Nitrones and Oxaziridines. XXVI. Reaction of Grignard Reagents with 3-Oxo-1-pyrroline 1-Oxides and Synthesis of 2H-Pyrrole 1-Oxides

Abstract

Alkyl-, benzyl-, allyl- and vinyl-magnesium halides undergo selective addition to the carbonyl group of 2-phenyl- and 2-t-butyl-3-oxo-1-pyrroline 1-oxides (1a,b) to afford a range of alcohols. These can be dehydrated easily to form 2H-pyrrole 1-oxides (3) or 3-alkylene- or 3-arylmethylene-1-pyrroline 1-oxides (4) depending on the precise structural features involved in each case. Phenylmagnesium bromide underwent addition only to the oxo nitrone (la) and failed to react with (1b).