Patent ID: 8110700

Claim:
A process for preparing vinyl carboxylate compounds of the formula I: in which a) R 1 is H or —COO—CH═CH—R 2 and n is 1, b) R 1 is C 1 -C 20 -alkyl, C 2 -C 20 -alkenyl or C 3 -C 7 -cycloalkyl, and n is 1, 2 or 3, where R 1 is optionally substituted by 1, 2 or 3 radicals which are each independently selected from phenyl, halogen, hydroxyl, C 1 -C 4 -alkoxy, amino, mono-C 1 -C 4 -alkylamino, di-C 1 -C 4 -alkylamino, —OCOR 3 , —COOR 3 , —CONR 4 R 5 , —NR 4 COR 5 , —OCONR 4 R 5 or —NR 4 COOR 5 , or c) R 1 is aryl and n is 1, 2, 3, 4, 5 or 6, where aryl may optionally be substituted by 1, 2 or 3 radicals which are each independently selected from C 1 -C 4 -alkyl, halogen, hydroxyl, C 1 -C 4 -alkoxy, amino, mono-C 1 -C 4 -alkylamino, di-C 1 -C 4 -alkylamino, —OCOR 3 , —COOR 3 , —CONR 4 R 5 , —NR 4 COR 5 , —OCONR 4 R 5 or —NR 4 COOR 5 ; R 2 is H, C 1 -C 8 -alkyl, phenyl-C 1 -C 4 -alkyl, phenyl which is optionally substituted by 1 or 2 C 1 -C 4 -alkyl groups, or C 3 -C 7 -cycloalkyl; R 3 is C 1 -C 4 -alkyl; R 4 and R 5 , which may be the same or different, are each H or C 1 -C 4 -alkyl; comprising the reaction of a compound of the formula II in which R 1 is H or —COOH and n is 1 or R 1 has the definitions specified above under b) and n is 1, 2 or 3 or R 1 has the definitions specified above under c) and n is 1, 2, 3, 4, 5 or 6, with a compound of the formula III H—C≡C—R 2 (III) in which R 2 has the definitions specified above, in the presence of a catalyst which is selected from one or more salts of perrhenic acid at a temperature of ≦250° C.