DE2433199A1 - NEW ALKENALS AND METHODS FOR THEIR PRODUCTION - Google Patents

Description

25 561 n / wa

INTERNATIONAL FLAVORS & FRAGRANCES INC. NEW YORK, NoY./USA

New alkenals and methods of making them

The invention relates to certain new 2-alkylidene-3-alkenals and to methods of making 2-alkylidene-3-alkenals.

By the method according to the invention are direct

509808/1085 -2-

Methods for the preparation of 2-alkylidene-3-alkenals in good yields either in certain ratios of 2-alkylidene-cis-3-alkenal to 2-alkylidene-trans-3-alkenal or as essentially the entire 2-alkylidene-cis-3-alkenal isomer or as essentially all of the 2-alkylidene-trans-3-alkenal isomer created.

In brief, the methods according to the invention comprise the process steps of (1) reaction of an aliphatic OK / -ß-unsaturated aldehyde with a halogen with production of the corresponding <k-halo-aldehyde derivative; (2) either (i) the reaction of the ^ -haloaldehyde derivative with an alkyl magnesium halide Grignard reagent, hydrolysis of the resulting product to form a hydroxyhaloalkene and dehydration of the resulting hydroxyhaloalkene with formation of an alkylidene-trans-alkene halide or (ii) reaction of the C ^ -halogenaldehyde derivative with a trisubstituted alkylidenephosphorane or one Alkylidene phosphoric triamide to produce a mixture of alkylidene-cis-alkene halide and alkylidene-trans-alkene halide; (3) either (i) treating either the mixture of the alkylidene alkene halide isomers or the alkylidene transalkene halide with a metal such as magnesium, thereby forming an organometallic reagent is, and reaction of the organometallic reagent thus formed with a trialkyl-ortho-formate (with formation an acetal, which is then hydrolyzed with acid) to obtain the desired alkylidene-trans-alkenal or (ii) Implementation of the mixture of alkylidene-alkene-halide isomers with an alkyllithium compound to form a second organometallic reagent (mixture of

509808/1085

Isomers) and then reaction of the organometallic reagent with a dialky! Formamide and the following Acid hydrolysis with the formation of a mixture of 2-alkylidene-3-cis-alkenal and alkylidene = -3-trans ~ -alkenal or (iii) physical separation of the alkylidene-cis-alkehhalide from the alkylidene-trans-alkene halide and then independent Reaction of each isomer with an alkyllithium compound to form a second organometallic Reagent and then implementation of the second orga- * non-metallic reagent with dialkylformamide and then · »· low acid hydrolysis, producing an alkylidene-fcrans-alkenal and an alkylidene-cis-alkenal can be obtained separately.

The 2-alkylidene-3-alkenals obtained by the processes described are useful, among other things, for changing the organoleptic properties of consumer goods.

The 2-alkylidene ~ 3-alkene isomers produced here correspond to essentially of the formula

wherein R _{1 represents} a lower alkyl group and one of R ₃ and R 1 is hydrogen and the other is lower alkyl. For the aforementioned usability of the alkenals

809808/1085

I I I

Lower alkyl groups containing 1 to 4 carbon atoms are desirable, and in certain preferred embodiments of the invention, R _{1 is} methyl or ethyl and .R, or R- is methyl, ethyl, isopropyl, η-butyl and 2 '-methylpropyl.

The invention also produces new 2-alkylidene-3-alkenals which are used for changing the organoleptic properties can be used by consumer goods. The new compounds are 2-alkylidene-3-alkenals of the formula

wherein a represents at R and R2 is hydrogen and DASL other is methyl, and one with R ₃ and R. is hydrogen and the other is an alkyl group having 2 or 4 carbon atoms.

Thus, the alkyl groups of the new compounds contemplated according to the invention represent lower alkyl groups. Preferably, the alkyl groups represented by R ₃ and R. are ethyl or isobutyl groups.

509808/1085

The description shows that several "cis-trans" isomers due to the presence of alkyl substituents on the carbon atoms surrounding the carbon-carbon double bond of the "alkenal" chain (as opposed to the "alkylidene" group) are possible and should be considered here. For example, a particularly preferred alkenal is 2-ethylidene-cis-3-hexenal, the compound of the above formula _{satisfying when R 1 is} methyl, R _{3 is} ethyl and R is hydrogen. The structure of this compound can be given as follows:

In this configuration, the _{methyl group represented by R 1} is trans to the carbonyl group and the _{ethyl group represented by R 3 is} cis to the alkylidene group. The processes according to the invention primarily produce compounds in which the _{alkyl group represented by R 1 is} in a position trans to the carbonyl group.

It is therefore apparent from the present description that the position of the R ₃ and R substituents in the formula

509808/1085

is similarly significant.

The trans-2-ethylidene-cis-3-hexenal:

has a citrus, albedo-like character, the it is ideally suited for use in citrus flavors and especially in orange flavors or aromas power. It gives orange drinks a juicy character and improves the sweetness. 2-ethylidene-6-methyl-cis-3-heptenal (primarily trans-2-ethylidene-6-methylcis-3-heptenal):

has a green, flowery, slightly cucumber-like top fragrance with a twig-like undertone that makes' it special

509808/1085

makes it suitable for use in fragrance compositions. Trans-2-ethylidene-trans-3-hexenal:

has an odor which is noticeably different from the trans-2-ethylidene-cis-3-hexenal material described above, because it has a bit more of a mustard-like, coarser shade.

Cis-2-ethylidene-cis-3-hexenal:

in a mixture with trans-2-ethylidene-cis-3-hexenal and the Diethylacetal of cis-2-ftthyliden-cis-3-hexenal in the following ratio:

cis-2-ethylidene-cis-3-hexenal 70% trans-2-ethylidene-cis-3-hexenal 20%

Diethylacetal of cis-2-Kthylidencis-3-hexanl 10%

at 0.5 ppm give an orange juice aroma a "juicier ¹¹ note. The taste is dominated by fresh green

509808/1085

_M R _

Notes with light, spicy undertones. He has a delicate, green, branch-like, leaf-like, fruity Aroma note with a natural note of cinnamon when it dries out.

The 2-alkylidene-3-alkenal derivatives according to the invention and mixtures thereof can be used to change, vary, reinforce, Modification, favoring or other improvement of the organoleptic properties including the taste and / or aroma of a wide variety of materials that are digested, consumed or consumed or are sensed organoleptically in some other way. The term "change" in their various Forms here is the delivery or bestowal of a flavor character or a flavor note for a otherwise mild, relatively tasteless substance or the augmentation of an existing taste characteristic, if the natural taste is not satisfied in a certain respect or the addition of the present taste or aroma impression to modify the organoleptic Of character. The materials that are changed in this way are generally referred to here as "consumer goods" or "consumer materials" designated.

The starting material used here represents an Ov / -, ßunsaturated Aldehyde of the formula

JQ H

509808/1085

represents, wherein R. has the meaning given above. This aldehyde is reacted with a halogen either under anhydrous conditions or in the presence of water. The halogens that can be used include chlorine, bromine and iodine, with chlorine and bromine being preferred.

The halogen can be added in any convenient manner depending on its physical state. Therefore chlorine can be blown in the gaseous state into an aqueous solution or dispersion of the aldehyde. bromine can be added in the form of a liquid, the addition preferably taking place slowly; this addition can, for example done drop by drop.

The initial addition can be at a relatively low temperature take place depending on the respective halogen to moderate and control the conversion rate. After that the temperature is gradually increased in the range of about 70 to about 100 ° C in order to have a good complete flow of the Ensure response. In some embodiments of the invention it is preferred to reflux the aqueous mixture to heat. The reaction times required vary with the halogen used, the type of its addition, the temperature, the particular reagent and the reaction carrier. In general, it is preferred to do this Carry out the reaction for a period of about 1 to about 10 hours.

