MXPA06010193A - Trisubstituted furans suitable for the preparation of fragrance compositions - Google Patents

Abstract

2,2-Disubstituted 5-methyl-2,5-dihydro- and 2,2-disubstituted 5-methyl-tetrahydrofurans of formula (I) wherein R1 and R2 have the same meaning as described in the specification are useful as odorants.

Description

FURANOS TRl SUBSTITUTES ADEQUATE FOR THE PREPARATION OF COMPOSITIONS OF FRAGRANCE FIELD OF THE INVENTION The present invention relates to trisubstituted furans, namely 5-methyl-2, 5-dihydro-2, 2-dis-substituted and 2, 2-disubstituted 5-methyl-tetrahydrofurans and their use as odorants. This invention also relates to a method for their production and fragrance compositions comprising them. A CKUEIXRIES OF THE INVENTION In the fragrance industry there is a constant demand for new compounds that reinforce or improve the odor notes, or impart new odor notes. It has now been found that certain trisubstituted furans constitute the new and powerful black currant odorants devoid of any sulfur note.

With fruity odor, black currant notes were first used in "A azone" (Hermes, 1974), and became more fashionable as the top notes in perfumery as they can impart naturalness and freshness, and thus constitute alternatives attractive to the water lily-citric, lavender or aldehydic notes. Examples of perfume for this recent trend include "The world is beautiful" (Kenzo, 1997) and "Enamorado De Nuevo" (Yves San Laurent, 1998). Since then, black currant notes have become very Ref.:174736 popular and widely used today, not only in fine fragrances, but also in the cosmetic and toilet segments. However, more black currant odorants, such as the Corps Cassis (4-methyl-4-methylsulfanylpentan-2-one) and Oxano (2-methyl-4-propyl [1, 3] oxatiano) are sulfurous and intense compounds, byproducts with sulfur aroma which can lead to an unpleasant note. Thus, there is a specific need for new black currant odorants devoid of sulfur. BRIEF DESCRIPTION OF THE INVENTION According to, the present invention relates in one of its aspects to a compound of formula (1) Where R1 is methyl, ethyl, propyl or iso-propyl; R2 is a C4-C7 alkyl chain, for example tert-butyl, neo-pentyl, or iso-hexyl; C5-C8 cycloalkyl, for example cyclohexane and cycloheptane; or mono- or disubstituted cycloalkyls of C5 or Ce, such as methylcyclohexyl and dimethylcyclohexyl; and the bond between C-3 and C-4 is a single bond, or the dotted line together with the bond between C-3 and C-4 represents a double bond. The compounds according to the present invention contain several chiral centers, and as such can exist as a mixture of stereo isomers, or they can be resolved as isomerically pure forms. Resolving the stereo isomers added to the complexity of the manufacture and purification of these compounds, and so that they prefer to use the compounds simply as the mixtures of their stereo isomers for economic reasons. However, if it is desired to prepare stereo individual isomers, this can be achieved according to the methodology known in the art, for example by preparative HPLC and GC or by selective stereo synthesis. Particularly preferred compounds of formula (1) are 2-tert-butyl-5-methyl-2-propyl-2, 5-dihydrofuran, 2-tert-butyl-5-methyl-2-propyltetrahydrofuran, 2-tert-butyl-2 -isopropyl-5-methyl-2, 5-dihydrofuran, 2-tert-butyl-2-isopropyl-5-methyltetrahydrofuran, 2-tert-butyl-2-ethyl-5-methyl-2, 5-dihydrofuran, 2-ter -butyl-2-ethyl-5-methyltetrahydrofuran, 2-tert-butyl-2,5-dimethyl-2,5-dihydrofuran, 2-tert-butyl-2,5-di ethyltetrahydrofuran, 2- (3 ', 3' -di ethylcyclohexyl) -2,5-dimethyl-2,5-dihydrofuran, and 2- (3 ', 3'-dimethylcyclohexyl) -2,5-di ethyltetrahydrofuran. The compounds according to the present invention can be used exclusively or in combination with a base material. As used herein, the "base material" includes all known odorant molecules selected from the extensive range of natural products and synthetic molecules currently available, such as essential oils, alcohols, aldehydes and ketones., ethers and acetals, esters and lactones, hetero- and macrocycles, as well as nitrogen-containing compounds, and / or in admixture with one or more ingredients or excipients conventionally used in conjunction with odorants in fragrance compositions, eg, carrier materials , and other auxiliary agents normally used in the art. The following list comprises examples of known odoriferous molecules which can be combined with the compounds of the present invention: essential oils and extracts, for example angelica root oil, bergamot oil, absolute black currant, buchu leaf oil, coriander oil , geranium oil, grapefruit oil, absolute jasmine, lavender oil, lime oil, neroli oil, absolute oak moss, orris root oil, patchouli oil, petitgrain oil, rose oil, or oil ylang-ylang alcohols, for example citronellol, dimethylbenzyl carbinol, eugenol, geraniol, (3Z) -hex-3-enol, linalool, phenylethyl alcohol, Super Muguet®, terpineol, or Undecavertol®. aldehydes and ketones, for example Cetone V ™, damascenone, heliotropin, -hexylcinnamaldehyde, Iso E Super®, β-ionone, Isoraldeine®, Silvial®, or vanillin. ethers and acetals, for example Ambrox ™, Oxane ™ or Spirambrene ™. esters and lactones, for example benzylacetate, coumarin, Hedione®, or hexyl salicylate. hetero- and macrocycles, for example ambrettolide, ethylene brassylate, Exaltolide®, maltol, Moxalone ™, or Nirvanolide®. nitrogen-containing compounds, for example methyl anthranilate, Peonile®, or Stemone®. The compounds of the present invention can be used in a wide range of fragrance applications, for example in any field of fine and functional perfumes, such as perfumes, household products, laundry products, body care products and cosmetics. The compounds can be used in widely varying amounts, depending on the specific use and the nature and amount of other odorant ingredients. The proportion is typically 0.001 to 5 weight percent of the application. In one embodiment, the compounds of the present invention can be employed in a fabric softener in an amount of 0.001 to 0.05 weight percent. In another embodiment, the compounds of the present invention can be used in fine perfumery in amounts of 0.1 to 5 percent by weight, more preferably between 0.1 and 2 percent by weight. However, these values are given only by way of example, since the experienced perfumer can also achieve effects or can create new agreements with lower or higher concentrations. The compounds of the present invention can be employed in the application of fragrances simply by directly mixing the fragrance composition with the application of fragrance, or they can, at an earlier stage, be entrapped with an entrapment material, examples of which include polymers , capsules, microcapsules and nanocapsules, liposomes, film formers, absorbers such as carbon or zeolites, cyclic oligosaccharides and mixtures thereof, or can be chemically bound to substrates, which are adapted to release the fragrance molecule upon application of a stimulus external as light, enzyme, or similar, and then mixed with the application. Thus, the invention further provides a method of manufacturing a fragrance application, comprising incorporating a compound of formula (1) as a fragrance ingredient, or directly mixing the compound upon application or mixing a fragrance composition comprising a compound of formula (1), which can then be mixed into a fragrance application, using conventional techniques and methods. As used herein, the "fragrance application" means any products, such as fine fragrances, for example, perfume water and toilet water.; household products, for example, dishwashing detergents, surface cleaners; laundry products, for example softener, bleach, detergent; body care products, for example shampoo, body wash; and cosmetics, for example deodorants, fade creams, including an odorant. This list of products is given by way of illustration and should not be considered in any way as restrictive. The compounds of the formula (1) can be prepared by the reaction of the magnesium Grignard reagent of 3-butyn-2-ol, prepared according to a general procedure well known in the art, with a corresponding ketone (RxR2CO) giving rise to a alkyne diol. The alkyne diol is then hydrogenated in the presence of a Lindlar catalyst. With a subsequent cyclization of cis-alkenediol in the presence of hydrogenated potassium sulfate leading to the formation of the corresponding 5-methyl-2, 5-dihydro-fur ano. In addition, the compounds of the formula (1) can be prepared by the hydrogenation of the dihydro furans. DETAILED DESCRIPTION OF THE INVENTION The invention is now further described with reference to the following non-limiting examples.

