Highly Enantioselective Phenylacetylene Additions to Both Aliphatic and Aromatic Aldehydes

摘要

The readily available and inexpensive BINOL in combination with Ti(O~iPr)_4 is found to catalyze the reaction of an alkynylzinc reagent with various types of aldehydes including aliphatic aldehydes, aromatic aldehydes, and other α,β-unsaturated aldehydes to generate chiral propargyl alcohols with 91-99% ee at room temperature. No previous chiral catalysts have exhibited such a broad scope of enantioselectivity with respect to the type of aldehydes for this reaction.