Heterocyclic synthesis sulfur transfer reagents

Thionyl chloride (SOCl2) is the most versatile of all sulfur transfer reagents in heterocyclic synthesis. The sulfur-oxygen bond renders the sulfur atom more electrophilic the possibility of ready removal by elimination of the oxygen atom allows easy aromatization of many of the initially formed sulfur heterocycles. Two general reviews of the chemistry of thionyl chloride are available.53 Both cover the literature up to about 1970. 

The remaining four chapters of the present volume involve topics new to the series. Two of them deal with specific groups of compounds (C. J. Moody on Azodicarbonyl Compounds and T. Sasaki on Heteroada-mantanes ) and two others deal with the Use of Transition Organome-tallic Compounds in Heterocyclic Synthesis (J. L. Davidson and P. N. Preston) and Sulfur Transfer Reagents (M. Davis). 

Recent Advances in the Chemistry of Benzisothiazoles and Other Polycyclic Isothiazoles, 38, 105 Sulfur Transfer Reagents in Heterocyclic Synthesis, 30, 47. 

The use of other phosphorus-sulfur reagents for heterocyclic synthesis appears rare. It would be interesting to investigate in more detail the reaction of compounds, such as the phosphine sulfides, with organic substrates. Triphenylphosphine sulfide is an effective sulfur transfer agent, as it converts oxiranes into thiiranes in good yield. The reaction proceeds with retention of configuration.128... 

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