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Regio- and stereoselective Ni-catalyzed 1,4-hydroboration of 1,3-dienes: access to stereodefined (Z)-allylboron reagents and derived allylic alcohols.

ABSTRACT: A catalytic regio- and stereoselective 1,4-hydroboration of 1,3-dienes was accomplished with pinacolborane in the presence of Ni(cod)(2) and PCy(3). This reaction exhibits broad substrate scope operating on a range of substituted dienes and occurs with generally high levels of selectivity and efficiency. Reactivity patterns suggest that the reactive conformation of the diene is the S-cis form. The intermediate allylboronate can be oxidized to stereodefined allylic alcohols or can be used in stereoselective carbonyl addition reactions.

SUBMITTER: Ely RJ

PROVIDER: S-EPMC2858638 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Regio- and stereoselective Ni-catalyzed 1,4-hydroboration of 1,3-dienes: access to stereodefined (Z)-allylboron reagents and derived allylic alcohols.

Ely Robert J RJ Morken James P JP

Journal of the American Chemical Society 20100301 8

A catalytic regio- and stereoselective 1,4-hydroboration of 1,3-dienes was accomplished with pinacolborane in the presence of Ni(cod)(2) and PCy(3). This reaction exhibits broad substrate scope operating on a range of substituted dienes and occurs with generally high levels of selectivity and efficiency. Reactivity patterns suggest that the reactive conformation of the diene is the S-cis form. The intermediate allylboronate can be oxidized to stereodefined allylic alcohols or can be used in ster ...[more]

PMID: 20136142

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