The palladium-catalyzed vicinal carbonylation of the 1-substituted-3-methoxycarbonyl-2-propynyl methyl carbonates 6 proceeds at room temperature under atmospheric pressure of CO to give the triesters 7 in good yields.
Platinum(II) Chloride Catalyzed Cycloisomerizations of 1,5-Enynes
1,5-Enynes are highly reactive under PtCl2 catalysis and give a range of [3.1.0] bicyclic skeletons. The scope and limitations of this process are presented. Regioisomeric keto derivatives are obtained depending upon the nature of the oxygenated substituent at the propargylic position of the starting substrate.