.

[0034] As indicated above, vanillin or other vanilla smelling compounds typically contain phenols and often lead to coloration issues. The new fragrance compounds (3A and 3B) do not comprise a phenol moiety and demonstrate good stability in different fragrance applications and, in particular, no visual coloration issues (e.g., darkening) were observed over several months.EXAMPLES

[0035] Compound 3A: (1S,5R)-4-methyl-6,8-dioxabicyclo[3.2.1]octan-4-ol: In a three necked round bottomed flask under N 2 at 0 °C are added Cyrene ™< (50 g, 390 mmol) and cyclopentyl methyl ether (CpOMe) (50 ml). Methylmagnesium chloride 3M (156 ml, 468 mmol) is added dropwise so that the temperature remained below 15 °C. The mixture is stirred 1 h at room temperature. The mixture is poured into a solution of ice (50 g), water (50 mL) and sat. NH 4 Cl aq . (50 mL). Water (50 mL) and ethyl acetate (150 mL) are added.(50 mL). The aqueous phase is extracted with ethyl acetate (2 x 150 mL). The combined organic phases are gathered and concentrated on rotavapor. PG2000 (10% w / w of the concentrate) is added and the mixture distilled under vacuum (43 to 53 °C, 1 mbar). (1S,5R)-4-methyl-6,8-dioxabicyclo[3.2.1]octan-4-ol (37.95 g, 67%) is recovered as a mixture of isomers (34 / 66) in the form of a colorless to yellowish liquid.

[0036] MS (EI +< ) Major: 98 (10), 58 (52), 55 (11), 43 (100), 41 (23); Minor: 98 (11), 58 (53), 55 (12), 43 (100), 41 (24).

[0037] 1< H NMR (300 MHz, CDCl 3 ) : δ 4.94 (s, 1H), 4.62 - 4.29 (m, 1H), 3.86 - 3.71 (m, 2H), 2.45 (s, 1H), 2.01 - 1.39 (m, 4H), 1.18 (s, 3H).

[0038] 13< C NMR (75 MHz, CDCl 3 ) : δ 106.02, 73.24, 70.53, 67.50, 32.06, 27.35, 21.84. IR (cm -1< ) : 3452 (OH). Odor: Vanilla, phenolic, spicy, smoky; Odor threshold: 15.40 ng / L; GC-O analysis: minor isomer is much more vanillin like, smoky whereas the major isomer is almost odorless. Taste at 20 ppm in water: smoky, creamy, slightly woody.

[0039] Compound 3B: (1S,5R)-4-allyl-6,8-dioxabicyclo[3.2.1]octan-4-ol: In a three necked round bottomed flask under N 2 at 0 °C are added Cyrene ™< (20 g, 156 mmol, 1 eq.) and THF (200 ml). Allylmagnesium chloride 2M in THF (94 ml, 187 mmol, 1.2 eq.) is added dropwise so that the temperature remained below 15 °C. The mixture is stirred 15 min at room temperature. The mixture is poured into a solution of ice (50 g), ethyl acetate (300 mL) and sat. NH 4 Cl aq . (100 mL). The aqueous phase is extracted with ethyl acetate (2 x 150 mL). The combined organic phases are gathered, washed with brine (100 mL) and concentrated on rotavapor. The concentrate is distilled under vacuum (66 °C, 0.3 mbar). (1S,5R)-4-allyl-6,8-dioxabicyclo[3.2.1]octan-4-ol (19 g, 70.9%) is recovered as a mixture of isomers (26 / 74) in the form of colorless liquid.

[0040] MS (EI +< ) Major: 124 (4), 84 (17), 83 (100), 69 (10), 57 (11), 56 (30), 55 (67), 43 (27), 42 (24), 41 (46), 39 (22); Minor: 170 (1), 124 (3),84 (18), 83 (100), 69 (10), 57 (10), 56 (31), 55 (71), 43 (28), 42 (24), 41 (45), 39 (22).

[0041] 1< H NMR (300 MHz, CDCl 3 ) : 6.02 - 5.80 (m, 1H), 5.21 - 5.08 (m, 2H), 5.14 - 5.01 (m, 1H), 4.52 (dqd, J = 5.6, 2.9, 1.3 Hz, 1H), 3.87 (dd, J = 7.2, 1.0 Hz, 1H), 3.80 (ddd, J = 7.0, 4.9, 1.4 Hz, 1H), 2.30 (dddt, J = 39.2, 7.5, 2.7, 1.2 Hz, 2H), 2.13 - 1.85 (m, 1H), 1.91 - 1.80 (m, 1H), 1.85 - 1.40 (m, 2H).

