Synthesis of Heteroleptic Tin(II) and Lead(II) Compounds from Pyrazyl-Linked Bisphosphoranoimine

The synthesis and characterization of a series of tin(II) and lead(II) heteroleptic compounds derived from a novel pyrazyl-linked bisphosphoranoimine, 2,3-C4H2N2[(CH2)iPr2PN(SiMe3)]2 (1), are reported. The reaction of 1 with 2 equiv of M[N(SiMe3)2]2 (M = Sn, Pb) afforded the dinuclear heteroleptic compounds [(Me3Si)NSn(L)SnN(SiMe3)] (L = {2,3-C4H2N2[(CH)iPr2PN(SiMe3)]2}2−) (2) and {Pb[N(SiMe3)2][N(SiMe3)PPri2CH]-2,3-C4H2N2-[Pb(CHiPr2PNSiMe3)][N(SiMe3)2]} (3), respectively. Dilithium compound [Li(L)(THF)2] (4) obtained from the reaction of 1 with 2 equiv of nBuLi was used to prepare tin(II) metallacycle [Sn(CHiPr2PNSiMe3)2-2,3C4H2N2] (5) and heteroleptic compound [ClSn(L)SnCl] (6), respectively. Compounds 2−6 have been characterized by X-ray structural analysis.