77Se, 13C and 1H NMR investigations on ortho-carbonyl benzeneselenenyl derivatives

o-Carbonyl benzeneselenenyl compounds with COCH₃, CHO and COOCH₃ as carbonyl functions and SeCl, SeBr, SeSCN, SeSeCN, SeCN and SeCH₃ as selenium-containing groups, have been studied by ¹H, ¹³C and ⁷⁷Se NMR spectroscopy. The IR CO stretching frequencies of these compounds are also reported. If the SeCH₃ derivatives are excluded, the compounds mainly adopt a planar ‘cis’ conformation, due to an interaction between the CO group and the selenium atom. The range of over 800 ppm for the observed ⁷⁷Se chemical shifts makes ⁷⁷Se NMR spectroscopy a powerful tool for physical organic chemists.