Reactions of Zinc Hydride with Silylenes: From Oxidative Addition to Ligand Exchange Reactions

Abstract

Oxidative addition reactions of the zinc hydride LZnH (L = CH[C(Me)NAr]2, Ar = 2,6-iPr2C6H3) to silylenes L1Si (L1 = ArNC(=CH2)CHC(Me)NAr, Ar = 2,6-iPr2C6H3) and L2SiNMe2 (L2 = PhC(NtBu)2) yielded L1Si(H)–ZnL (1) and LH2Si(NMe2)ZnL (3), whereas the reaction with silylene L2SiCl (L2 = PhC(NtBu)2) proceeded with H/Cl ligand exchange and the formation of the heterobimetallic complex L2Si(H)–Zn(Cl)L (2). Protonation reaction of 1 with H(OEt2)2BArF 4 (B{(3,5-CF3)2C6H3}4) gave the cationic congener LSi(H)–ZnL (4). The nature of the Zn–Si bond in 1–4 was evaluated by quantum chemical calculations, demonstrating that the Si–Zn bond in 1 and 3 represents the covalent bond, whereas those in 2 and 4 are better described as dative bonds.