Synthesis and reactivity of N,N'-bis

Article abstract of DOI:10.1016/0022-328X(94)88135-9

The condensation of a racemic mixture of 2,2'-diamino-1,1'-binaphthylene with two equivalents of o-(diphenylphosphino)benzaldehyde gives a racemic mixture of N,N'-bisI and Ag^I has been explored.The interaction of I with one equivalent of Cu(Ph3P)2Br and in CH2Cl2 gives Cu(Binap-P2N2)Br (II) and (III) in 60percent and 74percent yield, respectively.In II the Binap-P2N2 ligand acts as a tridentate chelating agent, with the two phosphino groups and one of the two imino groups coordinated to the Cu, whereas in III it acts in tetradentate chelating mode.A variable temperature 31P<1H> NMR study of II reveals that the coordinated and the uncoordinated imino groups of the tridentate Binap-P2N2 ligand undergo a facile intramolecular exchange even at -55 deg C.The interaction of I with one equivalent of AgBF4 in CH2Cl2 gives (IV) in 79percent yield.In IV, the Binap-P2N2 ligand acts as a tridentate chelating agent, with the two phosphino groups and one of the two imino groups coordinated to the Ag.The structure of IV has been established by an X-ray diffraction study.The distance between Ag and N(2) is 2.56(1) Angstroem, and the non-bonding distance between Ag and N(1) is > 3.0 Angstroem.Key words: Silver; Copper; Imine; Multidentate ligands; Crystal structure