Enantioselective alkynylation of aldehydes catalyzed by [2.2]paracyclophane-based ligands.

Org Lett

cynora GmbH, Kaiserstr. 100, D-52134 Herzogenrath, Germany.

Published: June 2004

[reaction: see text] [2.2]Paracyclophane-based ketimine ligands were evaluated as catalysts for the enantioselective addition of in situ-prepared alkynylzinc reagents to aldehydes. The initial high activity and enantioselectivity of these ligands could be improved by an additive screening. The final protocol gives chiral propargyl alcohols in up to >98% ee.

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http://dx.doi.org/10.1021/ol049596bDOI Listing

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