Example 1; 2-tert-butyl-5-methyl-2-propyl-2,5-dihydro furan A solution of 40.7 g (374 mmol) of ethyl bromide in 100 ml of dry tetrahydrofuran is added dropwise over a period of 30 minutes. a stirring suspension of 9.08 g (374 mmol) of magnesium swarf in 5 ml of dry tetrahydrofuran, with the reaction initiated by occasional heating with a heat gun. The reaction mixture was then stirred for an additional 3 h under reflux. The reaction mixture was allowed to cool to room temperature, and a solution of 12.6 g (180 mmol) of but-3-in-2-ol in 80 ml of dry tetrahydrofuran was added dropwise and with stirring. The reaction mixture was then again heated to reflux for 4 h, before removing it from the heating bath. A solution of 25.0 g (195 mmol) of 2,2-dimethyl hexan-3-one in 90 ml of dry tetrahydrofuran was added with stirring for 35 minutes, and the reaction mixture was refluxed with stirring for 2 d more. The reaction mixture was then placed to cool to room temperature, and terminated with 500 ml of a saturated aqueous solution of NH4C1. The aqueous phase is extracted three times with 500 ml of ether each time, the combined organic extracts are dried with sodium sulfate and the solvent is evaporated on a rotary evaporator to provide 32.3 g. of crude 5-tert-butyloct-3-yne-2, 5-diol (90%) as a slightly yellowish oil which was used without further purification. A solution of 20.8 g (105 mmol) of this product in 300 ml of ethanol was hydrogenated by stirring at room temperature and pressure under a hydrogen atmosphere in the presence of 3.11 g (2.92 mmol) of 10% palladium on barium sulfate and 300 mg (2.32 mmol) of quinoline. After 10 h of stirring, the catalyst was filtered on a pad of Celite, and the solvent was stirred on a rotary evaporator to provide 20.7 g of (3Z) -5-tert-butyloct-3-ene-2, 5-diol , crude (99%), of which 19.6 g (98 mmol) were heated for 45 minutes in a Kugelrohr apparatus at 155 ° C / 1280 mbar in the presence of 2.00 g (14.7 mmol) of KHS04. The evaporation product of the reaction was trapped in a bulb at -80 ° C, and further purified by flash chromatography (400 g of silica gel, pentane / ether, 98: 2) to obtain 7.26 g of product. This was then distilled in a Kugelrohr apparatus to provide at 70-80 ° C / 120 mbar, 6.24 g (34%) of the title compound as a colorless odoriferous liquid. IR (film): v = 1110/1047 (v COC), 1365/1353 (ds CH3), 977 (d C = CH), 1466/1480 (das CH3), 1715 (v C = C, ring), 3074 (v C = CH) cm "1. -XH NMR (CDC13): d = 0.88 / 0.91 (t, J = 7.0 Hz, 3H, 3" -H3), 0.90 (s, 9H, l'-Me3), 1.23 / 1.25 (2d, J = 6.5 Hz, 3H, 5-Me), 1.42-1.50 (m, 2H, 2"-H2), 1.68- 1.74 (, 2H, 1" -H2), 4.87-4.88 (m, ÍH, 5-H), 5.55 / 5.57 (2dd, J = 6.0, 2.5 Hz, ÍH, 4-H), 5.70 / 5.72 (2d, J = 6.0 Hz, 1H, 3H). -13C? MR (CDC13): d = 14.9 / 15.0 (2q, C-3"), 17.2 / 17.4 (2t, C-2"), 18.4 / 18.7 (2q, 5-Me), 21.4 / 21.8 (2t , C-1"), 26.1 / 26.7 (2q, l'-Me3), 35.5 / 37.2 (2s, C-1 '), 82.8 / 82.9 (2d, C-5), 98.4 / 98.6 (2s, C- 2), 130.2 / 130.5 / 131.2 / 131.7 (4d, C-3, -4). -MS (El): m / e (%) = 57 (17) [C4H9 +], 83 (9) [C5H70 + J , 125 (100) [M * - C4H9], 139 (8) [M + - C3H7], 167 (5) [M + -CH3].

