Synthesis, properties, and multinuclear (1H, 13C, 77Se) magnetic resonance studies of the hybrid selenide ligands o-C6H4(SeMe)Y (Y = NMe2, PMe2, AsMe2, SbMe2, OMe, and SMe)

Abstract

The reaction of o-bromophenyl methyl selenide with lithium dimethyl-phosphide, -arsenide, and -antimonide gave the seleno-phosphine o-C₆H₄(SeMe)PMe₂(2), -arsine o-C₆H₄(SeMe)AsMe₂(3), and -stibine o-C₆H₄(SeMe)SbMe₂(4) respectively. The seleno-amine o-C₆H₄(SeMe)(NMe₂)(7), -ether o-C₆H₄(SeMe)OMe (5), and -sulphide o-C₆H₄(SeMe)SMe (6) were obtained from methaneselenenyl bromide and RMgBr [R =o-C₆H₄(OMe), o-C₆H₄(NMe₂)] or o-C₆H₄(SMe)Li. The bis-selenide o-C₆H₄(SeMe)₂(8) is conveniently prepared from the polymeric selenide –(o-SeC₆H₄Se)_n, NaO₂SCH₂OH, and Mel. The o-substituted selenides have been characterised by mass spectrometry, ¹H, ¹³C, and ⁷⁷Se n.m.r. spectroscopy, and for compounds (2), (3), (4), and (8) by the preparation of quaternary derivatives. The trends in the ⁷⁷Se n.m.r. chemical shifts and coupling constants are discussed.