Studies on Long-range Couplings between 77Se and 13C in Some Aryl Selenides, Dichlorides, and Selenoxides. The Inverse Effect on Couplings in the Selenoxide Formation

Abstract

Abstract Long-range coupling constants between 77Se and 13C in selenoanisole, diphenyl selenide, diphenyl diselenide, and their 2-mono- and 2,2′-disubstituted derivatives, selenoxanthone, selenanthrene, dichlorides, and selenoxides were measured to disclose predominant factors governing the magnitude of the coupling. Extraordinary large values for two- and three-bond couplings are found in selenoxanthone. Three factors are operative: the orientational effect, the coordination number, and the effect of ring formation. The last factor accompanies a stronger inverse effect on the coupling of selenoxides than on that of selenides.