Description of the smell: Black currant, natural, rich, eucalyptus buds, anise, buchu leaves, slightly green.

Example 2: 2-tert-Butyl-5-methyl-2-propyl tetrahydrofuran A suspension of 2.91 g (10.4 mmol) of 2-tert-butyl-5-methyl-2-propyl-2,5-dihydrofuran and 1.06 g (1.00 mmol) ) of 10% palladium on activated carbon in 60 ml of dry ether is hydrogenated at room temperature for 4 h in a Parr apparatus at 2.5 bar hydrogen pressure. The catalyst was filtered and separated on a pad of Celite, and the solvent was evaporated. The resulting residue was distilled in a Kugelrohr apparatus to provide 75-85 ° C / 20 mbar 2.43 g (80%) of the title compound as a colorless odoriferous liquid. IR (film): v = 1110/1088 (v C-O-C), 1379/1365 (d CH3). 1466/1480 (das CH3), 985 (vr CH2) cm "1. Y = NMR (CDC13): d = 0.88 / 0.91 (t, J = 7.0 Hz, 3H, 3" -H3). 0.90 (s, 9H, l'-Me3), 1.19 / 1.21 (2d, J = 6.0 Hz, 3H, 5-Me), 1.33-1.40 (m, 2H, 2"-H2), 1.41-1.45 (m, 2H, 1"-H2), 1.69-1.76 (, 2H, 3-H2), 1.79-1.88 (m, 2H, 4-H2), 4.05 (br.quint., J = 6.0 Hz, ÍH, 5-H ). - 13C NMR (CDCI3): d = 15.2 / 15.3 (2q, C-3"), 18.0 / 18.2 (2t, C-2"), 21.2 / 21.3 (2q, 5-Me), 26.3 / 26.3 (2q, l'-Me3), 31.2 / 31.5 (2t, C-4), 35.7 / 36.0 (2t, C-3), 38.2 / 38.7 (2t, C-1"), 39.5 / 39.6 (2s, C-1 ' ), 76.6 / 77.0 (2d, C-5), 89.0 / 90.2 (2s, C-2). -MS (El): m / e (%) = 57 (30) [C4H9 +], 71 (100) [ M + - C8H17], 85 (6) [C4H90 +], 127 (76) [M + - C4H9], 141 (5) [M + - C3H7], 169 (5) [M + - CH3].

Description of the smell: Black currant, damask, sweet, natural, rich, somewhat green, full of pine, eucalyptus and facets like a mint.

Example 3: 2-tert-Butyl-2-isopropyl-5-methyl-2, 5-dihydrofuran Following the general procedure of Example 1, 5-isopropyl-6,6-dimethylhept-3-ino-2, 5- was prepared. diol with a yield of 78% by reaction of 2,2,4-trimethylpentan-3-one with the Grignard reagent previously prepared from but-3-in-2-ol. Lindlar hydrogenation of a solution of 18.1 g (90.0 mol) of this material in 300 ml of dry ethanol in the presence of 2.20 g (2.07 mmol) of 10% palladium in barium sulfate and 320 mg (2.48 mmol) of uinoline according to Example 1, after analogous procedure, 17.9 g of (3Z) -5-isopropyl-6,6-dimethylhept-3-ene-2, 5-diol (99%) were obtained, of which 17.2 g (85%) mmol) were heated in a Kugelrohr apparatus at 1552C / 1280 mbar in the presence of 1.71 g (12.5 mmol) of HS0 to provide 8.32 g of a colorless oil after trapping the evaporation of the product at -80 aC and rapid chromatography (400 g). of silica gel, pentane / ether, 98: 2). This product was further purified by the distillation of ugelrohr at 80-902C / 20 mbar to provide 7.52 g (48%) of the title compound as a colorless odoriferous liquid. IR (film): v = 1111/1079 (v COC), 1366/1353 (ds CH3), 983 (d C = CH), 1468/1481 (das CH3), 1712 (v C = C, ring), 3071 (v C = CH) cm "1. AH NMR (CDCl3): d 0.88 / 0.89 / 0.91 / 0.92 (4d, J = 6.0 Hz, 6H, 1" -Me2, 0.95 (s, 9H, l'-Me3) , 1.23 / 1.26 (2d, J = 6.5 Hz, 3H, 5-Me), 2.12 / 2.26 (m, ÍH, 1"-H), 4.80-4.86 (m, ÍH, 5-H), 5.67 / 5.68 ( 2dd, J = 6.0, 2.5 Hz, ÍH, 4-H), 5.73 / 5.75 (2d, J = 6.0 Hz, ÍH, 3-H).

