title: Direct synthesis of doubly deprotonated, dearomatised lutidine PNP Cr and Zr pincer complexes based on isolated K and Li ligand transfer reagents.
abstract: Double deprotonation of 2,6-bis-(di-tert-butylphosphinomethyl)-pyridine ((tBu)PN(tBu)P), with KCH2C6H5 afforded K2((tBu)P*Na(tBu)P*), Na = anionic amido N, (tBu)P* = di-tert-butyl vinylic P donor. The analogous [Li2((tBu)P*Na(tBu)P*)]2 (1) was reacted with [CrCl2(THF)2] and [ZrCl4(THT)2] to give the helical [Cr{Cr((tBu)P*Na(tBu)P*)Cl}2] (2) and [Zr((tBu)P*Na(tBu)P*)Cl2] (3), respectively. DFT calculations support dearomatisation of P*NaP* and its high donor ability.
authors.affiliation: Laboratoire de Chimie de Coordination, Institut de Chimie (UMR 7177 CNRS), Université de Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Simler
authors.forename: Gilles
authors.initials: G
authors.lastname: Frison
authors.forename: Pierre
authors.initials: P
authors.lastname: Braunstein
authors.forename: Andreas A
authors.initials: AA
authors.lastname: Danopoulos