CA1050043A - Cycloaliphatic unsaturated esters as flavour and odour agents - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

The present invention relates to safranic acid esters having the general formula IV

Description

This invention relates to novel chemical compounds and their use as flavour and odour agents. More specifically this invention relates to cycloaliphatic unsaturated esters which are valuable food and tobacco flavour agents and perfume odour agents.
Increasing attention is being devoted to the prepar-ation and utilization of artificial perfuming and odour-modifying agents in perfumes and perfumed products, and of artificial flavouring and taste modifying agents in foodstuffs, beverages, pharmaceuticals, and to~acco. This attention has been stimulated not only because of the inadequate quantity of natural perfume and flavouring materials available, but, perhaps even more import-antly, because of the need for materials which can combine several natural nuances, will blend better with other perfuming or flavouring compositions, and will give perfumed or flavoured products which can be specifically tailored to a given use and because they can be duplicated at will. This latter factor con-fers a major advantage to artificial perfuming and food flavouring agents, since natural products, such as essential oils, extracts, concentrates, and the like are subject to wide variation because of changes in the quality, type or treatment of the raw material.
This invention provides esters of safranic acid and homologues thereof and with their use as flavour and odour agents.
Safranic acid occurs in three isomeric forms, known as ~ , and y-safranic acid, having the structures I, II, and III
respectively;

~COO~I ~COOH ~COOl:

I ~l II ,~ III ~

"~f,~

For simplicity in referring to the various compounds of this invention, in analogy with the isomers of safranic acid, the following nomenclature is used throughout this specification:

~ COOR ~ = conjugated double bonds in ~ositions 5 ~ ~ / 2 2 (endocyclic) and 4;
4 ~ ~ ~ = conjugated double bonds in positions ~ = conjugated double bonds in positions IV ~ , or -r. 2 (exocyclic) and 3.
~-safranic acid is described in Helv.Chim.Acta 31 (1948) 134 ~-safranic acid in Berichte 74 (1941) 1242 and ~- and y-safranic acids are mentioned in Helv.Chim.Acta 33 (1950) 1746.
Also some methyl-and ethyl esters of safranic acid are described in the literature:
- Ethyl ~-safranate in Helv.Chim.Acta 31 (1948) 134;
- Methyl ~- and y-safranates and ethyl ~- and r-safranates are mentioned in Helv.Chim.Acta 33 (1950) 1746;
- Ethyl ~-safranate is prepared in Helv.Chim.Acta 38 (1955) 1863;
- Methyl ~-safranate is mentioned in Compt.Rend.Ser. C 262 (1966) 1725, in Bull.Soc.Chim.France (1966) 3874, and in Agr.Biol.Chem.
34 (1970) 198;
- Ethyl ~ -, and y-safranates are prepared in Helv.Chim.Acta 54 (1971) 1767;
- Esters of ~ -, and r-safranic acid with saturated alcohols containing 1-4 carbon atoms are also mentioned in Dutch Patent Applications 72.11248 and 73.01451, open to public inspection on August, 17th, 1972, and August, 7th, 1973, respectively.
In these publications the safranates are used as intermediates in syntheses of safranal, damascenones or abscisic acid. However, nowwhere mention is made of the organoleptic properties of these esters.

'~'; ' ' :10~0043 We have now found that the safranic acid esters and some novel homologues thereof possess useful organoleptic pro-perties and can be used for flavouring and perfuming a wide range of products. The compounds of the invention may be used, combined with other flavouring agents, diluents or carriers, for flavouring foodstuffs, beverages or tobacco products; they may be compounded with other odoriferous compounds to make perfumery compositions, in the manner conventional in the perfumery art.
The odoriferous esters of this invention have the general formula IV: 6 5 ~ / COOR2 4 ~ ``~ R
IV
wherein the dotted lines represent two conjugated double bonds in the positions 2 (endocyclic) and ~ (~-isomer), 1 and 3 (~-isomer), or 2 ~exocyclic) and 3 (~-isomer); Rl represents an alkyl group, or, the y-isomers an alkylidene group, with 1-3 carbon atoms; and R2 represents an alkyl- or alkenyl group with 1-4 carbon atoms. The compounds of formula IV wherein Rl is CH3 (~- or ~-isomers) or CH2 (y-isomers) and R2 is CH3 or C2H5 are known compounds, as these esters are the methyl- and ethyl safranates, described in the literature cited above. The other compounds of formula IV are new.
The compounds of this invention may be prepared by methods described in the cited literature or for the homologues of the safranic acid esters in an analogous way. The methods described in the examples are modifications of the method given in Dutch Patent Application 73.01451, pp 11-13, where the ~-, ~-, and ~-safranic acid ethyl esters are prepared from mesityl oxide and ethyl acetoacetate according to reaction scheme A, as intermediates in a synthesis of damascenone analogues.

.. .. ...