The resulting halogen derivative has the formula

- 10 -

509808/1085

wherein X represents a halogen atom such as a bromine or chlorine atom. The halogen derivative can, if desired, cleaned and isolated in the manner indicated here.

This halogen derivative is then used to produce the alkylidene-alkene halide the formula

used, wherein R ₁ , R ₃ , R. and X have the meaning given above. This halogen derivative can either by (i) an alkenylation reaction with a suitable alkenylating agent, such as, for example, a trisubstituted alkylidenephosphorane or an alkylidenephosphoric triamide, or by (ii) using an alkylating agent, such as an alkylmagnesium halide Grignard reagent and subsequent hydrolysis to form a hydroxy-haloalkene :

OH

509808/1085 * ¹¹ '

and subsequent Ie dehydration of the hydroxyhaloalkene are obtained. When the halogen derivative is obtained by employing the alkenylation reaction, ie, step (i), a mixture of alkylidene-cis-alkene halide and alkylidene-trans-alkene halide is produced. However, the ratio of cis to trans isomers at this stage can be predetermined depending on the solvent used. For example, when using a trisubstituted ethylidenephosphorane in a hexane solvent, the ratio of cis isomers to trans isomers is 7: 3. On the other hand, when the alkenylation reaction is carried out starting from the alkyl magnesium halide Grignard reagent, the alkylidene alkene halide formed after the dehydration reaction is essentially all alkylidene transalkene halide. In the foregoing, the terms "cis" and "trans" are referred to applied to R ^ or R ₄ as an alkyl group on one side of the double bond and the ethylidene group on the other side of the double bond.

The way using the Grignard connection makes use of itself using a compound of the formula:

^R 3

^N Mg X ¹

^R 4

wherein X ^{1 represents} a bromine or chlorine group and R ₃ and R _{4 have} the above meaning. The reaction with the Grignard reagent is carried out in a reaction vehicle such as a solvent for the halogen compound.

509808/1085

- 12 -

Such carriers or vehicles include aliphatic or aliphatic
cyclic ether compounds such as diethyl ether, tetrahydrofuran, "Glyme" ethylene glycol dimethyl ether, "diglyme" diethylene glycol dimethyl ether and the like. The temperatures used may range from -10 ° C up to about 100 ⁰ C.
lie. Temperatures in the range from 15 to 30 ° C. are preferred.

The reaction time at such temperatures can range from 10 minutes to about 2 hours. However, the time depends on the temperature, the carrier, the particular reactants and the rate at which the reacting materials are used be combined.

The initial reaction with the Grignard reagent gives
a connection of the structure:

^N * - O Mg X ¹

Upon hydrolysis with a dilute mineral acid such as dilute hydrochloric acid or dilute sulfuric acid or with an acid salt such as ammonium chloride, the corresponding hydroxyl compound is formed. This resulting hydroxyl derivative is then converted to the alkene halide
Treatment at relatively high temperatures with a strong dehydrating agent such as an alkali metal bisulfate or oxides such as aluminum oxide, silicon dioxide

509808/1085

- 13 -

and the like are dehydrated. The bisulfate dehydration is performed with an alkali metal salt such as sodium or potassium bisulfate. Potassium bisulfate is a preferred one Bisulfate.

The bisulfate dehydration reaction occurs as a melt carried out at temperatures of the order of magnitude from about 200 to about 250 ° C., with temperatures from 210 to 225 ° C are preferred.

DieDehydratisierung can be performed to about 40O ⁰ C by guiding the hydroxy compound on an oxide at temperatures of about the 200th Preferred oxides include silica, alumina and the like. In each case the product obtained is the 1-alkylidene-ihalo-2-alkene.

The alternative route to the alkylidene haloalkene (where however the mixture of cis and trans isomers is formed) represents the route via a phosphorus compound. The phosphorus compounds used here are either aliphatic Alkylidene trialkyl or triaryl substituted phosphoranes the formula

f ρ

^R 5

where R _{5 is} aryl, preferably phenyl, or alkyl, preferably lower alkyl having 2 to 4 carbon atoms, and R ^{1 is} the alkyl group represented by R _{3 or R.}

509808/1085

- 14 -

an alkylidenephosphoric triamide of the formula

P - NR ₆ R ₇

NI

^R 4 ^NR 6 ^R 7

represents wherein R-, and R. are as defined above

j 4

and Rg and R ₇ when viewed alone. Mean alkyl or when taken together mean alkylidene.

The reaction of the o-haloaldehyde and the phosphorus compound is desirably carried out in the presence of a reaction carrier which is useful for modification and control the course of the reaction is used. Preferred carriers include aliphatic or cyclic ethers or alicyclic, acyclic or aromatic hydrocarbons containing from 5 to 10 carbon atoms. Thus, preferred include Solvents diethyl ether, tetrahydrofuran, benzene, toluene, hexane and the like. The reaction becomes desirable carried out at temperatures between -1O and 100 ° C. In certain, particularly preferred embodiments of the invention, temperatures from about 20 to about 30 C applied. The solvent used determines the cis-trans ratio. Thus, the use of a hexane solvent results a cis-trans isomer molar ratio of 7: 3.

Regardless of which alkenylation route is used, the intermediate produced is always a Λ -alkylidene-1-

509808/1085

- 15 -

halogen-2-alkene of the structure:

This alkylidene haloalkene is converted into the 2-alkylidene-3-alkenal converted by means of one of the two reaction sequences:

1. The 1-alkylidene-i-halogen-2-alkene is combined with magnesium reacted to form a Grignard reagent that has the structure:

This Grignard reagent is then combined with a trialkyl orthoformate reacted (whereby an acetal is formed, which is then hydrolyzed in acid), whereby only 2-alkylidene-trans-3-alkenal is formed.

2. The 1-alkylidene-i-haloalkene is mixed with an alkyl alkali metal compound, such as n-butyllithium, reacted, whereby the 1-alkylidene-1-lithio-2-alkene of the following Structure is formed.

509808/1085

The i-alkylidene-i-lithio-2-alkene thus formed is then followed with a di-lower alkylformamide ( from acid hydrolysis), such as dimethylformamide, implemented. Before the reaction with the n-butyllithium or the like may include the 1-alkylidene-i-halo-2-cis-alkene and 1-alkylidene-1-halo-2-trans-alkene are separated by distillation. When the cis and trans isomers so separated, the resulting product separately represents 2-alkylidene-cis-3-alkenal and 2-alkylidene-trans-3-alkenal On the other hand, if the cis and trans isomers are not so separated, it would turn out to be resulting product is a mixture of 2-alkylidene-cis-3-alkenal and 2-alkylidene-trans-3-alkenal.

In reaction sequence (1), the alkadienyl magnesium halide is prepared by adding metallic magnesium to the reaction medium in an amount desirably at least equimolar to that of the alkylidene haloalkene. The treatment with magnesium is carried out at temperatures in the range from about 20 to ^100.degree. C. and preferably 35 to 80.degree. The reaction is effected in an inert reaction carrier, aliphatic or cyclic ethers being desirable. Examples of such preferred carriers are tetrahydrofuran, "glyme", "diglyme" and the like.

- 17 -

509808/1085

In reaction sequence (1), too, the reaction with the tri-lower alkyl orthoformate is carried out under reflux conditions in, preferably, the same solvent that was used in the original Grignard reaction was applied, carried out, Therefore, if tetrahydrofuran was used as a solvent in the original Grignard reaction, the reaction becomes of the Grignard reagent with the tri-lower alkyl orthoformate (whereby an acetal is formed which then hydrolyzed in acid), also conveniently in the same solvent, tetrahydrofuran. The applied Orthoformates are desirably lower alkyl orthoformates, wherein the alkyl groups have 1 to about 4 carbon atoms. A preferred orthoformate represents ethyl orthoformate (triethoxymethane). In this Reaction sequence (1) is only the 2-alkylidene-trans-3-alkenal obtain.

