Controlled hydrolysis of AlMe3 to tetramethylalumoxane and a new look at incipient adducts with water

Abstract

We present an efficient route to tetramethylalumoxane by the controlled hydrolysis of AlMe₃ in the presence of pyridine. The AlMe₃(pyr) hydrolysis by 0.5 and 1 equiv. of H₂O has been followed with real-time ¹H NMR. Based on high-level quantum-chemical calculations, we conclude that hypervalent, pentacoordinate aluminium species are critical in the first steps of hydrolysis.