COOR2 ~'; +H2 2 ;~J/ 2 _~ IV

//\ R Rl H

REACTION SCHEME A
We have found that the ratio of ~:~:y isomers in the last step of this reaction sequence can be altered by varying the reaction time. In general starting from alkyl or alkenyl aceto-acetates a mixture of compounds IV (with Rl=CH3 or CH2) is obtainedpredominantly consisting of ~-isomer (ca 60 %), and about 20 ~
each of the ~- and ~-isomers. In the syntheses of the compounds with general formula IV withRl containing two or three carbon atoms, extension of the reaction time in the dehydration step leads to the formation of a reaction mixture for over 90 %
consisting of the y-isomer. A shorter dehydration time gives a higher content of the ~- and ~-isomers, although even then the y-isomer will be the major component in the mixture obtained. The three isomers of the compounds with the general formula IV can be separated by preparative gas liquid chromatography. The prepar-ation of the compounds of this invention is illustrated in Example 1 with the synthesis of a mixture of the ~ -, and y-isomers of the compounds with formula IV, wherein R1 = C2H5 (a- or ~-isomers) or C2H4 (~-isomer), and R2=C2H5.
By varying Rl an~ R2 in the condensation reaction bet-ween mesityl oxide and an acylacetic acid ester (see reaction scheme A) other compounds of general formula IV are obtainable.
It will be clear to those skilled in the art that other ways of reducing the cyclohexenone (e.g. Meerwein-Ponndorf reduction) can be used. Examples can be found in the cited journal references.
Analogous to the method described in Example 1 the following compounds of the general formula IV were prepared:

~050~43 _ _ Bo1ling 20 1 2 pointC n D
_ _ _. ._ CH3 or CH2 CH3 37-40/3 mm Hg 1.4820 id C2H5 70-76/5 mm Hg 1.4790 id CH2CH=CH2 78-79/2 mm Hg 1.4884 id CH2CH(CH3)2 68-73/2 mm Hg 1.4747 C3H7 or C3H5 C2H578-82/3 ~n Hg 1.4832 As already mentioned all reaction products obtained contain ~ -, and y-isomers. The y-isomers of formula IV with Rl containing two or three carbon atoms exist in two geometrical isomers, cis and trans, as shown in the following two formulae (IV, with Rl = C2H~).

~OR2 ~COOR2 IV cis-y IV-trans-y The amounts of the two y-isomers, formed by the reaction-sequence described, are broadly equal.
The compounds of the invention have been found to possess very useful organoleptic properties. Although there are minor differences in their flavour and fragrance character, it is not always necessary to separate the isomers because the mixture of isomers can be used as such for the purposes of this invention.
The isomers show closely related smells, as can be seen from the following odour descriptions, drafted by skilled perfumers and flavourists.
- Ethyl safranate (Mixture, ~ y = 20:60:20) (Formula IV, 1 CH3 or CH2~ R2= C2H5) The main impression of this mixture can be described as herbal, ;~ - 5 -spicy (rosemary, spike, laurel) and ruity (apple, prune) with a distinct undertone of roses and wood.
- Ethyl ~-safranate (Formula I~-~, Rl=C~3, R2=C2H5):
The woody, ionone-like undertone is somewhat stronger than in the mixture of the three isomers.
- Ethyl ~-safranate (Formula IV-~, Rl=CH3, R2=C2H5):
The herbal, spicy character is more pronounced, although a great similarity with the mixture does exist.
- Ethyl ~-safranate (Fo~mula IV-y, Rl=CH2, R2= C2H5):
A more fruity character (apple, prune~ can be observed, but the difference with the mixture of the three isomers is small.
- Methyl safranate (Mixture) (Formula 1~, Rl=C~13 or CH2, R2=CH3):
has a ~ess fruity character than ethyl safranate. The herbal, spicy aspects are stronger. In aftersmell there are some sweet hints of tonka.
-Allyl safranate (~ixture) (Formula IV, Rl-CH3 or CH2, R2=C3H5):
The odour character is nearly identical with ethyl safranate, but less intense.
- Isobutyl safranate (Mixture) (Formula IV, Rl=CH3 or CEI2, R2=
i~C4Hg):
The main aspects are herbal~ spicy with a striking pearlike character. Especially suitable for flavouring purposes.
- Ethyl 6,6-dimethyl-2-ethylidene-3-cyclohexenecarboxylate Formula IV, Rl = C2H4, R2 2 5 This ester shows a great odour similarity with ethyl safrana-te, but its odour intensity is probably somewhat greater.
- Ethyl 6,6-dimethyl-2-propylidene-3-cyclohexenecarboxylate Formula IV, Rl = C3H6 R2 2 5 In comparison with ethylsafranate the odour intensity is much smaller. The fruity notes of ethyl safranate have almost complete-ly disappeared, but the herbal, spicy notes are much stronger.
This ester also exhibits an earthy-woody note.