[0042] 13< C NMR (75 MHz, CDCl 3 ) : δ 133.02, 118.57 (d, J = 9.9 Hz), 105.02, 73.25, 71.79, 67.75, 39.11, 29.66, 27.04.

[0043] IR (cm -1< ) : 3465(OH), 1125 (C-O), 892(=CH). Odor: vanilla, smoky, grilled, bacon; Taste at 5 ppm in water: Vanilla nuances, almond.

[0044] Comparative Compound 3C: (1S,5R)-4-ethyl-6,8-dioxabicyclo[3.2.1]octan-4-ol. In a three necked round bottomed flask under N 2 at 0 °C are added Cyrene ™< (10 g, 78 mmol, 1 eq.) and CpOMe (150 ml). Ethylmagnesium chloride 2M in THF (51 ml, 102 mmol, 1.3 eq.) is added dropwise so that the temperature remained below 15 °C. The mixture is stirred 1 week at room temperature. The mixture is poured into a solution of ice (50 g), water (50 mL) and sat. NH 4 Cl aq . (50 mL). The aqueous phase is extracted with ethyl acetate (3 x 150 mL). The combined organic phases are gathered and concentrated on rotavapor. The concentrate is distilled under vacuum (50-53 °C, 0.3 mbar). (1S,5R)-4-ethyl-6,8-dioxabicyclo[3.2.1]octan-4-ol (3.6 g, 26%) is recovered as a mixture of isomers (38 / 62) in the form of colorless liquid having a purity of 90%. GC-O analysis revealed the compound to be almost odorless with slight bacon notes.

[0045] MS (EI +< ) Major: 112 (14), 83 (21), 72 (33), 57 (100), 55 (41), 53 (12), 44 (14), 43 (69), 41 (28), 39 (22); Minor: 83 (16), 72 (33), 57 (100), 55 (36), 43 (50), 42 (12), 41 (29), 39 (27).

[0046] 1< H NMR (300 MHz, CDCl 3 ) : 5.10 - 5.00 (m, 1H), 4.51 (qd, J = 2.8, 1.4 Hz, 1H), 3.94 - 3.74 (m, 2H), 2.12 - 1.75 (m, 2H), 1.75 - 1.38 (m, 4H), 0.95 (q, J = 7.6 Hz, 3H).

[0047] 13< C NMR (75 MHz, CDCl 3 ) : δ 105.14, 104.59, 73.30, 73.00, 72.05, 71.41, 67.65, 67.16, 29.70, 29.66, 27.23, 27.19, 27.02, 25.58, 7.08, 6.37.

[0048] IR (cm -1< ) : 3461(OH), 2889+2942(CH2), 1127(C-O); Odor (mixture): Slightly smoky / bacon.

[0049] Comparative Compound 3D: (1S,5R)-4-propyl-6,8-dioxabicyclo[3.2.1]octan-4-ol: In a three necked round bottomed flask under N 2 at 0 °C are added Cyrene ™< (10 g, 78 mmol, 1 eq.) and CpOMe (150 ml). n-Propylmagnesium chloride 1M in THF (94 ml, 94 mmol, 1.2 eq.) and propylmagnesium chloride 2M in THF (13 ml, 26 mmol, 0.3 eq.) are added dropwise so that the temperature remained below 15 °C. The mixture is stirred overnight at room temperature. The mixture is then poured into a solution of ice (50 g), water (50 mL) and sat. NH 4 Cl aq . (50 mL). The aqueous phase is extracted with ethyl acetate (3 x 150 mL). The combined organic phases are gathered and concentrated on rotavapor. The concentrate is distilled under vacuum (54 °C, 0,7 mbar). (1S,5R)-4-propyl-6,8-dioxabicyclo[3.2.1]octan-4-ol (3.4 g, 19%) is recovered as a mixture of isomers (41 / 59) in the form of colorless liquid with an overall GC purity of 73%. GC-O analysis of the mixture showed that the isomers have a very weak smell of candy necklace.

[0050] MS (EI +< ) Major : 86 (17), 83 (21), 71 (67), 58 (100), 57 (18), 55 (33), 53 (10), 43 (63), 41 (35), 39 (22); Minor: 86 (13), 83 (25), 71 (63), 58 (100), 57 (12), 55 (31), 53 (10), 43 (62), 42 (10), 41 (29), 39 (21).