In reaction sequence (2) the H-alkylidene-i-lithio-2-alkene becomes by adding an alkyl alkali metal compound such as n-Butyllithium to the 1-alkylidene-1-halo-2-alkene manufactured. Optionally, before such an addition, the cis and trans isomers, the 1-alkylidene-1-halo-trans-2-alkene and the 1-alkylidene-i-halocis-2-alkene be separated by distillation = the alkali metal used in the alkyl alkali metal compound can represent either lithium, sodium or potassium, with lithium being the preferred alkali metal. It is desirable that the alkyl group has 3 to 6 carbon atoms contains, such as the n-butyl group. Therefore makes n-butyllithium the preferred agent for conversion of the alkylidene halogen alkene to 1-alkylidene-1-lithio-2-alkene

- 18 -

509808/1085

The following solvents can be used in the formation of the i-alkylidene-i-lithio-2-alkene: diethyl ether, tetrahydrofuran, "glyme" and "diglyme" and other aliphatic or cyclic ethers. The reaction is conducted at temperatures ranging from about -30 ° C to + 5O ⁰ C carried out, the range is preferably from -15 to ⁰ ° C. The reaction of the 1-alkylidene-1-lithio-2-alkene with the di-lower alkyl formamide is effected in the same solvent at temperatures in the range of -5 to +15 ⁰ C, with the range from 0 to 1O ° C is preferred. As stated above, if the cis and trans isomers of 1-alkylidene-1-halo-2-alkene are not separated in this reaction sequence (2), the resulting product, the 2-alkylidene-3-alkenals, in the form of a mixture of the cis and trans isomers.

The pressure in each stage of the reaction sequence (1) and (2) can vary over a range from sub-atmospheric to super-atmospheric pressures. For the sake of convenience and for economy, it is preferred to run the reaction at substantially atmospheric pressures.

The intermediate and / or end products obtained can by conventional cleaning after appropriate washing, neutralization and / or drying as required or be isolated. Therefore, such products can be processed by distillation, steam distillation, vacuum distillation, Extraction, crystallization, preparative chromatographic techniques and the like can be purified and / or isolated.

The 2-alkylidene-alkenals according to the invention can easily

509808/1085

by reacting an alkylmetalloacetylide with a pialkoxyacetonitrile to form an imine salt, hydrolysis of the imine salt to form 1,1-dialkoxy-3-alkyn-2-one, Treatment of the 1,1-dialkoxy-3-alkyn-2-one with an alkylidene triphenylphosphorane, hydrolysis of the resultant 1,1-Dialkoxy-2-alkylidene-3-alkynes in acidic aqueous solution with formation of 2-alkylene-3-alkynal and reduction the triple bond to a double bond can be generated by hydrogenation to obtain the new 2-alkylidene-3-alkenal.

It is significant that the hydrogenation of the 1,1-dialkoxy " alkyn-2-ons primarily the 1,1-dialkoxy-cis-3-alken-2-one isomer results, which then to the 1,1-dialkoxy-trans-3-alken-2-one using a suitable cis-trans isomerization reagent, such as a mixture of acetic acid and sodium iodide or potassium iodide (preferred concentration range of alkali metal iodide isomerized in acetic acid from 0.5 to 2% by weight) will. It is further noted that the hydrolysis of the 1,1-dialkoxy-2-alkylidene-trans-3-alkenal, which as a result the reaction of the trisubstituted alkylidenephosphorane with the 1,1-dialkoxy-3-trans-alken-2-one is a mixture of cis-2-alkylidene-trans-3-alkenal and trans-2-alkylidene-trans-3-alkenal results. The cis-2-alkylidene-trans-3-alkenal in the mixture can then be specific to the trans-2-alkylidene-trans-3-alkenal (creating a material that contains only one isomer, namely: trans-2-alkylidene trans-3-alkenal) by means of a suitable cis-trans isomerization agent, such as a mixture of acetic acid and an alkali metal iodide, such as sodium iodide or Potassium iodide, specifically to be isomerized.

- 20 -

509808/1065

From the present description it can be seen that the connections produced according to the given description can be used to alter the organoleptic properties of a wide variety of consumables. These materials include foods, perfumes, fragrances, and tobacco products. The after the procedure Compounds generated can be added directly to the consumption materials or the addition can be in the form of taste or flavor. Spices or perfume compositions depending on the consumed material used. The compounds can be at a stage of the manufacture of the consumable material to obtain optimal results based on the equipment used, process techniques, end use and the like can be added.

The following examples illustrate embodiments of the invention which it is presently preferred to practice. These Examples are not intended to be limiting.

Example I. Production of egg »-chlorocrotonaldehyde

In a 1 liter three-necked flask equipped with a reflux condenser, mechanical stirrer, thermometer, Y-tube and chlorine inlet tube, 300 ml of water and 70 g of anhydrous crotonaldehyde are added. The contents are cooled to 8 ° C. and 82 g of chlorine are blown in over a period of 3 hours, the reaction temperature being kept ^{between 7 and 11 ° C.} The reaction mass will

- 21 509808/1085

then heated to reflux (99-1OO ° C) over a period of 2 hours. The reaction mass represents a two-phase system at this point: an oil phase and an aqueous phase.

The aqueous phase is mixed with 200 ml portions of chloroform extracted. The chloroform extract is combined with the organic phase and the combined material replaced by 5 g anhydrous sodium sulfate filtered = the filtrate is over 15g of anhydrous sodium sulfate and dried with 30 ml Washed with chloroform. The chloroform is evaporated to give 104 g of raw material which is passed through a 30 cm Vigreaux column is distilled at 141 to 147 ° C steam temperature and atmospheric pressure, where (λ / -Chlor er ο tonaldehyd is obtained in 74.5% yield (known Procedure).

Example II Production of cis- and trans-3 ° -chloro-4-hydroxy-2-heptane

In a 500 ml three-necked flask fitted with a reflux condenser, mechanical stirrer, calcium chloride drying tube, thermometer, input funnel and a Y-tube 9.6 g of magnesium turnings and 30 ml of anhydrous diethyl ether are added. 3 drops of a solution of 50 g 2-bromopropane in 100 ml of diethyl ether was added to the magnesium-diethyl ether mixture with stirring. If the Reaction has started, which is documented by an increase in temperature, the rest of the 2-bromopropane ether

- 22 509808/1085

Mixture added at a rate that is at reflux holds.

After the addition is complete, the reaction mass is stirred for a period of 1 hour at room temperature, wherein at the end of this period the magnesium chips are completely used up. A solution of 32 g of C ^ -chlorocrotonaldehyde in 70 ml of diethyl ether is added dropwise to the flask at a rate equivalent to gentle reflux holds. The reaction mass is stirred for 1 hour at room temperature and then to 5 ° C using a Cooled ice water bath.

A saturated ammonium chloride solution (100 ml) is added dropwise to the reaction mass with stirring while the pot temperature is kept just below 25 ° C. After decanting the organic phase from the resulting thick precipitate, a solution of 110 ml of 10% aqueous sulfuric acid is added to the precipitate. The resulting aqueous solution is extracted using 2 100 ml portions of diethyl ether and the extracts are added to the original organic solution. After the diethyl ether solution has been dried over 35 g of anhydrous sodium sulfate, the solution is concentrated in vacuo in a rotary evaporator to give 32.7 g of a yellow liquid.

