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Late-stage diversification of chiral N-heterocyclic-carbene precatalysts for enantioselective homoenolate additions.

ABSTRACT: A library of chiral triazolium salts has been prepared by late-state diversification of a triazolium amine salt. By utilizing a primary amine as a functional handle, a single triazolium salt can be transformed into a variety of chiral N-heterocyclic carbene precatalysts. This approach makes the preparation of chiral N-heterocyclic carbenes possible by a single-step modification of a triazolium salt, rather than the usual need for multistep organic synthesis and challenging heterocycle formation for each member of a catalyst library. We have screened these catalysts for control of diastereo- and enantioselectivity in a ?-lactam-forming reaction between ?,?-unsaturated aldehydes and cyclic ketimines.

SUBMITTER: Zheng P

PROVIDER: S-EPMC3179768 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Late-stage diversification of chiral N-heterocyclic-carbene precatalysts for enantioselective homoenolate additions.

Zheng Pinguan P Gondo Chenaimwoyo A CA Bode Jeffrey W JW

Chemistry, an Asian journal 20101222 2

A library of chiral triazolium salts has been prepared by late-state diversification of a triazolium amine salt. By utilizing a primary amine as a functional handle, a single triazolium salt can be transformed into a variety of chiral N-heterocyclic carbene precatalysts. This approach makes the preparation of chiral N-heterocyclic carbenes possible by a single-step modification of a triazolium salt, rather than the usual need for multistep organic synthesis and challenging heterocycle formation ...[more]

PMID: 21254434

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