[0051] 1< H NMR (300 MHz, CDCl 3 ) : 5.32 (d, J = 1.5 Hz, 0H), 5.14 - 4.98 (m, 1H), 4.49 (ddq, J = 4.5, 3.0, 1.6 Hz, 1H), 3.92 - 3.73 (m, 3H), 3.60 (ddd, J = 9.8, 6.0, 1.8 Hz, 0H), 2.11 - 1.95 (m, 1H), 1.95 - 1.75 (m, 1H), 1.80 - 1.61 (m, 0H), 1.66 - 1.57 (m, 0H), 1.61 - 1.52 (m, 1H), 1.57 - 1.32 (m, 4H), 0.98 - 0.84 (m, 2H).

[0052] 13< C NMR (75 MHz, CDCl 3 ) : δ 105.15, 104.71, 102.93, 73.29, 73.00, 72.79, 72.12, 71.46, 69.01, 68.18, 67.69, 67.15, 39.43, 36.87, 30.27, 27.84, 27.58, 27.26, 26.14, 25.58, 16.02, 15.29, 14.72, 14.64.

[0053] IR (cm -1< ) : 3451(OH), 2953+2892(CH3), 1128 (C-O). Isomers have a very weak smell of candy necklace.

[0054] Comparative Compound 3E: (1S,5R)-4-butyl-6,8-dioxabicyclo[3.2.1]octan-4-ol: In a three necked round bottomed flask under N2 at 0 °C are added Cyrene (10 g, 78 mmol, 1 eq.) and CpOMe (150 ml). n-Butylmagnesium chloride 2M in THF (78 ml, 156 mmol, 2 eq.) is added dropwise so that the temperature remained below 15 °C. The mixture is stirred overnight at room temperature. The mixture is then poured into a solution of ice (50 g), water (50 mL) and sat. NH 4 Cl aq . (50 mL). The aqueous phase is extracted with ethyl acetate (3 x 50 mL). The combined organic phases are gathered and concentrated on rotavapor. The concentrate is distilled under vacuum (73 °C, 0.3 mbar). (1S,5R)-4-butyl-6,8-dioxabicyclo[3.2.1]octan-4-ol (6.8 g, 44%) is recovered as a mixture of isomers (41 / 59) in the form of colorless liquid. MS (EI +< ) Major: 98 (13), 85 (59), 83 (21), 71 (14), 58 (100), 57 (39), 55 (42), 53 (11), 43 (41), 41 (45), 39 (18); Minor: 98 (17), 85 (81), 83 (21), 71 (14), 58 (100), 57 (46), 55 (42), 43 (42), 42 (15), 41 (57), 39 (21).

[0055] 1< H NMR (300 MHz, CDCl 3 ): 4.33 (dt, J = 9.3, 3.9 Hz, 1H), 3.12 (dq, J = 17.2, 5.7 Hz, 2H), 1.42 - 1.24 (m, 2H), 1.19 - 1.08 (m, 1H), 0.97 - 0.76 (m, 2H), 0.80 (s, 1H), 0.75 - 0.52 (m, 5H), 0.20 (dh, J = 7.3, 3.7 Hz, 3H).

[0056] 13< C NMR (75 MHz, CDCl 3 ): δ 105.34, 104.88, 77.58, 76.74, 76.41, 73.41, 73.12, 72.20, 71.54, 69.12, 67.81, 67.28, 37.02, 34.41, 30.36, 27.97, 27.72, 27.38, 25.72, 25.01, 24.24, 23.48, 23.38, 14.19.

[0057] IR (cm -1< ) : 3467(OH), 2951+2870(CH3), 1127(C-O); Odor (mixture): very weak, slightly smoky; GC-O analysis: major compounds are very weak, slightly tutti-fruity. Smoky note comes from impurities.

[0058] Comparative Compound 3F: (1S,5R)-4-((E)-but-2-en-2-yl)-6,8-dioxabicyclo[3.2.1]octan-4-ol: In a three necked round bottomed flask under N 2 at 0 °C are added Cyrene ™< (10 g, 78 mmol, 1 eq.) and CpOMe (150 ml). (E)-But-2-en-2-ylmagnesium bromide 0.5 M in THF (312 ml, 156 mmol, 2 eq.) is added dropwise so that the temperature remained below 15 °C. The mixture is stirred overnight at room temperature. The mixture is then poured into a solution of ice (50 g), water (50 mL) and sat. NH 4 Cl aq . (50 mL). The aqueous phase is extracted with ethyl acetate (3 x 50 mL). The combined organic phases are gathered and concentrated on rotavapor. The concentrate is distilled under vacuum (70 °C, 0.3 mbar). (1S,5R)-4-((E)-but-2-en-2-yl)-6,8-dioxabicyclo[3.2.1]octan-4-ol (3.7 g, 23%) is recovered as a mixture of isomers (42 / 14 / 20 / 24) in the form of colorless liquid with an overall GC purity of 90%. GC-O analysis of the mixture showed that the isomers have a very weak unpleasant smell of dirty mop.

