Dynamic NMR study of tri-tert-butylcarbinol and of a carbinol-methylaluminoxane mixture

Abstract

The reaction of tri‐tert‐butylcarbinol and oligomeric methylaluminoxane (MAO) prepared in toluene‐d8 was studied by analysing the reaction mixture utilizing ROESY, HSQC and HMBC 2D NMR experiments. The formation of one main alkoxide was observed in the reaction. Dynamic 13C NMR and semiempirical PM3 molecular modelling were used in concert to study the tert‐butyl group rotation barriers of this alkoxide. From several modelled acyclic and cyclic MAO fragments, an open chain—Al(Me)OAl(Me)—fragment was observed to be consistent with the NMR results. Copyright © 2000 John Wiley & Sons, Ltd.