Highly enantiomerically enriched planar chiral naphthalene tricarbonylchromium complexes

Chem Asian J. 2006 Sep 18;1(3):459-68. doi: 10.1002/asia.200600106.

Abstract

Lithiation/electrophile trapping reactions were carried out with the highly enantiomerically enriched complex [Cr(5-bromonaphthalene)(CO)3]. Electrophile quenching with ClPPh2, PhCHO, and (Me3SiO)2 afforded the enantiomerically enriched (>97% ee) planar chiral 5-substituted naphthalene complexes with PPh2, CH(Ph)OH, and OH substituents, respectively. Very mild Pd-catalyzed Suzuki-Miyaura cross-coupling reactions were developed and applied to the highly labile [Cr(5-bromonaphthalene)(CO)3] to give nine new planar chiral aryl-, heteroaryl-, alkynyl-, and alkenylnaphthalene chromium complexes with high enantiomeric purity. The efficient ambient-temperature coupling reactions with borinates prepared in situ were also applied to a number of chlorobenzene complexes and to aryl and vinyl halides.