The liquid is distilled in vacuo through a semi-micro Vigreaux column equipped with a variable reflux head. The product, its structure by MS (mass spectroscopy), IR (infrared spectroscopy) and NMR

- 23 -

509808/1085

(nuclear magnetic resonance spectroscopy) analyzes confirmed represents 3-chloro-4-hydroxy-2-heptene, which at 72 bis 75 ° C and 8 mmHg pressure distilled.

Example III

Production of 3-chloro-2,4-heptadiene from 3 ° chloro-4-hydroxy-2-heptene

A 25 ml three-necked semi-micro reaction flask marked with egg "» eat Equipped with a distillation head, a receiving cap and an oil bath is charged with 3.0 g of molten potassium sulfate. The potassium disulfate is obtained by heating the oil bath to 220 ° C melted and there are 5.5 g of geraäss Example II produced 3-chloro-4-hydroxy = -2 ~ heptens dropwise during added over a period of 15 minutes "

During the addition, the product distills off from the reaction mixture. Redistillation gives two isomers of 3-chloro-2,4-heptadiene _f , which boil at 140 to 143 ° C at atmospheric pressure. The MaR, MS and IR data confirm that the structure of the resulting compound is 3-chloro-2,4-heptadiene ". It is believed that" the cis and trans isomers of 3-chloro = 2 _f , 4-heptadiene are present »

Example IV

Production of e is ° and trans ° -3 ° chlorine ° 2 (, 4 ° -hept "adien from Φ -Chlorcrotonaläehyd

/ 1085 - 24 -

1000 ml of anhydrous diethyl ether and 82.5 g of triphenylphosphine salt of 1-bromopropane are charged to a 2-liter, three-necked round-bottomed flask, which is equipped with an addition funnel, mechanical stirrer, pot thermometer, nitrogen inlet and a Vigreaux column with calcium chloride drying tube, and it 85 ml of a 2.43 molar solution of methyllithium in ether are added over 12 minutes, while a temperature between 14 and 18 ° C is maintained. After the addition is complete, 900 ml of ether are removed by distillation and the addition of a solution of 21.7 g of Φ -chlorocrotonaldehyde in 200 ml of ether is started. The addition results in a thick slurry / which is made more fluid by adding another 200 ml of ether.

After refluxing for 4 hours, cool the reaction mixture and remove the solid material by filtration removed. The concentration of the filtrate results in 9 g of a semi-solid material, which after digestion with two 200 ml portions of pentane and subsequent solvent removal 3.3 g of crude cis and trans-3-chloro-2-heptadiene results.

Example V

Preparation of 2-ethylidene-trans-3-hexenal using the Grignard reagent of 3-chloro-2-cis-4-heptadiene and of 3-chloro r-2-trans-4-heptadiene.

A 25 ml three-necked tube fitted with a thermometer, reflux condenser, magnetic stirrer and potassium chloride drying tube

509808/1085

The round bottom flask is filled with 0.5 ml of anhydrous tetrahydrofuran, 0.41 g of magnesium shavings and 2 drops of ethylene bromide are charged. After 30 minutes, 3 drops of 3-chloro-2,4-heptadiene are added added to the reaction mass. The reaction mass is heated to reflux in about 1 hour.

After a further 1/2 hour 1.5 g of 3-chloro-2,4-heptadiene are added and the reaction mass is during held at reflux for a period of 5 hours, wherein during this time 2 drops of ethylene bromide are added.

At the end of the 5 hour period, 1.71 g of ethyl orthoformate are obtained added, the temperature of the reaction mass between 60 and 70 ° C is maintained. The reaction mass will then refluxed for 20 minutes and refrigerated overnight. The pH of the mixture is adjusted to 1 by adding of 3.2 g of a 6% aqueous hydrochloric acid solution.

The reaction mass separates into two phases, an aqueous and an oil phase. The aqueous phase is made with two 3 ml portions Ether extracted. The ether extracts are combined with the oil layer and the resulting material becomes successively with 0.5 ml of saturated aqueous sodium chloride, 0.5 ml of saturated aqueous sodium chloride, 0.5 ml of saturated aqueous sodium bicarbonate and 0.5 ml saturated aqueous sodium chloride. The washed ethereal solution is filtered through anhydrous sodium sulfate and concentrated on a rotary evaporator to give 1.2 g of material. The 2-ethylidene-trans-3-hexenal is determined by preparative GLC (5% Carbowax 20 M polyoxyethylene glycol

- 26 509808/1085

Chromasorb G aluminum oxide, 2.44 m χ 6.4 mm column) isolated.

The 2-A "thylidene-trans-3-hexenal structure is determined by IR, NMR and MS analyzes confirmed. ·

Example Vl Production of oi-bromocrotonaldehyde

One with Y-tube, calcium drying tube, pot thermometer, addition funnel 1000 ml three-necked round bottom flask equipped with a mechanical stirrer is charged with 100 g of crotonaldehyde and 229 g of bromine are added over a period of 1 1/2 hours, the temperature of the contents of the flask is kept between -10 and 2 ° C. 142 g finely powdered Sodium acetate is added to the reaction mass over 20 minutes and the mass is then maintained on hold the pot temperature between 15 and 30 ° C stirred. The reaction mass is then used for 40 minutes a Friedrich condenser and a 25Ο ml three-necked receiving flask steam distilled to give 147.2 g of a yellow oil.

The oil is saturated with four 25 ml servings aqueous sodium bicarbonate solution and then dried over anhydrous potassium chloride. The resulting Material is with a 30 cm Vigreaux column at a temperature of 75 to 76 ° C and at 30 mmHg to obtain oL »-Bromer ο tona ldehyde distilled.

- 27 -

509808/10 85

Example VII

Preparation of a mixture of 3-bromo-2-cis-4-heptadiene and 3-bromo-2-trans-4-heptadiene

One with a mechanical stirrer, pot thermometer, nitrogen 3000 ml three-necked round flask fitted with a fine inlet tube and addition funnel is charged with 1100 ml of anhydrous benzene and 180 g of triphenylphosphine salt of 1-bromopropane and 205 ml of a (2.34 m) solution of butyllithium in hexane are added over the course of 1 hour, the reactant mass is kept under nitrogen. A deep red orange slurry is obtained. A solution of 65 gC ^ -Bromocrotonaldehyde in 100 ml of anhydrous benzene is added to the reaction mass for 1 hour to give a whitish brown Solution added.

The reaction mass is then heated to 50 ° C with stirring and at 50 to 55 ° C for a period of Held for 1 hour. The reaction mass is filtered to give a benzene solution and a white precipitate will. The precipitate is washed with an additional 100 ml of benzene. The benzene solution and the benzene wash solution are combined, the benzene is evaporated and the resulting 85.3 g of oil is passed through a 5 × 80 cm column, the was filled with alumina, chromatographed. The 80 g Chromatographed oils are stored at 74 to 78.5 ° C (35 to 38

Hg pressure) to give a 57% yield of 3-bromo-2-cis-4-heptadiene and 3-bromo-2-trans-4-heptadiene (cis: trans ratio 7: 3) distilled. The structures of the above named compounds were determined by NMR, IR and MS analyzes confirmed.

509808/1085 -28-

Example VIII

Separation of 3-bromo-2-cis- and trans-4-heptadiene

A mixture of 3-bromo-2-cis- and -trans-4-heptadiene becomes through a 2.5 χ 15 cm, filled with 6.2 mm Raschig rings Column to obtain 23.7 g of a material which, according to GLC, is 67% ice and 31% 3-bromo-2-trans-4-heptadiene, which boils between 75 and 78 ° C and 38 Torr and 2.4 g of a material which, according to GLC, is 15% cis- and is 85% 3-bromo-2-trans-4-heptadiene, distilled.

