70650-93-0Relevant articles and documents
Reactions with Aziridines, 45. - Arene Hydrides, 5 Reversibility of Carbonyl Attack on N-Benzoylaziridines Prior to Ring Opening by Carbanions. - Strong Influence of the Gegen Ion
Mall, Thomas,Stamm, Helmut
, p. 1349 - 1352 (2007/10/02)
A previous report had shown that anthracene hydride AH- or the xanthenyl anion X-, respectively, at first add to the carbonyl group of N-benzoylaziridines since high yields of benzoyl dihydroanthracene 3 or benzoyl xanthene 11 were obtained when in early stages the reaction was quenched with protons.The respective intermediate carbonyl adducts 2 and 10 had been considered to be precursors of products resulting from homolysis of the aziridine ring.It is now shown that quenching of the reaction between AH- or X- and N-benzoylaziridines 1a, b with methyl iodide or aroyl chlorides results in substantial yields of products derived from either AH- (or X-) or 1a,b.This indicates that 2 (or 10) are in equilibrium with AH- (or X-) and 1a, b.Study of the gegen ion influence with X- revealed that the equilibrium concentrations of 10-Na+ were much lower than those of 10-Li+ while simultaneously the ring opening of 1a was distinctly faster with X-Na+ than with X-Li+.This finding suggests that, contrary to the previous assumption, the equilibrium concentrations, of X- and 1a are responsibile for the (homolytic) ring opening.