NMR (CDC13): d = 19.6 / 19.7 (2q, 5-Me), 20.6 / 20.8 / 21.3 / 21.7 (4q 1"-Me2), 26.5 / 27.2 (2q, -1 '-Me3), 31.4 / 34.1 (2d, C-1"), 37. 6 / 40.6 (2s, C-1 '), 82.1 / 82.2 (2d, C-5), 99.6 / 99.7 (2s, C-2), 128.5 / 128.6 / 130.4 / 131.1 (4d, C-3, -4 ). -MS (El): m / e (%) = 57 (100) [C4H9 +], 83 (45) [C5H70 +], 125 (67) [M + -C4H9], 139 (56) [M + -C3H7], 167 (5) [M + -CH3].

Odor description: Black currant, fruit, grapes, fresh with slightly metallic green nuances.

Example 4: 2-tert-Butyl-2-isopropyl-5-methyl tetrahydrofuran Following the general procedure of Example 2, 2-tert-butyl-2-isopropyl-5-methyltetrahydrofuran was prepared from 3.61 g (19.8 mmol) of 2-tert-butyl-2-isopropyl-5-methyl-2,5-dihydrofuran by hydrogenation in the presence of 1.21 g (1.14 mmol) of palladium in 10% activated carbon. Purification of the crude product by Kugelrohr distillation at 85-95aC / 20 mbar to obtain 3.42 g (93%) of the title compound as a colorless odoriferous liquid. IR (film): v = 1085 (v COC), 993 (vr CH2), 1382/1366 (ds CH3), 1478 (das CH3) cm "1. -XH NMR (CDC13): d = 0.89 / 0.92 (2d) , J = 6.5 Hz, 6H, 1"-Me2), 0.94 (s, 9H, l'-Me3), 1.19 / 1.23 (2d, J = 6.0 Hz, 3H, 5-Me), 1.75-1.79 (, 2H , 4-H2), 1.80-1.88 (m, 2H, 3-H2), 2.06 / 2.25 (2 sept., J = 7.0 Hz, 1H, 1"-H), 3.97-4.05 (m, ÍH, 5-H). -13C NMR (CDC13): d = 19.7 / 20.6 (2q, 5-Me), 20.6 / 20.7 / 20.8 / 20.9 (4q, 1"-Me2), 26.8 / 27.0 (2q, l- Me3), 27.1 / 27.2 (2t, C-4), 29.2 / 33.3 (2d, Cl "), 34.4 / 35.9 (2t, C-3), 39.1 / 40.1 (2s, C-1 '), 75.8 / 76.0 (2d, C-5), 91.8 / 92.4 (2s, C-2). -MS (El): m / e (%) = 57 (95) [C4H9 +], 71 (100) [M + C8H17], 85 (17) [C5H90 +], 127 (61) [M + -C4H9], 141 (77) [M + -C3H7], 169 (5) [M + CH3].

Odor description: Blackcurrant, fruity, green, sweet, similar to coumarin with floral and camphor shades.

Example 5: 2-tert-Butyl-2-ethyl-5-methyl-2, 5-dihydrofuran Following the general procedure of Example 1, 5-ethyl-6,6-dimethylhept-3-ino-2, 5- was prepared. diol with 83% yield by the reaction of 2,2-dimethylpentan-3-one with the Grignard reagent previously prepared from but-3-in-2-ol. Lindlar hydrogenation of a solution of 32.1 g (161 mmol) of this material in 400 ml of dry ethanol in the presence of 2.81 g (2.64 mmol) of 10% palladium in barium sulfate and 1.05 g (8.12 mmol) of quinoline provided after the standard procedure 31.4 g of (3Z) -5-ethyl-6,6-dimethylhept-3-ene-2, 5-diol at (97%), of which 21.2 g (112 mmol) are cyclized at 155 ° C / 280 mbar in the presence of 2. 55 g (18.7 mmol) of KHS04 to provide after purification by flash chromatography (600 g of silica gel, pentane / ether, 98: 2) 10.1 g of the corresponding dihydrofuran. Distillation at 70-80 ° C / 20 mbar gives 6.62 g (36%) of the title compound as a colorless odoriferous liquid. IR (film): v = 1102/1084 (v COC), 967 (d C = CH), 1365/1352 (ds CH3), 1465/1479 (das CH3), 1705 (v C = C, ring), 3073 (v C = CH) cm "1. XE NMR (CDC13): d = 0.77 / 0.81 (2t, J = 7.5 Hz, 3H, 2" -H3), 0.91 / 0.93 (2s, 9H, l'-Me3) , 1.24 / 1.26 (2d, J = 6.5 Hz, 3H, 5-Me), 1.53-1.65 (m, 2H, 1"-H2), 4.82-4.93 (m, 1H, 5-H), 5.54 / 5.56 ( 2dd, J = 6.0, 2.5 Hz, ÍH, 4.H), 5.74 / 5.76 (2d, J = 6.0 Hz, 1H, 3-H). -13C NMR (CDC13): d = 8.1 / 9.3 (2q, C -2"), 21.1 / 21.4 (2q, 5-Me), 24.9 / 26.8 (2t, C-1"), 25.8 / 27.4 (2q, l'-Me3), 36.6 / 39.4 (2s, C.l '), 82.5 / 82.8 (2d, C-5), 98. 4 / 98.7 (2s, C-2), 129.3 / 129.8 / 131.2 / 131.8 (4d, C-3, -4). - MS (El): m / e (%) = 57 (26) [C4H9 +], 83 (6) [C5H70 +], 111 (100) [M + -C4H9], 139 (9) [M + -C2H5], 153 (3) [M + CH3].

