The chemistry of rhenium alkyls. Part I. Synthesis and properties of oxorhenium(VI) methyl and trimethylsilylmethyl compounds

Abstract

The interaction of [ReO(Cl)₃(PPh₃)₂] and [ReOCl₄] with methyl-lithium forms the paramagnetic d¹ complex [ReOMe₄]. Interaction of [ReO(Cl)₃(PPh₃)₂] with Me₃SiCH₂MgCl gives the blue paramagnetic [ReO(CH₂SiMe₃)₄] and the diamagnetic [Re₂O₃(CH₂SiMe₃)₄]. Both oxotetra-alkyl compounds are thermally very stable; although [ReOMe₄] is air-sensitive, [ReO(CH₂SiMe₃)₄] is unaffected by air. E.s.r. and electronic absorption spectra (reported separately) and i.r. spectra are consistent with a square-based pyramidal structure for the oxotetra-alkyls. The i.r. spectrum of [Re₂O₃(CH₂SiMe₃)₄] is consistent with a structure containing linear Re–O–Re and cis ReO groups.