DE2233245C3 - 1,3-Dioxolanes and processes for their preparation and flavor compositions containing these compounds - Google Patents

Description

with n-butyric acid or a functional derivative Experiment 2
the same esterified, whereby in the formulas the

R ² and R ³ radicals have the meaning given in claim 1 to the butter flavor meaning mentioned in experiment 1, composition A 10 parts of the

3. Flavor composition, gekenn- 45 game 2 produced 2-methyl-2- (I'-hydroxyethyl) -drawn added by a content of a compound 4-n-butyroxymethyl-dioxolane. The so conservative Claim 1. tenc composition C is used for flavoring

of pastries used in a dosage of 0.5% o.

The product flavored with the composition C

50 bück is the one with 0.5 ° / _{00 of} the composition A

Aromalized taste clearly superior.
The invention relates to 1,3-dioxolanes in general

Formula experiment 3

R ² R ³

\ / 55 From a mixture D, consisting of 1000 genes

C (I) important parts of the aroma composition A of the

/ \ suchs 1 and lOOGc weight parts of example 3

0 O produced 2 - (T -Methyl-propyl) -4-η-butyroxy-

1 I methyl-dioxolane as a mixture E, consisting of CH ₃ -CH ₂ -CH ₂ -COO-CH ₂ -CH-CH ₂ 60 from 1000 parts by weight of the aroma composition

tongue A and 100 parts by weight of that of Example 32

in which R ^{2 is} a hydrogen atom or a methyl radical of the DT-OS 14 93 572 known 2- (l'-isopiopyl) -

and R ³ the l'-propenyl radical, l'-hydroxyethyl radical or 4-n-butyroxymelhyl-dioxolane, each became one

Represents 2'-methylpropyl radical, and processes for their 1% solution in propylene glycol and these

Manufacture as well as such compounds containing 65 in turn as a 0.05% igc solution in sugar syrup

Flavor compositions. an expert group of 5 people on their Gc-

The compounds I according to the invention are taste-tested. It was found that the

Surprisingly, the special flavor mixture D creates an intensely creamy aroma of fresher

Has butter, while mixture E completely lacks the fresh butter note.

The!, 3-Dioxolanes of the above formula I are prepared by being known per se Way either

a) the glycerol-n-mono-n-butyric acid ester of formula

IO

CH ₃ -CH ₂ -CH ₂ -COO-CH ₂ -CHOH-CH ₂ -Oh

with a carbonyl compound of the general formula R ² —CO —R ³ (II)

cyclized or that one

b) a 4-hydruxymethyl-dioxolap of the general formula

R ²

R ³

(III)

HO-CH ₂ -CH-CH ₂

esterified with n-butyric acid or a functional derivative thereof, the radicals R ² and R ³ in the formulas being as defined above.

In method a), an aldehyde or ketone of the general formula 11 is used with the ester in question acetalized or ketaiized as usual. The acetalization or ketalization takes place advantageously by heating the mixture of reactants in the presence of a solvent and expediently using an acidic catalyst as well as progressive removal of the one that forms Water, e.g. B. by means of a Schleppmittcls.

The solvents customary for this purpose, such as aromatic and saturated aliphatic ones, can be used as entrainers Hydrocarbons, e.g. B. benzene, toluene or n-pentane can be used.

Suitable acidic catalysts are those for acetalization or ketalizations customary compounds, e.g. B. mineral acids such as sulfuric acid, phosphoric acid, Perchloric acid; strong organic acids such as 1 richloroacetic acid or p-toluenesulfonic acid or boron fluoride.

The esterification method b) is carried out according to methods known per se, e.g. B. by acylation according to Schotten - Ba um an η in the presence of a base, or by reaction of the alcohol III with the n-butyric acid or its anhydride in the presence of an acidic catalyst, expediently using a solvent and with the progressive removal of any forming Water. The compounds mentioned above for method a) come as acidic catalysts in question.

For 2,4-di- or 2,2,4-trisubstituted dioxolanes, as represented by the compounds I, the theory looks ahead an cis and a trans form are available (compare, for example, J. Chem. Soc. 1970, 263). The formula I is said to be the ice and trans forms as well as mixtures of these two forms. According to the invention according to the process variants Compounds I prepared a) and b) mostly fall as cis-trans isomer mixtures with approximately the same Amounts of ice and trans form.

example 1

300 g of glycerol-a-mono-n-butyric acid ester and 150 g of crotonaldehyde are dissolved in 1200 ml of benzene and boiled on a water separator in the presence of 4 g of p-toluenesulfonic acid. After the reaction mixture has cooled, it is transferred to a separating funnel and washed successively with water, 5% sodium bicarbonate solution and water until neutral. The solvent is then distilled off and the residue is fractionally distilled on a packed column. The case with a yield of 75% obtained 2- [l'-propenyl] -4-n-butyroxymethyi-dioxolane boils under a pressure of 0.4 mm at 101-102 ⁰ C; n? = 1.4520.