Odor description: Alcanforado, frutal, blackcurrant, fresh, with green metallic and animalic nuances.

Example 6: 2-tert-butyl-2-ethyl-5-methyl tetrahydrofuran Analogous to the procedure of Example 2, by hydrogenation of 3.12 g (18.4 mmol) of 2-tert-butyl-2-isopropyl-5-methyl-2, 5-dihydrofuran in the presence of 1.20 g (1.12 mmol) of palladium 10% in activated charcoal. Kugelrohr distillation of the reaction product gave 70-80 ° C / 20 mbar 3.42 g (93%) of the title compound as a colorless odoriferous liquid. IR (film): v = 1106/1083 (v C-O-C), 977 (vr CH2), 1364/1380 (das CH3), 1479 (das CH3) cm-1. 1H NMR (CDC13): d = 0.84-0.95 (m, 3H, 2"-H3), 0.90 / 0.92 (2s, 9H, l'-Me3), 1.20 / 1.22 (2d, J = 8.0 Hz, 3H, 5 -Me), 1.36-1.46 (m, 2H, 3-H2), 1.58-1.76 (m, 2H, 1"-H2), 1.79-1.93 (m, 2H, 4-H2), 3.94-4.11 (m, ÍH, 5-H). -13C? MR (CDC13): d = 8.9 / 9.0 (2q, C-2"), 20.9 / 21.0 (2q, 5-Me), 26.0 / 26.5 (2q, 1 '-Me3), 27.9 / 28.0 (2t , C-1"), 28.7 / 30.2 (2t, C-3), 35.3 / 35.8 (2t, C-4), 38.0 / 39.3 (2s, C-1 '), 76.5 / 76.7 (2d, C-5 ), 89.8 / 90.1 (2s, C-2). -MS (El): m / e (%) = 57 (100) [C4H9 +], 85 (7) [C5H90 +], 113 (59) [M + -C4H9], 141 (21) [M + -C2H5], 153 (5) [M + CH3].

Odor description: Fruity, with mint flavor, camphorate, black currant, with metallic and animal nuances.

Example 7: 2-tert-butyl-2,5-dimethyl-2,5-dihydrofuran Following the general procedure of Example 1, 5,6,6-trimethylhept-3-ino-2,5-diol was prepared with 96 % yield by reaction of 3, 3-dimethylbutan-2-one with the Grignard reagent previously prepared from but-3-in-2-ol. The Lindlar hydrogenation of 10.2 g (60.0 mol) of a solution of this material in 200 ml of dry ethanol in the presence of 960 mg (0.90 mmol) of palladium 10% in barium sulfate and 360 mg (2.78 mmol) of quinoline provides after the usual procedure 10.2 g (100%) (3Z) -5,6,6-trimethylhept-3-ene-2, 5-diol, of which 9.80 g (57.0 mmol) were cyclized in a Kugelrohr apparatus to 155 ° C / 280 mbar in the presence of 1.14 g (8.37 mmol) of KHS04 to provide after rapid gel chromatography (200 g of silica gel, pentane / ether, 98: 2) 2.61 g of the corresponding dihydrofuran. Vacuum distillation at 45-50 ° C / 20 mbar gave 2.35 g (26%) of the title compound as a colorless odoriferous liquid. IR (film): v = 1102/1095 (v C-O-C), 1367/1350 (das CH3). 946 (d C = CH), 1454/1479 (das CH3), 1709 (v C = C, ring), 3075 (v C = CH) cm "1. NMR (CDC13): d = 0.91 / 0.92 (2s, 9H, 1'-Me3), 1.21 / 1.22 (2s, 3H, 2-Me), 1.24 / 1.26 (2d, J = 6.5 Hz, 3H, 5-Me), 4.82-4.92 (, 1H, 5-H) ), 5.56 / 5.62 (2dd, J = 6.0, 1.5 Hz, 1 H, 4-H), 5.76 / 5.79 (2d J = 6.0 Hz, lH, 3-H). -13C NMR (CDC13): d = 20.9 / 21.1 (2q, 5-Me), 23.3 / 24.2 (2q, 2-Me), 25.7 / 26.1 (2q, l'-Me3), 36.2 / 38.3 (2s, C-1 '), 80.1 / 82.4 ( 2d, C-5), 95.0 / 95.2 (2s, C-2), 129.8 / 130.4 / 132.1 / 132.7 (4d, C-3, -4). -MS (El): m / e (%) = 57 (10) [CH 9 +], 83 (5) [C 5 H 70 +], 97 (100) [M + -C 4 H 9], 139 (5) [M + -CH 3].

Odor description: Blackcurrant, citrus, lime, green and slightly fatty.

Example 8: 2-tert-butyl-2, 5-dimethyl tetrahydrofuran According to the procedure of example 2, by hydrogenation of 1.62 g (10.3 mmol) of 2-tert-butyl-2,5-dimethyl-2,5-dihydrofuran in presence of 600 mg (0.56 mmol) of palladium 10% in activated carbon. Kugelrohr distillation at 45-50 ° C / 20 mbar afforded 1.37 g (82%) of the title compound as a colorless odoriferous liquid. IR (film): v = 1102 (v COC), 1368/1380 (ds CH3), 1473/1478 (das CH3), 953 (vr CH2) cm "1. XB NMR (CDC13): d = 0.92 (s, 9H, l'-Me3), 1.13 / 1.15 (2s, 3H, 2-Me), 1.19 / 1.21 (2d, J = 6.0 Hz, 3H, 5-Me), 1.32-1.57 (m, 2H, 3-H2 ), 1.98-2.01 (m, 2H, 4-H2), 3.88-4.12 (m, 1 H, 5-H). -13C NMR (CDC13): d = 20.9 / 22.4 (2q, 5-Me), 22.1 /24.3 (2q, 2-Me), 25.7 (q, l'-Me3), 26.5 / 27.3 (2t, C-3), 33.9 / 34.4 (2t, C-4), 36.8 / 37.8 (2s, C-) 1 '), 73.6 (d, C-5), 87.6 (s, C-2). -MS (El): m / e (%) = 57 (28) [C4H9 +], 85 (5) [C4H90 +] , 99 (100) [M + -C 4 H 9], 141 (8) [M + -CH 3].

