CH565516A5 - Delta-3-thiazolines - prepd by reaction of an aldehyde ammonia and alpha-mercaptoacetaldehyde as aromas for foodstuffs - Google Patents

Abstract

Cpds. of formula (I):- (where R 5-7C alkyl, benzyl or 2-methylthioethyl), are prepd. by reacting a cpd. (II): RCOH with NH3 or NH4 salt and with alpha-mercaptoacetaldehyde (III). Reaction is opt. in solvent, pref. diethylether in a ratio (II):(III) of 1:1, using excess NH3 at 0-40 degrees C. (I) have aroma props. esp. of various vegetables. They may be used to aromatise foodstuffs e.g. soups, vegetables, sauces etc.

Description

  

  
 



   The invention relates to flavor compositions. These are compositions with a content of new A3-thiazolines of the formula
EMI1.1
 wherein R is a C7-alkyl radical with the exception of the isopropyl, 2-sec.-butyl and isobutyl radical.



   The C3-7 alkyl radical can be straight-chain or branched. It includes, for example, the following groups: propyl, butyl, pentyl, hexyl.



   The compounds of the formula I have special aroma properties, in particular they have interesting vegetable notes, such as bean, tomato, pepper, asparagus or potato notes.



   The compounds of formula I can accordingly be used for flavoring foods, e.g. B. soups, vegetables, sauces, etc. The distinctive taste qualities of the new compounds allow their use in the finished product in low concentrations, e. B. in the range of 0.01-10 ppm, preferably 0.1-1 ppm.



   The compounds of the formula I can, if appropriate with other flavoring constituents, be mixed with the customary carriers and / or thinning agents and, if appropriate, with emulsifiers to give flavoring agents which give food a vegetable taste or enhance such a taste. However, the compounds of the formula I can also be added alone to the products to be flavored. In this case special attention must be paid to an even distribution in the product to be flavored when adding.



  If the compounds serve as components for the production of artificial flavors, these flavors can e.g. B.



  can be formulated into liquids, pastes or powders. The products can e.g. B. spray-dried, vacuum-dried or lyophilized. The formulation of such artificial flavors and the flavoring of foods can otherwise be done in a manner known per se [cf. J. Merory; Food flavors, composition, manufacture and use; Avi Publ. Co. Inc. Westport (1968)].



   Example Aroma composition (type pear) AB Eugenol (10% in alcohol) 10.0 10.0 Geraniol (10% in alcohol) 10.0 10.0 Acetic acid-lin alyl ester 10.0 10.0 Vanillin (10% in alcohol) 20.0 20.0 anethole (1% in alcohol) 20.0 20.0 acetic acid piperonyl ester (10% in alcohol) 25.0 25.0 propionite geranyl ester (10% in alcohol) 50.0 50.0 maltol (2% in alcohol) 50.0 50.0 amyl acetate 100.0 100.0 alcohol 705.0 655.0 n-hexyl- # -thiazoline (1% in alcohol) - 50.0
1000.0 1000.0
The presence of n-hexyl-A3-thiazoline in the above composition B gives the aroma a much fuller, greenish-fruity, rounded pear note.



   The new compounds can be obtained by using an aldehyde of the formula
EMI1.2
 with ammonia or an ammonium salt and α-mercaptoacetaldehyde.



   Examples of ammonium salts are ammonium salts of mineral acids, e.g. B. of hydrohalic acids, such as chlorine, bromine or hydrogen iodide, of sulfuric acid, nitric acid, etc. The a-mercaptoacetaldehyde can also in situ from suitable Voläuferm, such as. B. from the dimer (bis-mercaptoacetaldehyde) or from other α-substituted acetaldehydes, such as. B. from a-haloacetaldehyde, by reaction with, for example, sodium hydrogen sulfide.



   The reaction of the starting materials can be carried out with or without a solvent. Examples of such solvents are: alcohols, e.g. B. alkanols such as methanol, ethanol, etc.; Ethers such as diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, etc .; aliphatic or aromatic hydrocarbons, e.g. E.g., pentane, hexane, benzene, toluene, etc .; secondary and tertiary amines such as diethyl and triethylamine, etc .; Amides such as dimethylformamide, etc .; Water, or also active ammonia. Diethyl ether is a preferred solvent.



