Organoselenium compound for the introduction of selenium into molecules. Prepn: N. Y. Derkach et al., Zh. Org. Khim. 7, 1543 (1971); and use: D. Liotta et al., Tetrahedron Lett. 1978, 5091. Improved synthesis: N. Miyoshi et al., Synthesis 1979, 300. Synthetic applications: S. D. Rychnovsky, D. J. Skalitzky, Synlett 1995, 555; H. Abe et al., Chem. Pharm. Bull. 46, 1311 (1998); M. W. DeGroot, J. F. Corrigan, Dalton 2000, 1235. Brief review: M. David, Synlett 2001, 445.