Odor description: Green, camphorated, resembling black currant with a slight reminiscence to the orange flowers.

Example 9j 2- (3 ', 3' -Dimethylcyclohexyl-2,5-dimethyl-2,5-dihydrofuran) Following the general procedure of Example 1, 2- (3 ', 3'-dimethylcyclohexyl) hex-3-ino were prepared -2, 5-diol with 62% yield by the reaction of l- (3 ', 3'-dimethylcyclohexyl) ethanone with the Grignard reagent previously prepared from but-3-in-2-ol The hydrogenation of Lindlar of 10.0 g (44.6 mmol) of a solution of this material in 250 ml of dry ethanol in the presence of 740 mg (0.695 mmol) of palladium 10% in barium sulfate and 290 mg (2.24 mmol) of quinoline provided after the usual procedure, 9.82 g of (97%) (3Z) -2- (3 ', 3 • -dimethylcyclohexyl) hex-3-ene-2, 5-diol, which were cyclized in a Kugelrohr apparatus at 180 ° C / 20 mbar in the presence of 430 mg (3.16 mmol) of KHS04. The resulting product was purified by flash chromatography on gel (200 g of silica gel, pentane / ether, 99: 1) and the subsequent Kugelrohr distillation at 55-60 ° C / 0.1 mbar to provide 1.46 g (16%) of the composed of the title as a colorless odoriferous liquid. IR (film): v = 824 (d C = CH), 1085/1105 (v COC), 1366/1350 (dB CH3), 970 (vr CH2), 1453 (das CH3) cm "1. XH NMR (CDC13 ): d = 0.84-1.74 (m, 9H, l'-H, 2 '-, 4' -, 5 '-, 6' - H2), 0.87 / 0.88 / 0.90 / 0.91 (2s, 6H, 3'- Me2), 1.20 / 1.21 (2s, 3H, 2-Me), 1.24 / 1.25 / 1.25 / 1.26 (4d, J = 6.5 Hz, 3H, 5-Me), 4.81-4.92 (m, ÍH, 5-H) , 5.62 / 5.64 / 5.64 / 5.65 (4dd, J = 6.0, 1.5 Hz, 1 H, 4-H), 5.67 / 5.68 / 5.69 / 5.70 (4d, J = 6.0 Hz, 1H, 3-H). NMR (CDCI3): d = 14.0 / 21.5 / 21.6 / 22.3 (4q, 5-Me), 22.3 / 22.4 (2t, C-5 '), 23.2 / 23.9 / 24.6 / 24.7 / 26.6 / 28.2 (6q, 2 - Me, 3 '-Me axial), 27.2 / 27.8 / 27.9 / 28.2 (4t, C-6'), 30.7 / 30.8 (2s, C-3 '), 33.6 / 34.1 (2q, 3' -Me equat.) , 39.1 / 39.2 (2t, C-2 '), 40.7 / 41.4 (2t, C-4'), 42.3 / 42.5 / 43.4 / 43.5 (4d, C-1 '), 79.9 / 80.0 / 81.7 / 81.8 (4d , C-5), 92.3 / 92.4 / 92.5 / 92.6 (4s. C-2), 129.9 / 130.0 / 130.4 / 130.5 / 132.1 / 132.2 / 132.6 / 133.0 (8d, C-3, -4), -MS ( El): m / e (%) = 43 (14) [C3H7 +], 55 (6) [C4H7 +], 69 (6) [C5H /], 79 (4) [M + -C8 H15-H20] .97 ( 100) [M + -C8 H15], 175 (1) [M + -CH3-CH3], 193 (1) [M + -CH3], 208 (1) [M +].

Odor description: Fruity, black currant, grapefruit, tomato wine, natural green with apple and rhubarb aspects.

Example 10 2- (3 ', 3' -Dimethylcyclohexyl) -2,5-dimethyl tetrahydrofuran According to the procedure of Example 2, by hydrogenation of 1.00 g (4.80 mmol) of 2- (3 ', 3'-dimethylcyclohexyl) -2,5-dimethyl -2,5-dihydrofuran in the presence of 100 mg (0.0940 mmol) of palladium 10% in activated carbon. Kugelrohr distillation at 65-70 ° C / 0.1 mbar to provide 690 mg (68%) of the title compound as a colorless odoriferous liquid IR (film): v = 1094 (v COC), 953 (vr CH2), 1455 (das CH3), 1374 (ds CH3) cm "1. XH NMR (CDCl3): d = 0.82-1.82 (m, 11H, l'-H, 3-, 2 '~, 4' -, 5'-, 6'-H2), 0.89 / 0.91 (2s, 6H, 3'-Me2), 1.10 / 1.11 (2s, 3H, 2-Me), 1.20 / 1.23 (2d, J = 6.0 Hz, 3H, 5-Me), 1.93-2.09 ( m, 2H, 4-H2), 3.94-4.09 (m, 1 H, 5-H). -13C NMR (CDC13): d = 21.2 / 21.3 / 21.9 / 22.4 / 23.3 / 24.2 / 24.4 / 24.7 (q, 2-, 5-Me, 3 '-Me axial), 22.5 / 22.6 (2t, C-5 '), 27.6 / 27.7 / 27.8 / 27.8 (4t, C-3), 30.7 / 30.8 (2s, C-3'), 33.7 / 33.8 (2q, 3 '-Me equat.), 33.7 / 34.0 / 34.5 / 35.2 / 35.6 /36.1 (6t, C-4, -6 '), 39.4 / 40.8 / 41.0 / 41.2 (4t, C-2', - '), 43.2 / 43.4 / 43.5 / 43.6 (4d, C-1' ), 73.4 / 73.5 / 75.0 / 75.1 (4d, C-5), 85.0 / 85.1 (2s, C-2). -MS (El): m / e (%) = 43 (38) [C3H7 +], 55 (9) [C4H7 +], 69 (6) [C5H9 +], 81 (3) [M + -C8 H15-H20], 99 (100) [M + -C8 H15], 111 (3) [CHβ-CHis], 138 (1) [CH10-CH? 8+], 177 (1) [M + -CH3-H20], 195 (2) [M + -CH3].

