Reductive coupling of aromatic oxims and azines to 1,2-diamines using Zn-MsOH or Zn-TiCl4

The reduction of aromatic aldoxims and azines with Zn in the presence of MsOH or TiCl4 afforded N.N'-unsubstituted 1,2-diamines in one-step. The reductive coupling with Zn-MsOH gave meso 1,2-diamines selectively, whereas cll 1,2-diamines were formed selectively by the reduction with Zn-TiCl4. (C) 2001 Elsevier Science Ltd. All rights reserved.