   The molar quantitative ratio of the compound II to the α-mercaptoacetaldehyde is expediently 1: 1, but each of the two components can also be used in excess, e.g. B. in the ratio 2: 1, can be used.



   The ammonia can be used in any amount, but an excess of only the aldehyde of the formula II and the α-mercaptoacetaldehyde is recommended.



  According to a preferred embodiment of the process, gaseous ammonia is passed through the reaction mixture containing the compound II, α-mercaptoacetaldehyde and solvent.



   The reaction can be carried out in the presence or absence of a dehydrating agent.



  If the reaction is carried out in an organic solvent, it is expedient to use anhydrous sodium sulfate as the dehydrating agent.



   The reaction temperatures are conveniently between about -30 and 100 ° C. A preferred temperature range is from about 0 to 40 ° C., with the heating preferably being a little more intense towards the end of the reaction, e.g. B. to 60 C. The reaction time is, depending on the reaction temperature, between 5 minutes and 24 hours, at room temperature preferably about 10 to 30 minutes.



   The reaction product can be isolated by methods known per se, e.g. B. by filtering off any sodium sulfate present and fractional distillation of the filtrate.



   Synthesis example 1
In a mixture of 43.8 g of dimeric α-mercaptoacetaldehyde [M. Thiel, F. Asinger, K. Schmiedel, Ann., 611, 126 (1958)], 95.2 g of caproaldehyde, 30 g of anhydrous sodium sulfate and 200 mylather were slowly passed in ammonia gas with stirring for 20 minutes.



  The mixture was then heated to 60 and ammonia gas was passed in for a further 10 minutes. The sodium sulfate was filtered off, washed twice with 20 ml of ether each time and the solvent was distilled off at normal pressure through a column. Fractional distillation of the residue over a Vigreux column gave 61.3 g.



   (Yield 68%, based on α-mercaptoacetaldehyde) 2-n-pentyl- # -thiazoline, boiling point 5 96-97, nD20 = 1.4945. IR (fl.): Bands et al. at 1645, 1470 and 1220 cm-Ú.



   Odor: green, leguminous;
Taste: bean-like, pea-like, sulphurous.



   Synthesis example 2
By reacting 43.8 g of dimeric α-mercaptoacetaldehyde with 106.1 g of heptanal according to Example 1, 54.28 g (yield 55%, based on α-mercaptoacetaldehyde) of 2-n-hexyl- # -thiazoline, boiling point 0 , 07 84 C, nD20 = 1.4928. IR (fl.): Bands u. a. at 1650, 1470 and 1225 cm-Ú.



   Odor: green, leguminous, remotely similar to pepperni;
Taste: groin, fatty, aldehyde-like, similar to green beans.



   Synthesis example 3
By reacting 52 g of dimeric a-mercaptoacetaldehyde with 79.2 g of n-butyraldehyde according to Example 1, 70.1 g (yield 80%, based on a-mercaptoacetaldehyde) of 2-n-propyl-d3-thiazoline, boiling point 6 70 C, nd20 = 1.5031. IR (fl.): Bands u. a. at 1645, 1465 and 1230 cm-1.

 

   Smell: intense grin, gemtis-like (beans, peas), remotely reminiscent of Hexenal;
Taste: thoroughly, peanut-like.



   Synthesis example 4
By reacting 52 g of dimeric α-mercaptoacetaldehyde with 97 g of n-valeraldehyde according to Example 1, 80.9 g (yield 83%, based on α-mercaptoacetaldehyde) of 2-n-butyl-thiazoline, 84-85 ° C., nD20 = 1.4968 obtained.



     tR (fl.): bands u. a. at 1645, 1465 and 1220 cm¯l.



   Smell: grin, somewhat earthy, carrot-like, slightly pod-like and fruity;
Taste: grisly, earthy, potato-like.

 

Claims (1)

PATENT CLAIM Flavor composition, characterized in that it contains a compound of the formula EMI2.1 where R is a C3-7-alkyl radical with the exception of the isopropyl, sec-butyl and isobutyl radical. SUBCLAIMS 1. Flavor composition according to claim, characterized by a content of 2-propyl-A3 -thiazoline. 2. Flavor composition according to claim, characterized by a content of 2-butyl- # -thiazoline. 3. Flavor composition according to claim, characterized by a content of 2-pentyl- # -thiazoline. 4. Flavor composition according to claim, characterized by a content of 2-hexyl-d 3-thiazoline.