Description of the smell: Sweet, fruity floral, with green facets and similar to black currant.

Example 11: Floral Fruity Agreement for Female Perfumes Ingredient Parts by weight 1. Bencil acetate 40 2. 2-Cyclohexyl-2-phenylacetonitrile 80 3. 1% Damascenone in dipropylene glycol 30. y-Decalactone 4 5. 3,7-Dimethyloct-6-en-l-ol 10 6. 1, 1-Dimethyl-2-phenylethyl acetate 20 7. 1, l-Dimethyl-2-phenylethyl butanoate 20 8. Ethyl butanoate 10 9. Ethyl maltol 10% in dipropylene glycol 4 10. Ethyl 2-methylbutanoate 2 11. Geraniol 240 12. 3,3,4,6,6-Hexamethyl-la, 2,3,4,5,6,7,7a-octahydronapto [2, 3-b] oxirene 50% in triethyl citrate 50 13. (3Z ) -Hex-3-en-l-ol 4 14. (3Z) -Hex-3-en-l-yl acetate 4 . 2-Hexylcyclopent-2-en-l-one 10% in DPG 12 16. 2-Hexyl-3-phenylprop-2-enal 80 17. 3- (4-lsobutylphenyl) -2-methylpropanal 200 18. Methyl dihydrojasmonate 80 19. 8-Methyl--ionone 60 . ? -Undecalactone 10 21. 2-tert-Butyl-5-methyl-2-propyltetrahydrofuran 40 1000 2-tert-Butyl-5-methyl-2-propyltetrahydrofuran is added to these arrangements of floral-fruity raspberry a sophisticated note of blackcurrant which brings diffusivity, freshness and naturalness. In addition, this compound rounds the composition out of and increases the volume, without incorporating the unpleasant connotation of sulfur as is usually the case when using black currant odorants. For that reason, it turns this on the other hand the fruit agreement within a solid foundation for a multifaceted feminine fragrance.

Example 12: Fantasy Fruity Green Fragrance for use in Cosmetics Ingredient Parts by weight 1. l, 3-Benzodioxol-5-carboxaldehyde 16 2. 2-tert-butylcyclohexyl acetate 80 3. Coumarin 24 4. Dihydromyrcenol 80 . Ethyl Acetoacetate 32 6. Ethyl 1,3-dioxolan-2-yl-2-methylacetate 16 7. Ethyl 3-methyl-3-phenylglycidate 4 8. Ethyl oxyhydrate 4 9. (3Z) -Hex-3-en-l-yl acetate at 10% in DPG 8 . Hexil acétate 16 11. 4- (4-Hydroxyphenyl) -2-butanone (N112) at 10% in DPG 8 12. a-Ionona 16 13. Iso-E-Super 32 14. Linalool 160 . Linalil acetate 130 16. Aceil acetate 50 17. 3-Fenilprop-2.enal 4 18. 4-Methoxybenzaldehyde 80 19. 8-Methyl-a. -oneone 160 . 5-Methyl-3-heptanone oxime 16 21. 1,7,7-Trimethyl-2 '- (isopropyl) spiro- (bicyclo [2.2.1] heptane-2,4' - [1,3] dioxan) at 50% in isopropyl myristate 32 22. y-Undecalactone 32 23. 2- (3 ', 3' -Dymethylcyclohexyl) -2,5-dimethyl-2,5-dihydrofuran 10 1010 Although only 1% is used, 2- (3 ', 3'-dimethylcyclohexyl) -2,5-dimethyl-2,5-dihydrofuran harmonizes the composition with a sophisticated, sparkling touch of blackcurrant. It brings naturalness to the composition and concludes with the fruity aspects of this imaginary fragrance for use in cosmetics.

