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Synthesis of ?-amino acid derivatives and peptides via enantioselective addition of masked acyl cyanides to imines.

ABSTRACT: A general, asymmetric synthesis of amino acid derivatives is reported. Masked acyl cyanide (MAC) reagents are shown to be effective umpolung synthons for enantioselective additions to N-Boc-aldimines. The reactions are catalyzed by a modified cinchona alkaloid, which can function as a bifunctional, hydrogen bonding catalyst, and afford adducts in excellent yields (90-98%) and high enantioselectivities (up to 97.5:2.5 er). Unmasking the addition products gives acyl cyanide intermediates that are intercepted by a variety of nucleophiles to afford ?-amino acid derivatives. Notably, the methodology provides an alternative method for peptide bond formation.

SUBMITTER: Yang KS

PROVIDER: S-EPMC4244832 | biostudies-other | 2014 Nov

REPOSITORIES: biostudies-other

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Synthesis of α-amino acid derivatives and peptides via enantioselective addition of masked acyl cyanides to imines.

Yang Kin S KS Rawal Viresh H VH

Journal of the American Chemical Society 20141107 46

A general, asymmetric synthesis of amino acid derivatives is reported. Masked acyl cyanide (MAC) reagents are shown to be effective umpolung synthons for enantioselective additions to N-Boc-aldimines. The reactions are catalyzed by a modified cinchona alkaloid, which can function as a bifunctional, hydrogen bonding catalyst, and afford adducts in excellent yields (90-98%) and high enantioselectivities (up to 97.5:2.5 er). Unmasking the addition products gives acyl cyanide intermediates that are ...[more]

PMID: 25366558

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