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.
在
硒基
苯甲醚、二苯
硒、二苯二
硒及它们的2-单取代和2,2'-双取代衍
生物、
硒黄酮、
硒蒽、二
氯化物和
硒氧化物中,测量了77Se与13C之间的远程耦合常数,以揭示影响耦合强度的主要因素。在
硒黄酮中发现了异常大的双键和三键耦合值。三个因素在起作用:取向效应、配位数和环的形成效应。最后一个因素对
硒氧化物的耦合具有比对
硒化物更强的逆效应。