Example IX

Preparation of 2-ethylidene-trans-3-hexenal from 3-bromo-2-cis-4-heptadiene

A 50 ml three-necked round bottom flask which has been purged with nitrogen and is fitted with a reflux condenser equipped with a calcium chloride dry tube, a magnetic stirrer, a pot thermometer and a nitrogen inlet tube is charged with 1.04 g of magnesium turnings and 8 ml of tetrahydrofuran and then 0 _f 2 cm of 2-bromo-2-cis-4-heptadiene are added to initiate the reaction, the reaction mass being kept at a temperature of 42 to 45 ° C. Additional tetrahydrofuran (2 ml) is added to the reaction mass. A solution of 3.2 g of 3-bromo-2,4-heptadiene in 5 ml of dry tetrahydrofuran is then added to the reaction mass over 1 hour, the reaction mass being kept at 40 to 45 ° C.

509808/1085 - 29 -

After 2 hours, 4.67 g of ethyl orthformate are added to the reaction mass over a period of 25 minutes, the pot temperature is kept between 37 and 48 C. The reaction mass then refluxes heated and held at reflux for 45 minutes. The reaction mass is then cooled and turns a dark amber color Solution decanted from the unreacted magnesium. The tetrahydrofuran is obtained from the solution evaporated from 11.9 g of a viscous amber-colored oil. A 6% aqueous hydrochloric acid solution is added to the oil (14.4 g) added and two phases form. After separation, the aqueous phase is mixed with two 5 cm portions Ether, which are combined with the organic layer. The combined organic layer will successively with 1.5 ml of saturated aqueous sodium bicarbonate solution and 1.5 ml of saturated aqueous sodium chloride washed, dried over anhydrous sodium sulfate, and concentrated to give 1.5 g of an amber oil. By preparative GLC using a 5% Carbowax column on Chromosorb G (SE-30 "column-100 °, 4 ° / min.) cis-2-ethylidene-trans-3-heptenal is obtained, the structure of which is confirmed by MS, GLC and NMR analyzes.

Example X

Preparation of 2-ethylidene-cis-3-hexenal from 3-bromo-2-cis-4-heptadiene

In one with a magnetic stirrer, thermometer, calcium chloride drying tube and nitrogen inlet tube equipped 100 ml

- 30 .509808 / 1085

Three neck round bottom flask becomes a solution of 2.0 g of 3-bromo-2-cis-4-heptadiene entered in 20 ml of anhydrous diethyl ether and 5.4 ml of n-butyllithium (2.34 m in hexane) added in 2 minutes, the pot temperature up -1O ° C is maintained. The reaction mass then becomes clear yellow over a period of 3 hours Solution stirred.

The reaction mass is then placed in a second dry 100 ml three-necked round bottom flask containing 1.25 g of dimethylformamide and Contains 2O ml of anhydrous ether, entered. The clear yellow solution becomes cloudy and a white solid precipitates out. Of the The temperature range is 0 to 9 ° C during the 2 minute addition.

The reaction mass is then stirred and warmed to room temperature over a period of half an hour and 30 ml of 0.5 η aqueous hydrochloric acid are added to dissolve the precipitate. The reaction mass separates into two layers, an ether layer and an aqueous layer, 'on. After separation, the ether layer becomes washed with 5 ml of saturated aqueous sodium bicarbonate solution, dried over anhydrous sodium sulfate and concentrated to obtain 1.4 g of a yellow oil.

By preparative GLC separation on a 2.44 m χ 6.44 mm (8 ¹ χ 1/4 ") column filled with 5% Carbowax (SE-30 column, 100 ° C, 4 ° / min.), 2- Ethylidene-cis-3-hexenal, the structure of which is confirmed by NMR, IR and MS analyzes, The material is distilled at 27 to 33 ° C and 4 to 5.8 mmHg pressure.

509808/1085 " ³¹

Example XI

2-ethylidene-trans-3-hexenal from 3-bromo-2-trans-4 * ' heptadiene

One with addition funnel, thermometer, calcium chloride drying tube and magnetic stirrer equipped 250 ml three-necked flask is mixed with 5.45 g of 3-bromo-2,4-heptadiene (4-cis / 4-trans ratio 15:85) and charged 55 ml of ether. The reaction mass is cooled to -15 ° C and 14.6 ml of a 2.34 M solution of butyllithium in hexane are added over 30 minutes. The reaction mixture is left to stand at +3 to -5 ° C. for 5 hours.

The reaction mixture is transferred to a flask containing Contains 3.41 g of dimethylformamide in 40 ml of ether, which had previously been cooled to -10 ° C. After standing for 20 minutes 35 ml of a 4% aqueous hydrochloric acid are added Receipt of two phases added. The aqueous layer is diluted to 75 ml with water and extracted with 20 ml of ether. The ether extract and the organic phase are combined, washed with saturated sodium bicarbonate solution (10 ml) and dried with sodium sulfate. By removing the ether, 4.9 g of oil are obtained. By column chromatography over 98 g of silica with hexane / hexane: ether, 0.16 g of 2-ethylidene-trans-3-hexenal are obtained. By MS, NMR and The structure is confirmed by IR analysis.

. - 32 -

509808/1085

Example XII Production of 2-ethylidene-cis-3-hexenal

(i) Preparation of 1,1-dimethoxy-3-hexyn-2-one

An ether solution of ethyl magnesium bromide is produced from 7.3 g of magnesium shavings and 32.7 g of ethyl bromide. About 20 g of ethyl acetylene are admitted as gas under a dry ice condenser and the mixture is refluxed for 2 hours until the evolution of gas has ceased. The mixture is then on, cooled to 0 ⁰ C and there are added 30.2 g Dimethoxyacetonitril in ether solution.

The mixture is allowed to rise to room temperature and stirred for 2 hours, the lower layer of the Two-phase mixture becomes almost solid during this time. The mixture is cooled again and washed with 16 ml of sulfuric acid, which is diluted with 300 ml of water, treated. The layers are separated and the organic layer becomes successive with saturated aqueous sodium chloride solution and saturated aqueous sodium bicarbonate solution and then dried over 4A molecular sieves. By removing the Solvent 35.3 g of a yellow oil in 99% purity (determined by GLC / gas-liquid phase chromatography7) obtain.

(ii) Preparation of 2-ethylidene-3- hexylal dimethylacetal

Ethyltriphenylphosphonium bromide (24.8 g) is stirred with 100 ml of benzene and there are 40 ml (1.6N) of butyllithium added in hexane over about half an hour, with

509808/1085 " ³³

a water bath is used to absorb the low heat of reaction. The mixture (light orange) is at room temperature Stirred for 0.7 5 hours and there are 10.0 g of 1,1-dimethoxy-3-hexyn-2-one dropwise in the course of a added half an hour.

After an additional 15 minutes at 40 ° C (water bath), the mixture is filtered and passed through a under reduced pressure Fractionation column evaporated. The residue is dissolved in isopentane, filtered, and again to give 4.3 g of a yellow-orange oil evaporated. It is determined by gas chromatography, mass spectroscopy (NMR) that the main peaks represent isomers of the desired structure:

(iii) Preparation of 2-ethylidene-3-hexynal

The acetal isomers produced in this way are dissolved in 50 ml of ether dissolved and mixed with 25 ml of water for 1 1/2 hours

509808/1085 ³⁴ "

Contains 2.5 g of oxalic acid (room temperature), stirred. the Layers are separated and washed successively with saturated aqueous sodium carbonate solution and brine and vaporized at atmospheric pressure through a Vigreaux column. After removing the last traces of the Solvent in vacuo leaves 3.0 g of a reddish oil. It is confirmed by GC-MS and NMR that the main product Represents 2-ethylene-3-hexynal.

