Highly efficient, catalytic Meerwein-Ponndorf-Verley reduction with a novel bidentate aluminum catalyst

Double electrophilic activation of carbonyl groups allows a modern variant of the Meerwein-Ponndorf-Verley reduction to be carried out under mild conditions with bidentate catalyst 1 (see reaction). Various carbonyl substrates can be reduced efficiently at room temperature in CH₂Cl₂ with 2-propanol or sec-phenthyl alcohol in the presence of a catalytic amount of 1. This system is also applicable to the Oppenauer oxidation of secondary alcohols to the corresponding ketones.