Patent GB-893321-A (GB)
Title: New lactones and their use as flavouring agents
Inventor: BOLDINGH JAN
IPC: C07C57/13
Filed: 1957-08-19
Abstract: The invention comprises lactones of the general formula <FORM:0893321/IV (b)/1> in which R1 and R2 -re hydrogen or C1-5 alkyl groups, at least one being such an alkyl group, and R4 is a bivalent hydrocarbon radical which is mono- or di-substituted methylene group containing 2-9 carbon atoms, not more than 7 being consecutive atoms in an acyclic chain, the group being attached to the lactone ring by a double bond.  Specified R4 groups include alkylidene, aralkylidene and cycloalkylidene groups.  The lactones may be prepared by dehydration of lactonols of the general formula <FORM:0893321/IV (b)/2> wherein R1 and R2 are as above defined and R3 is a monovalent hydrocarbon radical differing from R4 only in having an additional hydrogen atom on the first carbon atom, or by dehydration of the corresponding keto acids HO.CO.CR1 : CR2COR3.  The dehydration is preferably effected by heating with a mixture of acetic acid, acetic anhydride and sulphuric acid.  According to Example 4, the lactone wherein R1 and R2 are methyl and R3 is the group Ph.CH : CH.CH=, may also be prepared by heating a mixture of 2 : 3-dimethyl-maleic anhydride and the sodium salt of gamma-phenyl-vinyl acetic acid at 150 DEG C. while adding acetic anhydride thereto dropwise.  Other examples describe the preparations, by dehydration of the corresponding lactonols, of those lactones wherein (i) R1 and R2 are methyl and R4 is ethylidene or a homologue thereof up to heptylidene, 2-dimethylethyl-methylene, di-ethylmethylene, cyclohexylidene, cyclohexyl-methylene, phenyl methylene or benzyl methylene; (2) R1 and R2 are ethyl and R4 is butylidene, pentylidene or hexylidene; (3) R1 is hydrogen and R2 is methyl and vice-versa and R4 is n pentylidene; (4) R1 and R2 are n-butyl and R4 is n-pentylidene. The preparation of the lactonols is described in Specification 893,322. The lactones are flavouring agents for food (see Groups I and VI).ALSO:Fatty foodstuffs such as butter, margarine and bakery fats are flavoured with lactones of the general formula <FORM:0893321/I/1> wherein R1 and R2 are hydrogen or C1-5 alkyl groups at least one being such an alkyl group and R4 is a divalent non-aromatic hydrocarbon radical which is a mono- or di-substituted methylene group containing 2-9 carbon atoms, not more than 7 being consecutive atoms in an acyclic chain. Specified lactones are those wherein (1) R1 and R2 are methyl and R4 is ethylidene or a homologue thereof up to heptylidene, 2-dimethylethyl methylene, di-ethyl methylene, cyclohexylidene or cyclohexyl-methylene; (2) R1 and R2 are ethyl and R4 is butylidene, pentylidene or hexylidene; (3) R1 and R2 are n-butyl and R4 is pentylidene; and a mixture of lactones wherein R1 is H and R2 is methyl and vice-versa and R4 is pentylidene.  The lactones which may be employed in solution in edible oils, may be used in conjunction with lactones of gamma-hydroxy and delta-hydroxy unbranched paraffinic mono-carboxylic acids containing 8-14 carbon atoms, butyric acid and di-acetyl.  The preparation of the unsaturated lactones is described (see Group IV(b)). Specification 893,322 is referred to.ALSO:Natural and artificial creams, ice-cream, chocolate, bread and dough are flavoured with lactones of the general formula <FORM:0893321/VI/1> wherein R1 and R2 are hydrogen or C1-5 alkyl groups at least one being such an alkyl group and R4 is a divalent non-aromatic hydrocarbon radical which is a mono- or di-substituted methylene group containing 2-9 carbon atoms, not more than 7 being consecutive atoms in an acyclic chain. Specified lactones are those wherein (1) R1 and R2 are methyl and R4 is ethylidene or a homologue thereof up to n-heptylidene, 2-dimethyl-ethyl methylene, diethyl methylene, cyclohexylidene and cyclohexyl methylene, (2) R1 and R2 are ethyl and R4 is butylidene pentylidene or hexylidene, (3) R1 and R2 are n-butyl and R4 is pentylidene, and a mixture of lactones wherein R1 is H and R2 is methyl and vice versa and R4 is pentylidene. The preparation of the lactones is described (see Group IV (b)). It is stated that certain of the lactones have a celery-like flavour or impart a butter-like flavour in appropriate concentrations.  Specification 893,322 is referred to.