The chemistry of the indoleninones. III. Reactions of 2-(Methylthio)indoleninones with diazomethane

Abstract

The reactions of 2-(methy1thio)indoleninone [2-(methylthio)-3H-indol-3-one] and its 4-bromo and 6-bromo derivatives with diazomethane lead to the appropriate 2-(methylthio)spiro[3H-indole-3,2'- oxirans] and 3-methoxy-2-(methy1thio)quinolines in relative yields dependent upon the steric in- fluence of bromine when in the 4-position. P.m.r. studies on the 2-(methylthio)spiro[3H-indole-3,2'-oxirans] reveal a marked solvent depen- dence on the chemical shift values of the non-equivalent protons of the methylene group in the oxiran ring.