Synthesis of sulphur-containing heterocycles by ring closing diene metathesis

Abstract

We have shown that, surprisingly, the Schrock molybdenum alkylidene catalyst 1 can perform ring closing metathesis reactions on substrates containing a sulphide group, converting diallyl sulphide 5 to 2,5-dihydrothiophene 6 with >99 % conversion. By contrast, the ruthenium alkylidene catalyst 2, which is generally more tolerant of functional groups in the substrate, is unreactive towards diallylsulphide. However even the molybdenum catalyst 1 proved unable to catalyse ring closure of tetrathiafulvalene derivative 7.