. ~ ~

~lLO~)043 The odour characteristi~s may give some general hints on the usefulness of the compo~lnds of this invention. ilowever, the compounds will nearly always be used in combination with other flavour and fra~rance materials. One can by no means predict whether a compound with a well-defined odour will behave satis-factorily in perfume or flavour compositions. Furthermore, the mere possession of an odour is not sufficient for a compound to be useful as a perfume- or flavour-ingredient. Some of the other requirements are:
- compatability with other perfume and flavour materials and with the substrate to be perfumed or flavoured;
- favourable toxicological and dermatological properties;
- the power to give complicated perfume or flavour compositions a general character or a specific note as conceived by a skilled perfumer or flavourist.
The compounds of this invention fulfil these requirements.
When compounds are tested for possible use in perfume or flavour compositions, threshold values are often determined.
As the compounds of this invention were found to blend very well with the known damascones and damascenones, descrihed in e.g.
British Patent Specificiation 1~240.309 and Dutch Patent Applica-tion 72.11248, and with the homologues of the damascones and damascenones, described in our co-pending Canadian Application Number 220,558 filed Fehruary 21, 1975, the odour threshold value of all these compounds and of some mixtures thereof were deter-mined. The three compounds which are the subject of British Patent Specification 1.240.309, in flavour compositions develop fruity, herblike, winy, woody, floral or waxy flavour notes.
They can be used in e.g. berry flavour compositions, wines, beverages and tobacco products. According to this Patent Specifi-cation they also can be used in perfume compositions of the floral type. The identification of these compounds, "damascones" and "damascenones" (formulae 4,5 and 5) _ q_ lOS,0043 o o o ~ -damascone ~-damascone ~-damascenone (after "Rosa damascena", the essential oil of which contains ~-damascenone) is described in Helv.Chim.Acta 53 (1970) 541, id 54 (1971) 681, id 54 (1971) 1891, Id 55 (1972) 1866, and id 56 (1973) 1503.
~-Damascone was found in tea.
~-Damascone is a constituent of Burley tobacco and of tea.
~-Damascenone is a component of Bulgarian rose oil, Burley tobacco, Greek tobacco, deer tongue, coffee, tea,'apple and raspberry.
In Dutch Patent Application 72.11248 some other analogues are described which have the general formula X~
~"

wherein on two of the places indicated by dotted lines a double bond is present, i.e. in the positions 1 and 4, the positions 1 and 3, the position 2 (exocyclic) and 3 or the position 2 (endocyclic) and 4. In this application the inventors state that the organoleptic prope~ties of the new compounds show major differences in comparison with the known ~- and ~-damascones, ~-damascenone. This is rightfully explained by the unpredictability of organoleptic properties in relation to chemical structures.

From the examples in this patent appllcation it becomes clear that the differences in organoleptic properties do not show or give only minor deviations in the use of the compounds in perfume and flavour compositions.
The invention of copending Canadian application No.
220,558 filed February 21, 1975 relates to cycloaliphatic unsatur-~ - 8 -105()043 ated ketones, which may be a) damasc(en)one homologues havin~ the general formula 10 - 8a -~0(143 o ~ ,,,~
'I ~`

wherein R stands for a hydrogen atom or a methyl radical and wherein the dotted lines represent one double bond in th~ positions 1, 2 endocyclic or 2 exocyclic, or two conjugated double bonds in the positions 1 and 3, 2 endocyclic and 4, or 2 exocyclic and 3;
b) dihydrodamasc(en)ones having the general formulae 11 and 12 O O

the dotted lines in the latter formula representing one double bond in the position 1, 2 endocyclic or 2 exocyclic, or two conjugated double bonds in the positions 1 and 3, 2 endocyclic and 4 or 2 exocyclic and 3; and c) dehydrodamascenones having the general formula 13 wherein the dotted lines represent two conjugated double bonds in the positions 1 and 3, 2 endocyclic and 4 or 2 exocyclic and 3.

Specific compounds comprised by formulae are:
. .
l-crotonoyl-2-ethyl-6.6-dimethyl-1-cyclohexene;
l-crotonoyl-2-ethyl-6.6-dimethyl-2-cyclohexeIIe;
1-crotonoyl-2-ethylidene-6.6-dimethylcyclohexane;
l-crotonoyl-2-ethyl-6.6-dimethyl-1.3-cyclohexadiene;
l-crotonoyl-2-ethyl-6.6-dimethyl-2.4-cyclohexadiene;

r~ .

lOC~00~3 l-crotonoyl-2-ethylidene-6.6-dimethyl-3-cyclohexene;
l-crotonoyl-2-propyl-6~6-dimethyl-1-cyclohexene;
l-crotonoyl-2-propyl-6.6-dimethyl-2-cyclohexene;
l-crotonoyl-2-propylidene-6.6-dimethylcyclohexane, l-crotonoyl-2-propyl-6.6-dimethyl-1.3-cyclohexadiene;
l-crotonoyl-2-propyl-6.6-dimethyl-2.4-cyclohexadiene;
l-crotonoyl-2-propylidene-6.6-dimethyl-3-cyclohexene;
l-butanoyl-2-ethyl-6.6-dimethyl-cyclohexane;
l-butanoyl-2-ethyl-6.6-dimethyl-1-cyclohexene;
1-butanoyl-2-ethyl-6.6-dimethyl-2-cyclohexene;
l-butanoyl-2-ethylidine-6.6-dimethylcyclohexane;
l-butanoyl-2-ethyl~6.6-~imethyl-1.3-cyclohexadiene, l-butanoyl-2-ethyl-6.6-dimethyl-2.4-cyclohexadiene;
l-but-2'-ynoyl-2-ethyl-6.6-dimethyl-1.3-cyclohexadiene;
l-but-2'-ynoyl-2-ethyl-6.6-dimethyl-2.4-cyclohexadiene;
l-but-2'-ynoyl-2-ethylidene-6.6-dimethyl-3-cyclohexene;
The procedure used in described in: Manual on Sensory Testing Methods, A.S.T.M. Special Technical Publication No. 434, Phila-delphia, 1968, Page 30, method 3b and on page 61. To show some of the peculiarities of the compounds of this invention, and the interactions of these compounds with other perfume and flavour agents, results of these tests are given in the table:

3~

1~500~
-~ode Compound Odour threshold Odour description value a) b) A Ethyl safranate(Mixture, 6 x 10 6 General fruity, ~ y= 20:60:20) but not apple-like B Ethyl 6,6-dimethyl-2- 10 x 10 6 Apple-like ethylidene-3-cyclo-hexenecarhoxylate C ~-Damascone c) 1 x 10 Apple--like D B-Damascenone d) 6 x 10 6 Apple-like E Damascenone homologue e) 8 x 10 6 Near threshold:
fruity, in higher concentration coffee-like F Damascone homologue f) 0a8 x 10 Apple-like G A + E (5 : 2) 0~2 x 10 6 Distinctly apple-like.
H B + E (5 : 2) 2 x 10 Apple-like I A + D (5 : 2) 0,6 x 10 Apple-like Notes:
a) All compounds and mixtures were dissolved in odourless diethyl phthalate.
b) The threshold values were determined using layman-observers.
They were asked to give a general odour description. The descrip-tions in the table are quite different from those given by experts.
c) = trans 2,6,6-trimethyl-1-crotonyl-2-cyclohexene, see e.g.

British Patent Specification 1.240.309.
d) = trans 2,6,6-trimethyl-1-crotonyl-1,3-cyclohexadiene, see e.g. British Patent Specification 1.240.309.
e) = The reaction product of EY~ample 9 of our copending Application Number f) - The reaction product of Example 8 of our copending Application Number One can see from this table that the mixtures G, H, and I all ~" ~, , ~ 4 ~

00~3 have considerably lower threshold values than the individual components, this lowering being probably the ~irst occasion in which synergism in the field of olfaction could be substantiated by quantitative data. Equally striking is the fact that a com-bination o~ the compounds with codes A and E has a distinct apple-like odour, whereas the individual components have a general fruity odour, with no reminiscence of the odour of apples.
It turns out therefore that the esters of this inven-tion when used in combination with cycloaliphatic unsaturated ketones such as ~-damascone, ~-damascenone, or one or more of the homologues thereof, which are describea in our copending Canadian Application Number 220,558 specifically enhance the perfuming and flavouring properties of these ketones, making optimal flavour and odour effects attainable. The esters as well as the ketones may be present as isomeric mixtures. To obtain these remarkable effects the relative amounts of the esters of this invention and of the unsaturated ketones can vary from about 1:20 to about 2D:l~
As will be understood by those skilled in the use of flavouring materiàls and perfume agents, it is not possible nor feasible to give specific instructions for the use of the esters of this invention either alone or in combination with said ketones in such arts, as there are too many factors which govern the absol-ute amounts of materials to be used.
Among such factors are the personal preference of the flavour expert or perfumer, the cost of materials, the nature of the particular composition, the flavour or odour effect to be achieved, etc. Nonetheless, it will be readily apparent to experts how to employ the esters of this invention in particular situations.
Perfumery compositions containing the esters of this invention may find use in a wide variety of perfumed materials.
For example such compositions may be used in soap, detergent, or deodorant compositions, in cosmetic preparations such as cologne ~OS1~0~3 waters, toilet waters, face creams, body lotions, talcum powders, sun cream preparations and shave lotions. Flavour compositions containing esters of this invention may find use in the flavouring of foodstuffs, beverages, pharmaceuticals or tobacco. The esters may be used to improve the flavour of beverages such as fruit juices.
In the following Examples, the invention is illustrated in a more detailed manner. All quantities in the Examples 2-11 are expressed on a weight basis. The Examples are not to be considered as necessarily constituting a limitation on the present invention.

