Abstract
Chemistry of thio-and selenoaldehydes has been reviewed focusing on advances in 1980's. The methods for the formation of thio-and selenoaldehydes are roughly divided into five types : (1) Norrish type II photoreaction of α-ketosulfides, (2) 1, 5-sigmatropic reactions of thiosulfinates and thioseleninates, (3) 1, 2-eliminations, (4) retro-Diels-Alder reactions of cycloadducts, and (5) reaction of organometallics with calcogenoformates. Thioaldehydes as reactive intermediates are generated mainly by methods (1) - (4), while stable thioaldehydes are synthesized by method (5) or thermolysis of polymer (RCHS) n. Any stable selenoaldehyde is yet unknown, but those as reactive intermediates can be formed by methods (3) - (5). Although a variety of reactions of thioaldehydes have ben studied using both reactive and stable species, those of selenoaldehydes have been so far limited almost exclusively to cycloadditions. Synthesis and reactions of metal complexes of thio- and selenoaldehydes are also briefly reviewed.