(iv) Production of 2-ethylidene-cis-3-hexenal -

The 2-ethylidene-3-hexenal (2.5 g) thus produced is dissolved in 20 ml of hexane and a small amount of solid is removed by filtration through a bed of neutral alumina. The solution is then with 0.25 g Lindlar catalyst (palladium on potassium carbonate, poisoned with lead acetate) mixed and under hydrogen gas stirred at a pressure of about 1 atmosphere for 6 1/2 hours. The resulting mixture is filtered and the Solvent removed by a Vigreaux column. The main component that is made up of a Carbowax (polyethylene glycol) filled GLC column is obtained according to IR, NMR and MS spectra:

The other 2-alkylidene-3-alkenals according to the invention are prepared in a similar manner.

- 35 509808/1085

In the following NMR spectra, the shifts measured in ppm relative to a tetramethylsilane standard in carbon tetrachloride at TOO MHz. The 2-ethylidene-cis-3-hexenal, which is generated according to example XII shows the following spectrum:

Shift number of proton peak assignment

0.02 3 triplet CH ₃ -CH ₃ -

1.88 doublet CH ^ -C = C-C = O

1.92-1.70 multiplet CH ₃ -CH ₂ -C = C _-

5.75 2 multiplet olefinic

Protons

6.61 1 quartet CH ₃ -CH = CC = O

9.41 1 singlet formyl proton

Example XIII

10 1 Orange juice concentrated to an aqueous essence by Libby, McNeil & Libby Corporation of Ocala, Florida was extracted with diethyl ether in a Quickfit multipurpose extractor. After drying the ether extract with anhydrous Magnppiurosulfate the extract is in a Kuderna-Danish device and by GLC and GLC / MS analyzes analyzed using a 5750 Chranatograph with a flair ionization detector was equipped and operated under the following conditions: carrier gas; helium

Flow rate 40 ml / min.

Pick-up speed: 6.4 mm / min. (0.25 "/ min)

509808/1085

- 36 -

Detector: F.I.D. at 250 ° C

Column: 3.05 m χ 3.2 mm (10 ¹ χ 1/8 ")

O.D. 25% Carbowax 20M on 60/80 mesh DMCS treated Chromosorb WAW

Program speed: 50-225 ° C at 2 ° / min.

The GLC / MS system used had the following components on:

GLC: Aerograph 1520

Detector: F.I.D. at 200 ° C

Column: carrier-coated

Carbowax 20M, 0.02 I.D.

Program speed: room temperature to 175 ° C

at 2 / min.

Distribution of discharge: 6: 1 according to MS

MS: Hitachi RMU 6E, equipped

with a Watson-Biemann separator in the MS oven, the rapid exposure spectra of compounds separated by chromatography.

These compounds, which only give weak mass spectra, are collected on a semi-preparative scale under the following conditions:

GLC: F&M 700

Detector: T.C. at 250 ° C

Carrier gas: helium

Flow rate: 80 ml / min.

Column: 2.44 m χ 6.44 mm (8 1/4 ")

O.D. 25% Carbowax 20 M on 6Ο / 8Ο mesh Cromosorb WAW

Program speed: 75-225 ° C at 2 ° / min 509808/1085

- 37 -

Compounds collected from the orange juice extract that were not identified by GLC / MS spectra were subjected to NMR and IR analysis for further structure elucidation.

A specific compound that was obtained is an unsaturated aldehyde with a molecular weight of 124. The elemental formula is _{determined by high-resolution mass spectroscopy as CgH 10} O, and UV (ultraviolet) spectral analysis shows that the compound is a monosubstituted o ^ -ß- represents unsaturated aldehyde. An NMR spectrum is recorded and these results together with the full mass spectrum show that the compound 2-ethylidene-cis-3-hexenal is (essentially trans -2-ethylidene-cis-3-hexenal).

^ H

The mass spectral analysis (low resolution) shows the main m / e ratios: 39, 41, 109, 81, 67, 95 124 (parent peak).

The NMR spectrum gives (ppm): (solvent CCl-):

J (cps) number of peak assignment

Protons

9.04 7 3 triplet CH ₃ -CH ₂ -8.12 6 3 doublet CH ₃ -CH = C-CHO.

509808/1085

- 38 -

J (cps) number of peak assignment protons

4.34 4 2 doublet ice C ₂ H ₅ -CH-CH-

C 3.56 6 1 quartet -CH = C-CHO

C 0.72-1 singlet -CIT-C-CHO

The 2-ethylidene-3-hexenal obtained has a value at 1.5 ppm pleasant fresh green aroma with a greasy waxy Character on. At 15 ppm in water, the hexenal derivative has a fresh, green, waxy character. In a 12% sucrose solution containing 0.1% citric acid, at 1.5 ppm it has a fresh green, waxy character reminiscent of fresh citrus fruit peel. At 33 ppm in aqueous solution it has a clean, green, pleasant and intense leaf-like appearance Smell on. The taste is reminiscent of the white fleshy material or albedo, of oranges. Of the The smell and taste of 2-ethylidene-3-hexenal at 33 ppm gives the flavor properties that are found in citrus fruit juices step forward.

Example XIV

Production of 2-ethylidene-6-methyl-cis-3-heptenal

- 39 -

509808/1085

A solution of 5.40 g of isobutylacetylene in 50 ml of diethyl ether is treated with 30 ml of 2.2 η n-butyllithium in hexane at ~ 20 ° C, and after several minutes the resulting solution is treated with 8.50 g of diethoxyacetonitrile and then slowly warmed to room temperature. After about 1 _P 5 hours, the dark mixture is cooled and brought to a pH of about 2 with 10% sulfuric acid.

The layers are then separated and the organic layer becomes successively more aqueous with water and more saturated Washed sodium bicarbonate solution and then dried over sodium sulfate. Evaporation of the solvent results 4.6 g of a dark oil which, according to IR and NMR analyzes 1 "i-diethoxy-e-methyl-S-heptyn ^ -one contains.

A solution of ethylidene triphenylphosphorane is prepared by mixing 17.0 g of ethyltriphenylphosphonium bromide with 20 ml of 2,3 η phenyllithium in a 70; 30 benzene / ether carrier. This is added to the Heptynon, wherein the temperature is kept below 3O ⁰ C under cooling.

A few minutes after the addition is complete, the mixture is divided between the water and ether phases. The 'layers are separated and the organic phase is dried over sodium sulfate and evaporated. Of the The residue is dissolved in hexane and filtered to remove triphenylphosphine oxide. After evaporation of the hexane 10.4 g of the crude acetal obtained are hydrolyzed to the acetylenic aldehyde in 30% strength aqueous acetic acid.

- 40 509808/1085

The crude aldehyde is isolated by partitioning it between water and ether; the ether layer is gradually filled with water and saturated aqueous sodium carbonate, dried over sodium sulfate and the solvent evaporated. The residue is in hexane solution over 1.0 g Lindlar catalyst (5% palladium on potassium carbonate, poisoned with Lead acetate) hydrogenated at a pressure of about 4 atmospheres.

The mixture is filtered and the solvent evaporated to give 3.8 g of a dark oil from the 2-ethylidene-6-methyl-cis-3-heptenal is obtained by preparative GLC. The NMR spectrum of the material shows:

Shift Za hl of protons Peak Assignment 1, OO 6th Doublet -HC (CH ₃ J ₂ 1, 70 2 quartet = C-CH ₂ 1.88 3 Doublet -CO-C = C-CH ₃ 5.80
6.70 2
1 Multiplet
quartet olefinic
Protons
CH ₃ -CH = CC = O 9.37 1 Singlet Formy! Proton The material

- 41 -

509808/1085

has a green, flowery, violet-like, faint cucumber odor.