-A- Preparation of Ethyl 6,6-dimethyl-2-ethyl-4-oxo-2-cyclohexenecarboxylate.
A mixture of 294 g. of mesityl oxide, 432 g. of ~-propionylacetic acid ethyl ester, 150 g. of cyclohexane and 75 g.
of zinc chloride was stirred at boiling temperature of the mixture during 60 h. The water resulting from the reaction was separated via a Dean-Stark tube.
At room temperature the mixture was stirred during 10 minute with 300 g. of a 10% HCl-solution and 150 g. of cyclohexane.
After washing with water, a NaHCO3-solution and again water, cyclohexane was distilled off from the separated orga~ic layer and the residue fractionated in vacuo which gave 272 g. of a pro-duct, b.p. 126-135 C/2 Torr, n20 1.4788, which had a 90 % content of ethyl 6,6-dimethyl-2-ethyl-4-oxo-2-cyclohexenecarboxylate, as determined by GLC and NM~-analysis.
-B- Preparation of a mixture of Ethyl 6,6-dimethyl-2-ethylidene-3-cyclohexenecarboxylate, Ethyl 6,6-dimethyl-2-ethyl-1,3-cyclohexadienecarboxylate and Ethyl 6,6-dimethyl-2-ethyl-2,4,-cyclohexadienecarboxylate.
A solution of 25 g. of NaBH4 and ~.25 g. of NaO~I in l~)S~V043 100 g. o~ water was added dropwise in 30 minutes into a solution of 270 g. of ethyl 6,6-dimethyl-2-ethyl-4-oxo-2-cyclohexene-carboxylate in 100 g of ethanol. During the addition the re-action vessel was cooled to 35-40 C. The reaction mixture was stirred for an additional 4 hours without cooling, whereby the temperature in the reaction vessel slowly reached room temperature. The reaction mixture was diluted with 200 g. of toluene and washed with 100 ml. of a 10 % acetic acid solution.
After separating and drying 2 g. of p-toluenesulphonic acid was added and the solution was refluxed during 2 hours.
After washing with a 5 % NaHCO3 solution and water, the volatile solvent was removed in vacuo yielding 263 g. of an oily liquid which was subjected to fractional distillation.
The second fraction of the distillate (167 g.) had a boiling point of 74-90 C/ 2 Torr and a nD of 1.4819. It consisted of a mixture of the three title compounds. The ~- and 3-isomers formed 15 and 5 % respectively, the remaining 80 % being the y-isomer.
1) When the reflux time was extended to 7 hours, the only reaction product wa~ the ~-isomer, b.p. 77-80 ~C/ 2 Torr, n20 1.4~35.
EXAMPLE 2.
Perfume compositions of the rose type.
Three rose type compositions were prepared by mixing the following ingredients:
Compound Composition A B C
Cinnamic alcohol 15 20 5 Phenyl ethylalcohol 400 380435 Rhodinol 260 280250 l-Citronellol 160 140150 Phenylacetaldehyde dimethylacetal 40 50 25 Methylionone ~ 15 - 5 Compound Composition ~ B C
Hydroxycitronellal 5 - 10 Gyrane (N) 1) 30 20 15 Phenylethyl propionate 15 30 25 Ger~nyl acetate 10 20 30 Citronellyl ethyl oxalate 20 10 5 Eugenol 10 % sol. 2) 15 5 10 Undecenal 10 % sol. 2) 5 - 5 10 Rose oxide 10 ~ sol. 2) 5 5 5 Methylionone y - 10 Linalool - 10 Lauric aldehyde 10 % sol. 2) - 10 Rosana NB 131 3) - 5 Geranium oil Bourbon - - 10 Rose absolute 10 % sol. 2) - - 5 . _ 1) Fragrance material, available from Naarden International.

2) In diethyl phthalate.

3) Rose base, available from Naarden International.
A. By adding to 99.5 g. of mixture A 0.5 g. of a 1 % solution in diethyl phthalate of ethyl safranate the composition becomes more brillant than the basic composition, with a more pronounced natural character of roses, accentuated by a fruity topnote.
B. By adding to 99.5 g. of mixture B 0.5 g. of a 1 ~ solution in diethylphthalate of ethyl 6,6-dimethyl-2-ethylidene-3-cyclo-hexenecarboxylate, the composition instantly becomes more power-ful and full bodied. The composition obtained has an exceptional brilliancy and a ~lowery, true to nature rose character.
C. By adding to 99 g. of mixture C 1 g. of a 1 % solution of ethyl 6,6-dimethyl-2-propylidene-3-cyclohexenecarboxylate the composition obtained has an improved richness and a more pronounced ~' ~, .

10~043 natural note than the basic composition.
EXAMPLE 3.
Perfume compositions of the Fougère type.
Three fougère type compositions were prepared by mixing the following ingredients:
Compound Composition A B C
Coumarine 30 25 15 Musk ketone 5 5 10 Phenyl ethylalcohol 80 90 100 Oak moss absolute 10 10 5 Amyl salicylate 30 20 40 Rosemary oil 30 35 40 Serpolet oil 10 15 20 Lavender oil French type 260 255 220 Bergamot oil 100 60 120 Lemon oil 40 60 30 Eugenol 10 15 5 Ylang-Ylang oil I 5 10 5 Coriander oil 5 5 Clary sage oil 5 10 10 Geranium oil Bourbon 20 25 20 Musk Rl 1) 10 % sol. 2) 20 30 40 Undecenal 10 % sol. 2~ 10 5 15 Linalool 70 50 75 Methyl nonyl acetaldehyde 10 ~ sol. 2) - 5 Methylionone ~ - 10 5 Tetradecanal 1 % sol. 2) - 5 Thyme oil 10 % sol. 2) - - 10 _ 7~0 745 785 1) Fragrance material, available from Naarden International 2) In diethylphthalate.
A. By adding 1 g. of a 1 ~ solution in diethylphthalate of ethylsafranate to 74 g. of mixture A a considerable increase in brilliancy is noted. The composition becomes richer in character and obtains a striking fruity effect.
B. By adding 0.5 g. of a 1 % solution in diethylphthalate of ethyl 6,6-dimethyl-2-ethylidene-3- cyclohexenecarboxylate to 74.5 g of composition B, the composition gets richer and more full bodied. The composition obtains an enhanced brilliance and the tonality of the perfume is accentuat~d.
C. By adding 1.5 g. of a 1 % solution in diethylphthalate of ethyl 6,6-dimethyl-2-propylidene-3-cyclohexenecarboxylate to 78.5 g. of composition C the odour character of this composition gets a more full and warm body and a remarkable increase in brilliance is noted.
EXAMPLE 4.
Perfume comp itions of the pine-fantasy type.
Three pine-fantasy type compositions were prepared by 20mixing the following ingredients:
Compound Composition A B C
Olibanum resinoid 20 10 10 Elemi oleoresin 20 25 10 Bornyl acetate liquid 550 580 600 Turpentine oil rectified 130 100 110 Orange oil terpenes 150 120 135 Rosemary oil French 5 20 20 Guaiyl acetate 15 10 10 Cistus absolute 10 % sol. 1)10 - 10 Methyl nonyl acetaldehyde 30 40 25 10 ~ sol. 1) .
` f ~05C~3 Compound Composition A B C
Ligustral (~) 2) 10 % sol. 1) 20 15 Juniperberry oil 20 30 20 Oak moss absoluce 10 % sol. 1)20 25 10 Thyme oil 10 % sol. 5 - -Serpolet oil - 20 Origanum oil - - 10 Synthetic Geranium oil - - 5 La~ender oil French - - 5 Laurel leaf oil - - 5 1) In diethyl phthalate 2) Fragrance material, available from Naarden International A. The effect of adding 5 g. of a 1 % solution in diethyl -phthalate of ethylsafranate to composition A (995 g.) is a considerable increase in brilliancy and natural richness of this basic composition.
B. Adding 5 g. of a 1 % solution in diethyl phthalate of ethyl 6,6-dimethyl-2-ethylidene-3-cyclohexenecarboxylate to 995 g of composition B results in a fuller, warmer character of this composition, a greater brilliancy and accentuation of the warm, herbal notes.
C. By adding to 990 g. of mixture B 10 g. of a 1 % solution in diethyl phthalate of ethyl 6,6-dimethyl-2-propylidene-3-cyclo-hexenecarboxylate a composition with an enhanced, full bodied natural character is obtained.
EXAMPLE 5.
Preparation of an imitation apple flavour.
An imitation apple flavour composition was prepared by mixing the following ingredients:

.~ .

10~00~3 Amyl acetate 35 Ethyl butyrate 15 Hexyl acetate 3 Amyl propionate Orange oil Florida o,a Ethyl alcohol 96% 945,6 10~0 An apple beverage was prepared using 0,3 g. of this flavour composition for each litre of finished beverage. Two modifications of the apple flavour composition were made by adding to the composition 25 or 50 ppm of ethyl safranate.
The apple beverages made from these two modifications were compared with the unmodified beverage by a panel of exper-ienced tasters. All members of this panel had a strong preference for the beverages with the addition of ethyl safranate, these beverages being more natural apple-like in odour and taste. No significant preference existed between the beverages containing ethyl safranate, although the difference in concentration was notified.
As can be seen from this example the concentration of ethyl safranate in the finished beverage is far below the odour threshold value of the pure compound. Nonetheless its influence on the odour and taste of the beverage is clearly observable.
(25 ppm in the composition, 0,3 g. of the composition for each litre beverage; so the concentration of ethyl safranate in the beverage is 7.5 x 10 9) EXAMPLE 6.
Preparation of_an_ imitation apple flavour composition.
3~ An imitation apple flavour composition was prepared according to L. Bénézet, La Parfumerie Moderne, 43 (1951), No. 22, P 61 - 78.

~ ' ~`~ ,s 10'~0043 Ethyl acetate 50 Ethyl acetoacetate 200 Ethyl formiate 20 Ethyl butyrate 50 Ethyl hexanoate 20 Ethyl heptanoate 5~
Ethyl octanoate 20 Isoamyl formiate 50 Isoamyl acetate 50 Isoamyl pentanoate 100 Isoamyl hexanoate 50 Isoamyl octanoate 100 Acetaldehyde 50 Geraniol 10 Geranyl formiate 10 Geranyl acetate 10 Phenylethyl pentanoate 20 Benzaldehyde 5 Cinnamyl propionate 50 Diethyl malonate 64 Orange oil Florida 20 Rose oil From this composition a 1 ~ solution in ethanol was prepared.
Part of this solution was used to prepare an apple beverage, using 0.3 g of the ethanolic solution perlitre of finished beverage.
To another part of the ethanolic solution 100 ppm ethyl safranate were added. Using 0.3 ~. of this solution per litre finished beverage another apple flavoured beverage was prepared.
Comparison of the two beverages by a panel of trained flavourist resulted in an unanimous preference for the beverage with the addition of ethyl safranate.

