5025-86-5Relevant articles and documents
Preparation of 3-pentenoates from 2-pentenoates
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, (2008/06/13)
3-pentenoates are prepared from 2-pentenoates by a process in which(a) a 2-pentenoate of the formula STR1 where R 1 is alkyl of 1 to 12 carbon atoms, cycloalkyl of 5 to 8 carbon atoms, aralkyl of 7 to 10 carbon atoms or aryl of 6 to 10 carbon atoms, is reacted with a compound of the formula IIR 2 -X-H IIwhere R 2 has the meanings given for R 1 and X is an oxygen or sulfur atom, or with a compound of the formula III STR2 where R 3 is hydrogen or R 3 and R 4 are each alkyl of 1 to 12 carbon atoms, cycloakkyl of 5 to 8 carbon atoms, aralkyl of 7 to 10 carbon atoms or aryl of 6 to 10 carbon atoms, and R 3 and R 4 together with the nitrogen atom on which they are substituents may form a 5-membered to 7-membered ring which may additionally contain a nitrogen or oxygen atom as a hetero atom, at from 20° to 300° C., in the presence or absence of a basic catalyst, to give a compound of the formula IV STR3 where Y is --XR 2 or STR4 in which X, R 1, R 2, R 3 and R 4 have the above meanings, and(b) the compound of the formula IV is cleaved in the liquid or gas phase in the presence of an acidic catalyst at from 150° to 450° C. to give a mixture of 3- and 2-pentenoates, and the 3-pentenoate is isolated.
