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Development of Zn-ProPhenol-catalyzed asymmetric alkyne addition: synthesis of chiral propargylic alcohols.

ABSTRACT: The development of a general and practical zinc-catalyzed enantioselective alkyne addition methodology is reported. The commercially available ProPhenol ligand (1) has facilitated the addition of a wide range of zinc alkynylides to aryl, aliphatic, and ?,?-unsaturated aldehydes in high yield and enantioselectivity. New insights into the mechanism of this reaction have resulted in a significant reduction in reagent stoichiometry, enabling the use of precious alkynes and avoiding the use of excess dimethylzinc. The enantioenriched propargylic alcohols from this reaction serve as versatile synthetic intermediates and have enabled efficient syntheses of several complex natural products.

SUBMITTER: Trost BM

PROVIDER: S-EPMC3864595 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Development of Zn-ProPhenol-catalyzed asymmetric alkyne addition: synthesis of chiral propargylic alcohols.

Trost Barry M BM Bartlett Mark J MJ Weiss Andrew H AH von Wangelin Axel Jacobi AJ Chan Vincent S VS

Chemistry (Weinheim an der Bergstrasse, Germany) 20121023 51

The development of a general and practical zinc-catalyzed enantioselective alkyne addition methodology is reported. The commercially available ProPhenol ligand (1) has facilitated the addition of a wide range of zinc alkynylides to aryl, aliphatic, and α,β-unsaturated aldehydes in high yield and enantioselectivity. New insights into the mechanism of this reaction have resulted in a significant reduction in reagent stoichiometry, enabling the use of precious alkynes and avoiding the use of excess ...[more]

PMID: 23097281

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