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When benzaldehyde and dimethylaluminum 2,6-di-tert-butyl-4-methylphenoxide (abbreviated as DAD) were allowed to react in a 1:1 molar ratio at room temperature for 2h in CH₂Cl₂ solvent, acetophenone (40%), benzyl alcohol (44%), 1-phenylethanol (1%), and 3-hydroxy-1,3-diphenylpropan-1-one (4) (9%) were produced. The reaction using dimethylaluminum 4-bromo-2,6-di-tert-butylphenoxide (abbreviated as DABR) also gave similar products.　In contrast, dimethylaluminum 2,6-diphenylphenoxide (1) led to the methylated product, 1-phenylethanol, as a major product, and both dimethylaluminum 2,6-diisopropylphenoxide (2) and dimethylaluminum 2,6-dimethylphenoxide (3) were quite unreactive.　The reaction of various aliphatic and aromatic aldehydes with DAD (or DABR) gave approximately equimolar amounts of the corresponding methyl ketones and alcohols in good yield.　A mechanism for this transformation can be proposed as follows.　The first step is Lewis acid-base complex formation between an aldehyde and DAD (or DABR).　The corresponding aluminum alkoxide intermediates are then formed by an intramolecular rearrangement of the Lewis acid-base complexes, presumably via a cyclic four-center transition state, and subsequent Oppenauer oxidation gives the corresponding methyl ketones and alcohols.