Example XV Preparation of 1,1-dimethoxy-cis-3-hexen-2-one

6 g of 1,1-dimethoxy-S-hexyn - ^ - one (from Example XII) are stirred under hydrogen gas in an atmosphere in 40 ml of hexane, which contained 0.6 g of Lindlar catalyst (palladium on potassium carbonate, poisoned by lead acetate) and 4.0 g of quinoline. The reaction is over, if only 1% of the starting material (1,1 = dimethoxy-3-hexyn-2-one) remains.

The mixture is filtered and the quinoline washed out with dilute aqueous hydrochloric acid. The organic Layer is washed with saturated aqueous sodium bicarbonate solution and then with sodium chloride and the solvent evaporates. It is determined by GLC and NMR that the raw material essentially 1,1-dimethoxy-cis-3-hexen-2-one represents the following structure:

Example XVI Production of 1,1-dimethoxy-trans-3-hexen-2-one

509808/1085

- 42 -

Öas according to Example XV produced crude product is in 6 ml of acetic acid dissolved with 0.1 g of sodium iodide. GLC on Carbowax (polyethylene glycol) shows that 1,1-dimethoxy-cis-3-hexen-2-one into a new material a later retention period. After half an hour, less than 5% of the "ice" material remains,

The material is made by dividing it into water and ether, washing the ether layer successively "with aqueous sodium bicarbonate and saline and then dried over 4A molecular sieves. Evaporation of the solvent yields 5.0 g of yellow oil. It is shown by NMR and GLC that essentially all of the trans material has the structure:

Example XVII

Ethy1triphenylphosphonium bromide (3.71 g) and 6.3 ml of 1.6N n-butyllithium are mixed in ethereal solution and 1.58g of the 1,1-dimethoxy-trans-3-hexen-2-one of Example XVI are added, the Temperature is kept below 30 ⁰ C. After a few minutes the mixture is filtered and the solvent evaporated. After a small amount of solid is thus obtained, the residue is dissolved in isopentane, filtered and evaporated again to give 1.10 g of a yellow-orange oil.

509808/1085 -43-

The presence of two acetals of 2-ethylidene-2-hexenal, in particular the cis and trans isomers of the ethylidene group, is indicated by GLC and NMR: cis-2-ethylidene-trans-hexenaldimethyl acetal and trans-2-ethylidene-trans-3-hexenaldimethyl acetal. The acetal material is dissolved in 2 ml of water and 3 ml of acetic acid with a small amount of sodium iodide isomerization reagent. After a few minutes, the GLC shows complete hydrolysis (in the absence of sodium iodide, a mixture of cis and trans ethylidene isomers of the aldehydes is obtained). The product is obtained by dividing it into water and ether. The organic layer is washed successively with water, aqueous sodium bicarbonate and aqueous sodium chloride and finally evaporated to give 0.70 g of an orange oil. The main peak (80%) obtained by preparative GLC represents trans-2-ethylidene-trans-3-hexenal of the following structure:

Example XVIII

Production of (Z) -2-ethylidene- (Z) -3-hexenal (or cis-2-ethylidene-cis-3-hexenal)

A 4.20 g xthy1triphenylphosphonium iodide slurry in 30 ml of ether is mixed with 4.3 ml of 2.3 η phenyllithium in benzene: ether to obtain a deep orange solution. 1,1-Dimethoxy-3-hexyn-2-one, which according to Example XII

509808/108 5

- 44 -

(1.56 g) are added, the temperature being kept below 30 ^° C. The resulting mixture is stirred for 1 hour. Water and more ether are added, the mixture is filtered, the layers are separated, and the organic layer is washed with brine and then evaporated. The residue is dissolved in isopentane, filtered and evaporated to give 2.0 g of an orange colored oil. The crude product is hydrogenated at about atmospheric pressure in 10 ml of pyridine over 0.2 g of palladium on barium sulfate and the material is obtained by dividing it into water and ether. The organic layer is washed several times with water and then saturated aqueous sodium chloride.

After removing the solvent, a red-orange oil remains which contains some pyridine. The main product is through preparative GLC isolated. The collected material (140 mg) is hydrolyzed by stirring in ether with 5% sulfuric acid. After 11/2 hours at room temperature, the mixture is through Separation of the layers, washing the ethereal layer with aqueous Sodium bicarbonate and then with saturated aqueous sodium chloride and evaporation through a Vigreaux cologne worked up to obtain 110 mg of a pale greenish oil with a fresh "green" aroma.

It is determined by GLC to contain 10% acetal, while the NMR shows that it contains 20% of the stable isomer. The main product represents the cis »2-ethylidene-cis-3-hexene isomers of the following structure:

509808/1085 - 45 -

Example XIX Orange flavor preparation

An orange flavor preparation is made by mixing the following ingredients:

Components parts

natural orange oil 13.00 acetaldehyde 1.50 Ethyl acetate 0.10 Ethyl butyrate 0.50 Propanal 0.10 trans-2-hexenal 0.10 Ethyl alcohol (95%) 60.00 Fusel oil 0.05 Propylene glycol 24.65

This is referred to as flavor "A". A second preparation Flavor, "B" is obtained by the addition of trans-2-ethylidenecis-3-hexenal (1% in ethanol) produced to an amount of flavor "A".

Each of flavors "A" and "B" is made into 32 ° Baume syrup in an amount of 56.7 g / 3.8 l (2 ounces / gallon) a syrup for combining with water to make a drink. That using the taste Drink made "A" is an acceptable orange drink with good properties, taste and intensity.

- 46 .- 509808/1085

The unta: drink made using flavor "B" has a much improved taste. The improvement attributed to ethylidenhexenal can be traced back on:

1. A greater degree of natural character from fresh squeezed orange juice.

2. An increase in pulp-like notes.

3. Greater orange flavor depth.

Example XX Tobacco flavor

Two tobacco flavor preparations are made by mixing made of the following components:

Approach A Components Parts Pyrolignic acid 10.00 solid corn fiber extract 18.00 solid Foenugreek extract 3.50 Vanillin 0.15 Cyclotene 0.05 2-ethyl-3-methylpyraz in 0.10 Methyl heptynyl carbonate 0.05 Eugenol 0.10

- 47 -

509808/1085

trans-2-ethylidene-trans-3-hexenal (prepared according to
the procedure of the example

XVII) Approach B Components 1.00 Propylene glycol 2-ethyl-3-methylpyrazine 67.05 2-methylvaleric acid Methyl heptynyl carbonate Parts Pyr ο lign insäur e 0.10 trans-2-ethylidene-cis-3-
hexenal (manufactured according to
the procedures of the example
XII) 1, 00 Vanillin 0.25 solid Foenugreek extract 10.00 glycerin 1, 00 water 0.02 solid corn fiber extract 2.50 Propylene glycol • 16.75 20.00 15.00 33.38

Both approaches "A" and "B" are used in tobacco as a flavor enhancing means "They favor the sweet, maple-like, nut-like character and promote the natural taste of tobacco, the tobacco blend, in which the flavors are used, including:

509808/1085

- 48 -

Ingredients quantity

Virginia Tobacco 28%

Burley 48%

Leftover tobacco (oriental,
Turkish tobacco leaves, reconstituted tobacco) 24%

Example XXI Perfume preparation

It becomes a perfume preparation by mixing the following Components produced:

Components parts

Linalool 30

Linalyl acetate 10

Terpineol Coeur 5

Nerol Coeur 10

Terpinylacetate 2

Geranyl acetate 2

Nerylacetate 2 Methyl anthranilate 1

Citral 10

n-decyl alcohol 1

n-dodecyl alcohol 5

n-dodecanal 15

n decanal 30

n-nonanol 3

n-nonanal 5

n ^ decyl acetate 3

509808/1085 " ⁴⁹ "

n-dodecyl acetate

trans-2-ethylidene-ci s-3-hexenal (prepared according to the procedure of Example XII)

