Chiral secondary alcohol-induced asymmetric autocatalysis: correlation between the absolute configuration of the chiral initiators and the product

In the presence of various chiral secondary alcohols as chiral initiators, an enantioselective alkylation of a pyrimidine-5-carbaldehyde using diisopropylzinc was examined: a pyrimidyl alkanol was obtained in high yield and enantiomeric excess. The correlation between the absolute configuration of the chiral secondary alcohols and the pyrimidyl alkanol is discussed.

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3,3-Dimethyl-1-phenylbutan-1-olC12H18OEe = 95.5% (HPLC, Chiralpak OD–H)[α]D28=+61.9 (c 0.10, CHCl3)Source of chirality: resolutionAbsolute configuration: modified Mosher method

4,4-Dimethyl-1-phenylpentan-2-olC13H20OEe = 96.6% (HPLC, Chiralpak OD–H)[α]D23=+5.9 (c 0.47, CHCl3)Source of chirality: resolutionAbsolute configuration: modified Mosher method