Chemistry of Four-Membered Ring Compounds Containing a Hypervalent Sulfur Atom and a Heteroatom at the Neighbor Positions

Abstract

Title compounds containing tetracoordinated and pentacoordinated sulfur together with oxygen, nitrogen, or sulfur were successfully synthesized as stable compounds. They contain the Martin ligand, which is well known to be able to stabilize such highly coordinated main group compounds. X-ray crystallographic analyses revealed that they have distorted trigonal bipyramidal (TBP) or pseudo-TBP structures. In marked contrast to group 13–15 element analogues, which afford the corresponding alkenes upon heating, thermolyses of compounds bearing an oxygen or nitrogen atom gave the corresponding oxiranes or aziridine, suggesting the possibility that these compounds are intermediates of the Corey-Chaykovsky reaction of sulfur ylides with carbonyl compounds or imines. Thermolysis of 1λ⁴,2-dithietanes also gave the corresponding thiiranes. The stereochemistry (retention of configuration) of formation of these three-membered ring compounds is also described.

Keywords:

• 1λ⁴,2-Dithietanes
• four-membered heterocyclic compounds
• highly coordinated compounds
• highly coordinated 1,2-oxathietane
• hypervalent compounds
• Martin ligand
• 1,2-oxathietanes
• sulfuranes
• thermolysis
• 1λ⁴,2-thiazetidines
• three-membered ring formation reaction
• X-ray crystallographic analysis

Acknowledgments

This work was partially supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan and the 21 Century and Global COE Programs. The author thanks Professor R. Okazaki for his helpful discussions and useful advice. He is grateful to Professor N. Tokitoh and Associate Professor N. Kano for the X-ray crystallography. The author thanks all coauthors of these works for their experimental work and thanks Central Glass, Tosoh Finechem Corporation, and Shin-etsu Chemicals Co., Ltd., for gifts of organofluorine compounds, alkyllithiums, and organosilicon compounds, respectively.