Allylic alcohols allylate various carbonyl compounds with regio-, chemo- and diastereo-selectivity in the presence of a catalytic amount of PdC12(PhCN)* and two equimolar amounts of tin(I1) chloride.' Here we report that 2-methylenepropane- 1,3-diol, bearing two identical allylic alcohol moieties, has been applied to (i) selective monoallylation, occasionally followed by cyclization to 2-substituted 4-methylenetetrahydrofurans, in ... +"I> 0 OH OH la DMF, room temp. L,, ...