The Synthesis and Structures of Tris(2-pyridylseleno)methyl Zinc Compounds with κ2-, κ3-, and κ4-Coordination Modes

Abstract

Tris(2-pyridylseleno)methane, [Tpsem]H, has been employed to synthesize the bis(trimethylsilyl)amido zinc complex [κ3-Tpsem]ZnN(SiMe3)2. The latter compound provides access to a variety of other [Tpsem]ZnX derivatives, which include the isocyanate complex [κ4-Tpsem]ZnNCO, the hydrosulfido complex [κ3-Tpsem]ZnSH, the sulfido complex {[κ3-Tpsem]Zn}2(μ-S), the 2 : 1 complex [κ2-Tpsem]2Zn and the pyridyl-2-selenolate complex [κ4-Tpsem]Zn-(κ2-SeC6H4N), thereby demonstrating that the [Tpsem] ligand can exhibit κ2-, κ3-, and κ4-coordination modes. Variable-temperature 1H NMR spectroscopic studies demonstrate that [κ3-Tpsem]ZnN(SiMe3)2, [κ3-Tpsem]ZnSH, and {[κ3-Tpsem]Zn}2(μ-S) are fluxional on the NMR timescale.