Facile Synthesis of 3-Aroyl-3-Sulfolenes Through Cycloadditions of Arylnitrile Oxides & 3-Sulfolene

Abstract

3-Sulfolene undergoes [2+3] cycloadditions with arylnitrile oxides to yield the corresponding 2-isoxazolines which on cleavage in the presence of Mo(CO)₆ followed by dehydration gave 3-aroyl-3-sulfolenes in moderate yields.

Notes

Spectral data of cycloadduct(3a) (R=phenyl) IR(Nujol)v _max: 1600, 1464, 1314, 1302, 1234cm^{−1 1}H NMR (300 MHz, CDCl₃) (See Table 2). MS m/z = 237 (M⁺).

Spectral data of 3-aroyl-3-sulfolene(5a) (R=phenyl) IR(CHCl₃)v _max: 2976, 1657, 1324, 1287cm^{−1 1}H NMR (300 MHz, CDCl₃): δ 7.75(m, 2H), 7.61 (m, 1H), 7.5(m, 2H), 6.73(m, 1H), 4.2(m, 2H), 4.12(m, 2H). MS m/z = 222 (M⁺).