Reactions between oximes and organo-derivatives of group III elements. Part I. Acetoxime

Abstract

Acetoxime reacts at 100° with trimethylborane to form methane and (Me₂C:NOBMe₂)_n, which is monomeric (n= 1) in the gas phase, partially associated (n= 1·3–1·4) in benzene solution, and probably dimeric in the crystal phase. A six-membered “BONBON” ring structure seems likely for this compound, although a four-membered “BOBO” ring cannot be ruled out on present evidence. Trimethyl-aluminium, -gallium, and -indium react with acetoxime at –78° to form related compounds (Me₂C:NOMMe₂)₂(M = Al, Ga, or In), which are thought to be dimeric in the gas, solution, and crystal phases and to contain similar rings. Trimethylthallium at room temperature gives the analogous derivative Me₂C:NOTlMe₂. Methyl-lithium and acetoxime give the polymeric Me₂C:NOLi. The mass i.r., and ¹H n.m.r. spectra of these compounds are discussed, the latter showing a remarkable solvent effect. Reaction between diborane and acetoxime leads to general decomposition.