Reactions between organoaluminium compounds and N-substituted acid amides

Abstract

Reactions between R¹₃Al and R²NH·CO·R³(R¹= Me or Et; R²= Me, Et, Bu^t, or Ph; R³= Me or Ph) leading to materials (R¹₂Al·NR²·CO·R³)_n are described. I.r., mass, and ¹H n.m.r. spectroscopic details of the products are given. Cyclic 8-membered ring structures (n= 2) are proposed for these compounds in the solution phase. Cryoscopic studies support dimeric structures for the compounds (Me₂Al·NPh·CO·Me)₂ and (Me₂Al·NBu^t·CO·Me)₂ in benzene, although an X-ray crystallographic study of the former, which can also be prepared from Me₃Al and PhNCO, shows a trimeric structure to be more likely in the crystal. The related sulphur compound Me₂Al·NPh·CS·Me, from Me₃Al and PhNCS, probably also has a similar cyclic structure in solution.