Abstract
Titanium tetrachloride in ethyl acetate can be reduced by Al powder to the corresponding low valent titanium complexes, which can mediate the conversion of some aromatic aldehydes into the corresponding pinacols in 23–93 % yields within 25–120 min under stirring at r.t. When N,N,N’,N‘-tetramethylethylene diamine (TMEDA) is added, the diastereoselectivities of the reactions are improved.
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