[0059] MS (EI +< ) Isomer 1 : 138 (15), 123 (19), 110 (12), 98 (27), 83 (100), 79 (14), 77 (14), 55 (75), 54 (10), 53 (14), 43 (29), 41 (26), 39 (29); Isomer 2 : 123 (20), 98 (23), 83 (100), 55 (64), 53 (20), 43 (39), 41 (25), 39 (26); Isomer 3 : 123 (27), 98 (21), 83 (100), 55 (61), 43 (29), 41 (29), 39 (19); Isomer 4 : 123 (15), 98 (21), 83 (100), 79 (16), 67 (11), 55 (50), 53 (14), 51 (10), 44 (11), 43 (31), 41 (25), 39 (24).

[0060] 1< H NMR (300 MHz, CDCl 3 ) : 5.53 (dqq, J = 10.2, 7.3, 1.5 Hz, 1H), 5.41 - 5.25 (m, 1H), 4.60 - 4.46 (m, 1H), 4.09 - 3.76 (m, 2H), 2.47 - 2.21 (m, 2H), 2.27 - 1.39 (m, 9H).

[0061] 13< C NMR (75 MHz, CDCl 3 ) : δ 136.32, 135.56, 135.00, 134.73, 126.97, 126.00, 122.21, 121.05, 104.35, 104.14, 104.05, 101.50, 74.36, 74.05, 73.98, 73.75, 73.37, 73.12, 73.04, 72.97, 72.73, 68.01, 67.98, 67.54, 67.35, 31.19, 31.10, 29.89, 29.48, 27.98, 27.84, 27.25, 26.65, 25.74, 25.69, 23.04, 15.62, 15.35, 13.62, 13.53, 12.22. IR (cm -1< ) : 3478(OH), 1126(C-O).

[0062] Formulation Examples: Comparison of performance of fragrance formulations (Frangipani and Floral Oriental Accords) dosed with ethyl vanillin, vanillin, Compound 3A, or dipropylene glycol (DPG), where the amounts are expressed in parts based on mass. TABLE 1: Formulation Example 1 - Frangipani Accord.Frangipani Accord1A1B1C1DTotal8951000100010001000BENZYL SALICYLATE500500500500500HEDIONE ™< 165165165165165PHENYLETHYL ALCOHOL6666666666BENZYL ACETATE3636363636HABANOLIDE ™< 3030303030ISOAMYL SALICYLATE3030303030GAMMA NONALACTONE1515151515GERANIUM BOURBON EO1010101010BIGARANE ™< 1010101010CINNAMYL ACETATE88888TRIPLAL ™< 77777GINGER PURE JUNGLE ESSENCE ™< 66666AQUAL ™< 1%TEC44444INDOL33333METHYL BENZOATE33333PARACRESYL ACETATE22222DIPROPYLENE GLYCOL - DPG1009595105ETHYL VANILLIN5VANILLIN10Compound 3A10

[0063] In Example 1, the Frangipani accord was dosed with: 0.5% w / w ethyl vanillin and 10% w / w DPG (Accord 1A); 1% vanillin and 9.5% w / w DPG (Accord 1B); 1% w / w Compound 3A and 9.5% w / w DPG (Accord 1C); and 10.5% w / w DPG (Accord 1D).

[0064] These accords (1A-1D) were evaluated at 5% w / w in ethanol as an eau de toilette base. Compound 3A (Accord 1C) is really changing the note, bringing an additional leathery facet, besides having a push on the cresolic note, similar to ethyl vanillin (Accord 1A). Compound 3A also brings a sweet effect.

[0065] These accords (1A-1D) were also evaluated at 0.6% w / w in a shampoo base. Ethyl vanillin (Accord 1A) brings a gourmand effect to the note, whereas vanillin (Accord 1B) or Compound 3A (Accord 1C) pushes the jasmine effect, with the Accord 1C sample being less sweet. The mere dilution with DPG (Accord 1D), the accord is less powerful and less floral. TABLE 2: Formulation Example 2: Floral Oriental Accord.Floral oriental accord2A2B2C2DTotal9001000100010001000HEDIONE ™< 350350350350350BENZYL SALICYLATE100100100100100HABANOLIDE ™< 8585858585FLOROL ™< 6060606060cis-3-HEXENYL SALICYLATE6060606060LINALOOL4040404040ORANGE EO3535353535HELIONAL ™< 3232323232ETHYL MALTOL3030303030NEROLI Specialty1818181818GERANIUM BOURBON EO1313131313trans-2-DODECENAL1010101010BENZYL ACETATE88888BENZALDEHYDE88888CIS JASMONE55555GAMMA DECALACTONE33333METHYL CINNAMATE33333INDOL22222COUMARINE22222PINK PEPPER (SCH.TEREBENTH.) PURE JUNGLE ESSENCE ™< 11111DPG35353535135ETHYL VANILLIN100VANILLIN100Compound 3A100

