Branch selective allylation of acetylacetone catalyzed by Water-soluble rhodium complex catalyst

[RhCl(1,5-cod)]2/PTA is highly active branch-selective catalyst for C-allylation of acetylacetone by allylic carbonates in water/ethyl acetate biphasic system, where either crotyl or 1-methylallyl carbonates gives sterically congested branched allylation product, suggesting formation of a common allylrhodium intermediate.