Stereoselective Synthesis of the Axially Chiral A−B Ring System of Vancomycin Utilizing a Planar Chiral Arene Chromium Complex

[reaction: see text] The axial biaryl ring system of vancomycin was stereoselectively synthesized by utilizing a planar chiral tricarbonyl(arylhalide)chromium complex. Both enantiomers of the planar chiral (arylbromide)chromium complexes, (+)-9 and ent-(-)-9, can be stereoselectively transferred to an absolutely identical key intermediate 23 for the vancomycin A-B ring system by the diastereoselective Suzuki-Miyaura cross-coupling reaction as key step.