[0066] In Example 2A, a floral oriental gourmand accord was dosed with: 10% ethyl vanillin and 3.5% DPG (Accord 2A); 10% vanillin and 3.5% DPG (Accord 2B); 10% Compound 3A and 3.5% DPG (Accord 2C); and 13.5% DPG (Accord 2D).

[0067] These accords (2A-2D) were evaluated as an eau de toilette base in ethanol. At 5% of each in ethanol, the accords are significantly different. Accord 2A is very caramel, gourmand, whereas Accord 2B is powdery, more distinctively vanilla. The addition of Compound 3A in Accord 2C is changing the olfactive direction by giving a leathery facet to the accord and pushing the phenolic note. However, while not as sweet-powdery as in Accord 2B with vanillin perfume, Compound 3A in Accord 2C brings a sugary effect to the note.

[0068] Notably, Compound 3A is remarkably stable in various bases and provides a fragrant boost of vanilla without the color stability issues with phenolic compounds. For example, a visual comparison of the alcoholic solutions (aged 4 months standing at RT), it was readily noticeable that the samples with vanillin or ethyl vanillin are yellowish in comparison to samples with Compound 3A.

[0069] While the invention has been illustrated by the description of one or more embodiments thereof, and while the embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative product and / or method and examples shown and described. The various features of exemplary embodiments described herein may be used in any combination. Accordingly, departures may be made from such details without departing from the scope of the general inventive concept.

Claims

1. A fragrance composition comprising: one or more compounds having a general Formula I wherein R is selected from the group consisting of methyl and allyl.

2. The fragrance composition according to claim 1, wherein R is methyl, providing (1S,5R)-4-methyl-6,8-dioxabicyclo[3.2.1]octan-4-ol.

3. The fragrance composition according to claim 1, wherein R is allyl, providing (1S,5R)-4-allyl-6,8-dioxabicyclo[3.2.1]octan-4-ol.

4. The fragrance composition according to any one of claims 1 to 3, wherein the compound of general Formula (I) is present in a concentration of between 0.0001 wt% and 99 wt%, based on the total weight of said composition.

5. The fragrance composition according to any one of claims 1 to 4, wherein the compound of general Formula (I) is present in a concentration of between 0.1 wt% and 30 wt%, based on the total weight of said composition.

6. The fragrance composition according to any one of claims 1 to 5, further comprising at least one fragrance ingredient.

7. The fragrance composition according to claim 6, wherein the at least one fragrance ingredient comprises, consists essentially of, or consists of, at least one auxiliary substance.

8. A pharmaceutical, cosmetic, or cleaning composition comprising: the fragrance composition according to any one of claims 1 to 7; and perfuming ingredient(s), flavoring ingredient(s), solvent(s), additive(s), and / or fixative(s).

9. The pharmaceutical, cosmetic, or cleaning composition according to claim 8, wherein R is methyl, providing (1S,5R)-4-methyl-6,8-dioxabicyclo[3.2.1]octan-4-ol.

10. Use of the one or more compounds having a general Formula I wherein R is selected from the group consisting of methyl and allyl: i) as fragrant agent(s); ii) for preparing a fragrance composition such as a perfume composition, a pharmaceutical composition, a cosmetic composition, or a cleaning composition; or iii) for conferring, modifying, improving or enhancing fragrant properties to a fragrance composition such as a perfume composition, a pharmaceutical composition, a cosmetic composition, or a cleaning composition.

11. Use according to claim 10, wherein the one or more compounds having a general Formula I is / are used as fragrant agent(s) in combination with at least one fragrance ingredient.

12. Use according to claim 11, wherein the at least one fragrance ingredient comprises, consists essentially of, or consists of, at least one auxiliary substance.

13. Process for modifying the olfactive properties of a substance, a composition, or an article, said process comprising: a) providing the substance, the composition, or the article; and b) adding one or more compounds having a general Formula I wherein R is selected from the group consisting of methyl and allyl, to said substance, composition, or article; or applying the one or more compounds having a general Formula I to a surface of said article.

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