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Enantioselective homocrotylboration of aliphatic aldehydes.

ABSTRACT: A practical route to optically pure syn-homocrotylation reagents is described, including highly diastereo- and enantioselective preparation of numerous syn-homocrotyl products, as well as several matched mismatched pairs. NMR experiments suggest that the active homocrotylating species is a cyclopropylcarbinyldichloroborane generated by chloride exchange from the PhBCl(2) activator. Computational studies support the intermediacy of chloroboranes and suggest that homoallyl/homocrotyl transfers occur through Zimmerman-Traxler transition states.

SUBMITTER: Lin H

PROVIDER: S-EPMC3560844 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Enantioselective homocrotylboration of aliphatic aldehydes.

Lin Hongkun H Pei Wenbo W Wang Hao H Houk Kendall N KN Krauss Isaac J IJ

Journal of the American Chemical Society 20121226 1

A practical route to optically pure syn-homocrotylation reagents is described, including highly diastereo- and enantioselective preparation of numerous syn-homocrotyl products, as well as several matched mismatched pairs. NMR experiments suggest that the active homocrotylating species is a cyclopropylcarbinyldichloroborane generated by chloride exchange from the PhBCl(2) activator. Computational studies support the intermediacy of chloroboranes and suggest that homoallyl/homocrotyl transfers occ ...[more]

PMID: 23256566

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