Reformatsky Type Reaction with New Aluminium Reagents Containing Al–Sn or Al–Pb Linkage

Treatment of α-bromo carbonyl compounds with the reagent prepared from n-Bu3SnLi and Et2AlCl or from SnCl2 and Et2AlCl affords enolates which react with ketone or aldehyde to give β-hydroxy carbonyl compounds in good to excellent yields. The reactions proceed similarly with the reagents which are generated from R3PbLi (R=Ph, n-Bu) and Et2AlCl. Catalysis by the added Pd(PPh3)4 complex promotes the reduction effectively and improves the yields of the desired adducts. The regio- and stereoselectivities are disclosed.