Example 13: Fragrance of Red Berries for Use in Shampoo Ingredient Parts by weight 1. Allil hexanoate 0.40 2. Alil pentyloxyacetate 0.50 3. Benzaldehyde 2.00 4. 1, 3-Benzodioxol-5-carboxaldehyde 6.00 . 2-tert-butylcyclohexyl acetate 70.00 6. 4-tert-Butylcyclohexyl acetate 1.00 7. 2-Cyclohexyl-2-phenylacetonitrile 5.00 8. a-Damascona 1.00 9. Decanal 0.60 10. Dihydromircenol 15.00 11. Dihydro-5-pentyl-2 (3H) -furanone 10.00 12. 2, 4-Dimethylcyclohex-3-encarboxaldehyde 4.00 13. 3, 7-dimethylnone-2,6-dieneitrile 0.20 14. 3, 7-dimethylnone-1, 6-dien-3-ol 60.00 . 1, l-Dimethyl-2-phenylethyl butanoate 3.00 16. Dipropylene Glycol (DPG) 57.91 17. Dodecahydro-3a, 6, 6, 9a-tetramethyl-naphtho- (2, lb) -furan 0.10 18. Ethyl acetate 1.00 19. Ethyl acetoacetate 1.00 . Ethyl butanoate 0.20 21. Ethyl 2-ethyl-6.6.dimethylcyclohex-2-enecarboxylate 5.00 22. Ethyl heptanoate 1.00 23. Ethyl maltol 0.10 24. Ethyl 2-methylbutanoate 2.00 . 6-Ethyl.3-methyloct-6-en-l-ol 5.00 26. Ethyl-3-methyl-3-phenylglycidate 7.00 27. trans-8-Ethyl-l-oxaspiro [4.5] decan-2-one at 1% in triethyl citrate 2.00 28. Ethyl vanillin 0.05 29. 4,6,6,7,8,8-Hexamethyl-1, 3,4,6,7,8-hexahydrocyclopenta [g] benzopyanate at 75% in diethyl phthalate 400.00 30. Hexyl salicylate 140.00 31. l-. { 4-Hydroxyphenyl) butan-3-one 70.00 32. ß-Ionona 28.00 33. Isoamil acetate 5.00 34. Iso-E-Super 50.00 . (-) -? - Mentan-3-ol 0.50 36. 4, 7-Methane-lH-3a, 4, 5.6, 7, 7a-hexahydro-inden-6-yl acetate 5.00 37. 4-Methoxybenzaldehyde 0.50 38. Methoxyphenylbutanone 2.00 39. Methyl anthranilate 0.20 40. 4-Metildec-3-en-5-ol 0.20 41. Methyl dihydrojasmonate 40.00 42. 2-Methyl-3- (4-isopropylphenyl) propanal 1.30 43. (E) -Methyloctane-4,7-dienoate 0.30 44. (10Z) -13-Methyloxacyclopentadec-10-en-2-one 5.00 45. 50% cis-2-Methyl-4-propyl-l, 3-oxathiano in triethyl citrate 0.09 46. Phenoxyethyl isobutanoate 243.00 47. 2-Phenylethanol 30.00 48. 1-Phenylethyl acetate 2.00 49. Prenil acetate 0.30 50. 2, 4, 4, 7-Tetramethylnon-6,8-dien-3-one oxime at 0.50 51. 1- (2,6,6-Trimethyl-2-cyclohexen-1-yl-hepta-1, 6-dien-3-one 0.05 52. ? -Undecalactone 5.00 53. 2- (3 ', 3' -Dimethylcyclohexyl) -2,5-dimethyl-2,5-dihydrofuran 10.00 1300 In a dosage of less than 1%, 2- (3 ', 3'-dimethylcyclohexyl) -2,5-dimethyl-2,5-dihydrofuran adds to the composition a fruity, juicy appearance imparting a sweet, sweetened, however, natural tonality. Dihydrofuran mixed very well with the other compounds of this fruity fragrance, makes it rounder and more complex. Its note of black currant harmonizes very well with the musk and the notes of the floral ionones, without dominating the fragrance.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (7)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property.

1. A compound of formula (1) characterized in that R1 is methyl, ethyl, propyl or iso-propyl; R2 is a branched C4-C7 alkyl, Cs-Cs cycloalkyl, or mono- or disubstituted cycloalkyl of C5 or C6, and the bond between C-3 and C-4 is a single bond, or the dotted line together with link between C-3 and C-4 represents a double bond. With the proviso that the compound of formula (1) is not 2-isopentyl-2,5-dimethyltetrahydrofuran. 2. A compound according to claim 1, characterized in that it is selected from the group consisting of 2-tert-butyl-5-methyl-2-propyl-2, 5-dihydrofuran, 2-tert-butyl-5-methyl-

2. -propytetrahydrofuran, 2-tert-butyl-2-isopropyl-5-methyl-2, 5-dihydrofuran, 2-tert-butyl-2-isopropyl-5-methyltetrahydrofuran, 2-tert-butyl-2-ethyl-5-methyl -2, 5- dihydrofuran, 2-tert-butyl-2-ethyl-5-methyltetrahydrofuran, 2-tert-butyl-2, 5-dimethyl-2, 5-dihydrofuran, 2-tert-butyl-2, 5 - dimethyltetrahydrofuran, 2- (3 ', 3'-dimethylcyclohexyl) -2,5-dimethyl-2,5-dihydrofuran, and 2- (3', 3'-dimethylcyclohexyl) -2,5-dimethyltetrahydrofuran.

3. The use as odorant of a compound of formula (1). wherein R 1 is methyl, ethyl, propyl or iso-propyl; R2 is a branched C-C7 alkyl, Cs-C8 cycloalkyl, or mono- or disubstituted cycloalkyl of C5 or Cß, and the bond between C-3 and C-4 is a single bond, or the dotted line together with link between C-3 and C-4 represents a double bond.

4. A flavor or fragrance composition, characterized in that it comprises a compound of formula (1) as defined according to claim 2 or 3.

5. A method of manufacturing a flavor or fragrance composition, characterized in that it comprises the step of of the incorporation of a compound of formula (1) as defined in accordance with claim 2 or 3, in a base material.

6. A method of manufacturing a fragrance application, characterized in that it comprises the incorporation of a compound of formula (1) as defined according to claim 2 or 3.

7. A method according to claim 6 characterized in that the application of Fragrance is selected group consisting of perfumes, household products, laundry products, body care products and cosmetics.