A. J. Boyd, D. Boyd, M. G. Burnett
1988
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0
Influential Citations
1
Citations
Journal
Journal of The Chemical Society-perkin Transactions 1
Abstract
The dinitrone derivatives (5a, b) of 2,2,4,4-tetramethylcyclobutane-1,3-dione were synthesised by peroxyacid oxidation of the corresponding di-imines (3a, b). X-Ray crystallographic analysis of di-imine (3a) and the hydroxyimino nitrone isomers (6a, b) indicate a marked buttressing effect leading to an exclusive preference for the trans geometry in di-imine (3a) and dinitrone (5a). Thermal elimination reactions of the N-But substituted nitrones (5a), (6a), and (8a) to yield oximes and 2-methylpropene have been investigated by u.v. kinetic studies. The results are consistent with a concerted mechanism involving a five-membered cyclic transition state.