| abstract |
A method for producing compounds of formula (I), wherein R<1> = H, C1-C6-Alkyl, C1-C6-alkenyl, C3-C6-cycloalkyl or phenyl and R<2> = H or C1-C3-alkyl, characterized in that propyne is reacted with a compound of formula (II), wherein R<1> and R<2> have the above-mentioned meanings, in the presence of a transition metal catalyst system containing ruthenium. |