The ethylidenhexenal gives this terpeneless orange perfume preparation a natural, bitter orange character,

Example XXII

Strawberry flavor preparation

A strawberry flavor concentrate is made by mixing the following ingredients;

Components percent

Naphthyl ethyl ether 0.96 Ethyl methyl phenyl glycidate 2.88 Vanillin 2.66 2-methyl = 2-pentanoic acid 3.90 Ethyl acetate 9.58 Isoamyl butyrate 12.25 Ethyl butyrate 26.20 Isoamyl butyrate 40.57

1- (propyl'-enyl) -3,4,5-trimethoxybenzene 0.50

trans-2-ethylidene «-cis ~ 3-hexenal (produced according to the procedure of the example

XII) 0.50

- 50 -

509808/1085

The concentrate produced in this way is dissolved in its four times its volume of propylene glycol and the mixture added to a simple syrup in the amount of 227 g / 3.8 l of syrup.

The syrup is acidified by adding 43 g of a 50% strength aqueous citric acid solution to each 3.8 l of syrup. A Carbonated drink is made by mixing 28.3 g of the acidified and flavored Syrups made to 142g of carbonated water. The drink thus produced has excellent freshness Strawberry flavor and it is found to be one in the same way *. trans-2-ethylidene-cis-3-hexenal generated Drink is vastly superior. The one without trans-2-ethylidene-cis-3-hexenal The produced drink lacks fresh green flavors, as found in natural ones Strawberry flavors and aromas. Such fresh green notes are made possible by the trans-2-ethylidene-cis-3-hexenal delivered.

Similar good results can be obtained in changing the organoleptic Properties of consumer materials with other 2-alkylidene-3-alkenals according to the invention, such as, for example the isomers of 2-ethylidene-6-methyl-3-heptenal and the like. The different isomers show something different organoleptic properties as will be understood in view of the present description.

* but without

- 51 -

509808/1085

Claims (1)

Claims 1. Process for the preparation of 2 ~ alkylidene-alkenals " characterized by the process stages of (i) Implementation of an alkenal of the structure Ί ■ with bromine or chlorine , creating a C ^ haloalke nal of the structure is obtained j - 52 - 509808/1085 (ii) Replacement of the haloalkenal with an alkylidene phosphorus compound or an alkyl magnesium halide to produce 1-alkylidene-2-alkene halide j (iii) Conversion of the 1-alkylidene-2-alkene halide with magnesium, alkali metal or an alkyl alkali metal compound, whereby a metallic derivative of an alkylidene of the structure is obtained! and (iv) Fixation of the metallic derivative of the alkylidene with a trialkyl orthoformate or a Di-lower alkylformamide, wherein R _{1 is} lower alkyl and one of R ₃ or R _{4 is} lower alkyl and the other of R ₃ or R- is hydrogen, and M is Mg X, lithium, sodium or potassium, where X is bromine, chlorine or iodine. 2. The method according to claim 1, characterized in that the Alfcenal produced in this way has the formula - 53 509808/1085 having. 3. The method according to claim 2, characterized in that the alkyl group represented by R- is methyl or ethyl and the _{alkyl group represented by R 3} or R "is methyl ,, ethyl or isopropyl, ο The method according to claim 1 , characterized in that step (ii) is the reaction of the haloalkenal with a Grignard reagent of the formula Mg X ' comprises where X "is bromine or chlorine and one of R, or R- is a lower alkyl group and the other Represents hydrogen to give an organometallic compound of the formula; OMgX ' 509808/1085 -54- wherein R. is lower alkyl and X is halogen, Hydrolysis of the organometallic compound with a hydrolyzing agent selected from the group which consists of dilute mineral acids and acid salts, as a result of which a hydroxyalkene is formed of the structure: H ^R 4 R ₃ OH and reacting the hydroxyalkene with a dehydrating agent to give the corresponding alkylidene alkene halide the formula 5. The method according to claim 4, characterized in that that an alkali metal bisulfate is used as the dehydrating agent. 6. The method according to claim 5, characterized in that that the temperature is 200-25O ° C. 7. The method according to claim 4, characterized in that that an oxide is used as a dehydrating agent. 509808/1085 - 55 - 8 "Method according to claim 1, characterized in that it is calibrated η e t that in step (iii) the Älkylidenalkenhalogenid by reaction of the haloalkenais with a phosphorus compound the formula MR,- • / ⁵ R ⁸ - C = P _v R _c R ^{5 R} 5 wherein R ^{5 is} a lower alkyl group and R _{5 is} aryl or lower alkyl. ο The method of claim ₁ 8 characterized in that the reaction is carried out at a temperature from -10 to 100 ⁰ C ₀ 10. The method according to claim 1, characterized in that that the orthoformate is a lower alkyl orthoformate. 1t. The method of claim 1 _r characterized in that the Halogenalkenal tri-substituted phosphorus and it is reacted IVAT in step (ii) with an alkylidene "? that owns the structure wherein R _{5 is} phenyl or lower alkyl to give a mixture of cis and trans haloalkylidene isomers of the structure 5 0 9 8 0 8/1085 - 56 - and wherein in step (iii) the haloalkylidene isomer mixture is reacted with magnesium to form a Grignard reagent that has the structure: R «.H
R. \ JL__MgX ' ^R 4 and wherein in step (iv) the Grignard reagent is reacted with a trialkyl orthoformate to form 2-alkylidene-trans-3-alkenal, wherein R _{1 is} lower alkyl, one of R ₃ or R _{4 is} lower alkyl and the other is hydrogen, X is halogen and X ^{1 is} chlorine or bromine. 12. The method according to claim 4, characterized in that that in step (iii) the alkylidene alkene halide reacted with magnesium to form a Grignard reagent and in stage (iv) the Grignard reagent with a trialkyl orthoformate to form a 2-alkylidene trans-3-alkenal is implemented. - 57 - 509808/1085 13. The method according to claim 1, characterized in that that in step (iii) the 1-alkylidene-2-alkene halide is reacted with an alkyl alkali metal to form an alkali metal alkylidene and in step (iv) the alkali metal alkylidene with a di-lower alkylformamide to form a 2-alkylidene-3-alkenal of the structure is implemented. 14. The method according to claim 13, characterized in that that n-butyllithium is used as the alkyl alkali metal. 15., The method according to claim 1, characterized in, that in step (iii) the 1-alkylidene-2-alkene halide with magnesium to form a Grignard reagent is reacted and in step (iv) the Grignard reagent with a trialkyl orthoformxate to produce a 2-alkylidene-trans-3-alkenal is implemented. 6. The method according to claim 15, characterized in that that as trialkyl orthoformate triethyl orthoformate used. - 58 - 509808/1085 17. Essentially pure 2-alkylidene-3-alkenals
formula wherein one of R ₁ and R- is hydrogen and the other
Is methyl and one of R ₃ and R ₄ . Hydrogen and that
other represents an alkyl group containing 2 to 4 carbon atoms. 18. 2-Alkyliden-3-alkenal according to claim 17, wherein R-. or
R. represents ethyl or isobutyl. 19. 2-alkyliden-3-alkenal according to claim 17, wherein R. methyl represents. 20. 2-Alkyliden-3-alkenal according to claim 17, wherein R .. is methyl and R _{3 is} ethyl. 21. 2-Alkyliden-3-alkenal according to claim 17, wherein R _{1 is} methyl and R _{3 is} isobutyl. 50980 8/1085