Function of an N-heterocyclic carbene ligand based on concept of chiral mimetic.

Chem Pharm Bull (Tokyo)

Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan.

Published: November 2006

Function of a new N-heterocyclic carbene ligand based on the concept of a chiral mimetic is described. With (4R,5R)-4,5-diphenyl-1,3-dialkyl-4,5-dihydro-3H-imidazol-1-ium tetrafluoroborates as N-heterocyclic carbene precursors, Rh-catalyzed enantioselective arylation (up to 27% ee) of aromatic aldehydes with arylboronic acids and Pd-catalyzed enantioselective intramolecular alpha-arylation (up to 66% ee) of N-(2-bromoaryl)-N-alkyl-2-arylpropanamides are investigated.

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http://dx.doi.org/10.1248/cpb.54.1576DOI Listing

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