Abstract
Novel cyclic polychalcogenides containing a variety of heavier main group elements of groups 13, 14, and 15 as ring members have been synthesized as stable crystalline compounds by taking advantage of an effective steric protection group, 2,4,6-tris[bis(trimethylsilyl)methyl]-phenyl (denoted as Tbt in this article). The molecular structures of tetrachalcogenametallolanes of group 14 elements, Tbt(R)ME4 (M = Si, Ge, Sn, and Pb; E = S, Se), and some polysulfides containing antimony or boron atom as a ring member were analyzed by X-ray crystallography to elucidate the skeletal features of these novel ring systems. Dechalcogenation reactions of these cyclic polychalcogenides with trivalent phosphorus reagents provide new and useful synthetic methods for the doubly bonded compouds between the corresponding heavier main group element and a chalcogen atom, a novel class of low-coordinate compounds in the main group element chemistry.