~S00~3 EXAMPLE 7.
. _ Preparation of a raspberry flavour composition.
. _ _ An imitation raspberry flavour composition was pre-pared by mixing the following ingredients:
Geraniol 20 Vanilline 20 Maltol 20 Phenyl ethylalcohol50 p-Hydroxybenzyl acetone 50 Methylionone ~ 100 Ionone ~ 100 Benzyl acetate 100 Isobutyl acetate 100 Ethyl acetate 100 Amyl acetate 100 Ethanol 240 A 1 % solution in ethanol of this composition was used as flavour in a raspberry beverage. Adding 100 ppm of ethyl safranate to the ethanolic solution resulted in an improved beverage, the taste and odour being more natural raspberry~like.
EXAMPLE 8.
Preparation of an imitation raspberry flavour composition.
An imitation raspberry flavour composition was prepared as a modification of the recipe of L. Bénézet, La Parfumerie Moderne, 43 (1951) No. 22, p 61-78.
Acetyl methyl carbinol 3 Diacetyl 2 Ethyl acetate 10 Isobutyl acetate 40 Ethyl hexanoate 10 , - 21 -lOSOQ43 Isoamyl hexanoate 10 Hexyl acetate 10 Hexenyl acetate 10 Benzyl acetate 50 Isoamyl alcohol 10 Hexanol 5 Hexenol 5 Ionone ~ 25 Methylionone ~ 25 Orris (Concrète) oil 15 Anis aldehyde 5 Benzaldehyde 5 Phenyl ethylalcohol 50 Methyl salicylate 10 Bornyl salicylate 10 Clove bud oil 10 Orange oil sweet 50 Geranium oil 10 Coumarine 20 Vanilline 30 Aldehyde C-16 ("so-called") 400 Benzylidene mesityl oxide 100 Ethyl benzoate 10 0.3 g. of a 1 % solution in ethanol was used for each litre of finished beverage. Addition of 100 ppm of ethyl safranate to the alcoholic solution of the flavour composition resulted in a bever-age with a better raspberry flavour.

Perfume compositions of the rose type.
-Three rose type compositions were prepared by mixing 10'0043 the following ingredients:
ound Com~osition A B C
Cinnami.c alcohol 1510 20 Trichloromethylphenylcarbinyl acetate 5 5 Phenyl ethylalcohol 355 3~0 365 Rhodinol 180 160 170 Citronellol 170 140 12 Nerol 20 4~ 70 Phenyl acetaldehyde dimethylacetal 30 40 30 Methylionone a 10 10 10 Guaiyl acetate 10 5 10 Hydroxy citronellal 10 15 17 Gyrane (N) 1) 30 25 20 Phenylethyl propionate 20 25 15 Geranyl acetate 10 10 5 Citronellyl ethyl oxalate 20 25 35 Geranium oil Bourbon 20 20 15 Rose oxide 10 ~ sol. 2) 15 10 5 Rosana NB 131 3) 60 70 80 Rose absolute 5 5 5 lS Fragrance material, available from Naarden International 2) In diethyl phthalate.
3) Rose base, available from Naarden International.
Three modifications of composition A were made:
a) Addition of 1 g. of a 10 % solution in diethyl phthalate of the damascone homologue from Example 8 of our copending Canadian Patent Application Number 220,558, to 98.5 g. of the basic compo-sition. ~ -b) Addition of 0.5 g. of a 1 % solution in diethyl phthalate of l~C~043 ethyl safranate to 98.5 g. of the hasic com~osition.
c) Addition of both 1 g. of the solution mentioned under a) and 0.5 g. of the solution mentioned under b) to 98.5 g. of the basic composition.
Three modifications of composition B were made:
a) Addition of 1 g. of a 10 % solution in diethyl phthalate of the damascenone homologue from Example 9 of our copending Canadian Patent Application, Num~er 220,558 to 98.5 g. of basic composition B.
b) Addition of 0.5 g. of a 1 % solution in diethyl phthalate of ethyl safranate to 9~.5 g. of basic composition B.
c) Addition of both 1 g. of the solution mentioned under a) and 0.5 g of the solution mentioned under b) to 98.5 g. of basic composition B.
Finally three modifications of basic com osition C were made:
a) Addition of 0.5 g. of a 1~ % solution in diethyl phthalate of ~-damascenone to 99.2 g. of the basic composition.
b) Addition of Q.3 g. of a 1 % solution in diethyl phthalate of ethyl safranate to 99.2 g. of basic composition C.
c) Addition of both 0.5 g. of the ~-damascenone solution and 0.3 g. of the ethyl safranate solution to 99.2 g. of hasic composition C.
A panel of 10 trained perfumers was asked to compare the modifications with the basic compositions. In each case the basic composition was judged as being im~roved by the addition of the cycloaliphatic unsaturated ~etone (additions a), or by the additions of ethyl safranate (additions b), but the effect of the addition of both types of compounds to the hasic compositions was in all three casQs judged as showing more than the sum of the effects of addition a) and h), resulting in a composition with a very natural rose character, ha~ing a radiant, warm body, and a well balanced topnote.
XAMPLE 10.
Imitati n apple flavour.
Three modifications of the basic composition of example 5 were made:
A. To 100 g. of the basic composition 2.5 g of a 1 % solution in ethanol of ~-damascenone were added.
B. To 100 g. of the basic composition 5 g. of a 1 % solution in ethanol of ethyl safranate were added.
C. To 100 g. of the basic composition 2.5 g. of a 1 96 solution in ethanol of ~-damascenone and 5 g of a 1 % solution in ethanol of ethyl safranate wére added.
These three modifications and the basic composition were compared in finished apple beverages by a panel of trained flavourists. According to this panel compositions A and B were improvements of the basic composition, but a strong preference existed for the beverage containing composition C, this modification giving the beverage a still more natural taste and odour is com-parison with A and B.
The imitation apple flavours of Example 5 containing 25 or 50 ppm ethylsaffranate and modification C of this Example can be used in flavouring tobacco products a~ described in: Merory, Food Flavorings, Composition, Manufacture and Use, Westport 1968.
EXAMPLE 11.
Imitation raspberry flavour.
Three modifications of the basic composition of example 8 were made:
A. 10 g. of the basic composition were dissolved in 1000 g. of ethanol, 0.2 g. of ethyl safranate was added.
B. 10 g. of the basic composition were dissolved in 1000 g. of ethanol. 0.1 g. of a 10 % solution in ethanol of the damascenone C~ N
homologue of example 9 of our copenaing ~}rrtIs~ Patent Application . jf., , Number 220,558 was added.
C. 10 g. of the hasic composition were dissolved in 1~ g.
of ethanol. 0.2 g. of ethyl safranate and 0.1 g of a 10 %
solution in ethanol of -the damascenone homologue of example 9 of our copending Canadian Patent Application Number 220,558 were added.
From these three modifications and from the basic compositions raspberry flavoured beverages were made, using 0.3 g. of the ethanolic solutions for each litre of finished beverage.
The beverages were compared by a panel of trained flavourists.
Although the beverages made from the modifications A and B were judged as improvements over the beverage made from the basic composition, an unanimous preference existed for the beverage made from composition C. In the heverages made from the basic composition or from the mo~ifications A or B the odour and taste of ~-ionone is clearly observable. The beverage made from modification C is far more round in taste and odour and has a rich natural raspberry character.

