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

► [RhCl(cod)]2 with 1,3,5-triaza-7-phosphaadamantane acts as active branch-selective catalyst for C-allylation of acetylacetone by allylic carbonates in water/ethyl acetate biphasic system. Either crotyl or 1-methylallyl carbonates gives branch allylation product. An SN2 reaction of acetylacetone to a common 3-methylallylrohodium intermediate is considered to be responsible for this selectivity.