Example 2

In a 4-neck stirred flask with attached water separator 200 g of acetylmethylcarbinol, 366 g of glycerine-rt-mono-n-butyric acid ester, 1300 ml Benzene and 8 g of p-toluenesulfonic acid mixed and refluxed with stirring. After 5 hours the amount of water excreted is about 40 ml, corresponding to an almost complete conversion. The reaction mixture is cooled and poured into 500 ml of saturated aqueous sodium bicarbonate solution. The benzene solution is separated off in a separating funnel and washed thoroughly with water. After a short drying period, the benzene is distilled off and the residue is fractionated on a packed column.

Are obtained 182g of 2-methyl-2-D'-hydroxyethyl] -4-n-butyroxymethyl-dioxolane, bp 0.2 / 104 to 106 ⁰ C. n'f = 1.4487 in the form of a mixture of 2 stereoisomers in a ratio of about 1: 1.

Example 3

According to the method described in Examples 1 and 2, using the appropriate starting materials, 2 - (2 '- methylpropyl) -4-n-butyroxymethyi-dioxolane with a boiling point of 0.3 / 85 ° C., H ¹ S = 1.4378.

Example 4

23 g of 2- [l'-propenyl] -4-hydroxymethyl-dioxolane are added together with 12.5 g of absolute pyridine and 250 ml of chloroform in a reaction vessel, and the mixture is cooled to - 10 ⁰ C cooled. 18 tons of n-butyric acid chloride are then added dropwise over the course of 20 minutes and the mixture is stirred for a further 5 hours, the temperature being allowed to rise gradually to room temperature. The reaction mixture is then washed with sodium bicarbonate and water, dried and freed from the solvent. By distilling the residue, 28 g of 2- [Γ-propenyl] -4-n-butyroxymethyl-dioxolane with a boiling point of 0.05 / 90 to 92 ° C; n ?, "= 1.4535.

Claims (2)

1 2 borrowed properties, especially due to their butter aroma Patent claims: from. They are therefore used as flavors in aromas 1. 1,3-Dioxolanes of the general formula suitable for compositions. 5 The concentration of the compounds I in flavors-R ² R ³ compositions, such as butter flavors, can be between \ / see about 0.01 and 100 per mil are preferred C (1) it is in the range from 0.1 to 10 parts per thousand; in the / \ aromatizing with such aromatic compositions 0 O io ten finished products (such as pastries, fruit tarts, etc.) 1 I it can be correspondingly lower, for example in the CH ₃ —CH ₂ —CH ₂ —COO — CH ₂ —Ch — CH ₂ range from 0.1 to 10 ppm. In the experiments below, the in which R ^{2 is} a hydrogen atom or a methyl taste properties of some residues according to the invention and R ^{3 is} the l'-propenyl residue, l'-hydroxyethyl compounds,
represents radical or 2'-methylpropyl radical. ,. 2. Process for the preparation of the compounds Experiment 1 according to claim 1, characterized in that a flavor composition A, consists one in a known manner either from: a) the glycerol-u-mono-n-butyric acid ester of 20 parts by weight Formula diacetyl 520 Butyric acid 370 CH ₃ -CH ₂ -CH ₂ -COO-CH ₂ -CHOH-CH ₂ Oh lactic acid 50 Vanillin 40 with a carbonyl compound of the general 25 butyric acid ethyl ester 10 Formula Heliolropin 5 R ² - CO - R ³ (II) benzaldehyde 5 1000
cyclized or that one b) a 4-hydroxymethyl-dioxolane of the general 30 is I part by weight of that prepared according to Example 1 NEN formula 2- (l'-propenyl) -4-n-butyroxymethyl-dioxolane to- _{2 3} joined. Composition B thus obtained is that "* ■. Ζ Composition A (with the well-known butter \ aroma Diacetyl) clearly superior in taste. 35 Is namely with the compositions A and B / \ Pastries, whereby the dosage of the aromas 9 9 compositions at 50 g per 100 kg dough (0.5 ^o / _oo ) cherishes, I I so indicates that flavored with composition B. HO CH ₂ CH CH ₂ pastries have a clearly finer butter taste.