- 2~ -

Claims (14)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A safranic acid ester having the general formula IV

wherein the dotted lines represent two conjugated double bonds in the positions 2 endocyclic and 4 (.alpha.-isomer), and 1 and 3 (.beta.-isomer) or 2 exocyclic and 3 (.gamma.-isomer), R1 represents an alkyl group or, in the .gamma.-isomers an alkylidene group with 1-3 carbon atoms and R2 represents and alkyl- or alkenyl group with 1-4 carbon atoms, provided that when R1 is CH3 or CH2, R2 is an alkenyl group with 1 to 4 carbon atoms.

2. An ester as claimed in claim 1 selected from an allyl safranate, ethyl-6,6-dimethyl-2 ethylidene-3-cyclohexene carboxylate and ethyl-6,6-dimethyl-2-propylidene-3-cyclohexene carboxylate.

3. A process for the production of a compound as claimed in claim 1 which comprises dehydrating a compound of the formula wherein R1 and R2 are as in claim 1.

4. A process as claimed in claim 3 in which ethyl-6, 6-dimethyl-2-ethyl-4-hydroxy-2-cyclohexene carboxylate is re-fluxed with p-toluenesulphonic acid during a period of between 2 and 7 hours.

5. A perfume or flavouring composition, containing at least one ester having the formula IV

wherein the dotted lines represent two conjugated double bonds in the position 2 endocyclic and 4 (.alpha.-isomer), 1 and 3 (.beta.-isomer) or 2-exocyclic and 3 (.gamma.-isomer) and wherein R1 represents an alkyl group, or, in the .gamma.-isomers an alkylidene group, with 1-3 carbon atoms and R2 represents an alkyl- or alkenyl group with 1-4 carbon atoms provided that the R1 is CH3 or CH2, R2 is an alkenyl group with 1 to 4 carbon atoms.

6. A composition as claimed in claim 5 in which the compound of formula IV is selected from an allyl safranate;
ethyl-6,6-dimethyl-2-ethylidene 3-cyclohexene carboxylate and ethyl-6,6-dimethyl-2-propylidene 3-cyclohexene carboxylate.

7. A composition as claimed in claim 5 or 6 which also contains at least one damascone or damascenone perfume or flavouring agent.

8. A composition as claimed in claim 5 which also contains an effective quantity of at least one compound selected from those of the formula .alpha.-damascone .beta.-damascone .beta.-damascenone

9. A composition as claimed in claim 5 which also contains at least one compound which have the general formula wherein on two of the places indicated by dotted lines a double bond is present, i.e. in the positions 1 and 4, the positions 1 and 3, the position 2 (exocyclic) and 3 or the position 2 (endocyclic) and 4.

10. A composition as claimed in claim 5 which also contains at least one compound selected from a) damasc(en)one homologues having the general formula 10 wherein R stands for a hydrogen atom or a methyl radical and wherein the dotted lines represent one double bond in the pos-itions 1, 2 endocyclic or 2 exocyclic, or two conjugated double bonds in the positions 1 and 3, 2 endocyclic and 4, or 2 exo-cyclic and 3; b) dihydrodamasc(en)ones having the general formulae 11 and 12.

the dotted lines in the latter formula representing one double bond in the positions 1, 2 endocyclic or 3 exocyclic, or two conjugated double bonds in the positions 1 and 3, 2 endocyclic and 4 or 2 exocyclic and 3, and c) dehydrodamascenones having the general formula 13 wherein the dotted lines represent two conjugated double bonds in the positions 1 and 3, 2 endocyclic and 4 or 2 exocyclic and 3.

11. A composition as claimed in claim 8, 9 or 10 in which the weight ratio of compounds of formula IV to the other compounds is from 1:20 to 20:1.

12. A perfumed or flavoured composition containing a compound of formula IV given in claim 5 wherein R1 and R2 are as in claim 5.

13. A composition as claimed in claim 12 which is a perfumed soap, a detergent, a deodorant or a cosmetic preparation.

14. A composition as claimed in claim 12 which is a flavoured foodstuff, beverage, pharmaceutical or tobacco.