Patent ID: 7622591

Claim:
A process for the manufacture of compounds represented by the following formula III wherein R3 is C2-5-alkanoyloxy, by the reaction of a) a compound represented by the following formula I wherein R′ and R2 are independently from each other H or C1-5-alkyl, with the proviso that at least one of R1 and R2 is not H, and wherein R3 is as defined above, with b) a compound represented by the following formula II wherein R4 is H or CH2—R5, wherein R5 is formyloxy, C2-5-alkanoyloxy, benzoyloxy, C1-5-alkoxy or OSiR6R7R8, wherein R6, R7 and R8 are independently from each other C1-6-alkyl or phenyl, in the presence of a cross-metathesis catalyst, wherein the cross-metathesis catalyst is wherein Cy is cyclohexyl.