Platinum complex catalyzed reaction of tributyltin cyanide with alkynes

In the presence of a catalytic amount (5 mol%) of a platinum complex, tributyltin cyanide (1) reacts with dimethyl- (2a) or diethyl acetylenedicarboxylate (2b) to afford cyanostannylation adducts (3a, b) in excellent yields. The reaction proceeds highly selectively affording only a (Z)-isomer. The compounds 3a, b are novel products which possess synthetically useful cyano, alkenylstannyl and alkoxycarbonyl functionalities in the same molecule. Two alkoxycarbonyl functionalities may be indispensable on each alkyne carbon to accomplish the cyanostannylation reaction. Reaction with terminal alkynes gave the stannylated product (6).