Silver(i) complexes containing heteroleptic diorganochalcogen(ii) ligands

Abstract

The reaction of 4-[(CH₂O)₂CH]C₆H₄Br with n-BuLi, followed by the insertion of the chalcogen (S or Se) and in situ reaction with n-BuBr, has afforded the formation of (n-Bu){4-[(CH₂O)₂CH]C₆H₄}E [E = Se (1), S (2)]. Deprotection of the formyl groups in 1 and 2 afforded (n-Bu)[4-(CHO)C₆H₄]E [E = Se (3), S (4)], which were further used for the preparation of (n-Bu)[4-{2-C₆H₅-(4H)-oxazol-5-one}C₆H₄]E [E = Se (5), S (6)]. Compounds 3, 5 and 6 were found to be useful ligands for the silver(I) complexes [Ag{(n-Bu)[4-(OCH)C₆H₄]Se}][OTf] (7) (OTf = CF₃SO₃) and [Ag{(n-Bu)[4-{2-C₆H₅-(4H)-oxazol-5-one}C₆H₄]E}]X [X = OTf, E = Se (8), S (9); X = PF₆, E = Se (10), S (11)]. For the identification and characterization of the compounds, multinuclear NMR (¹H, ¹³C{¹H}, ¹⁹F{¹H}, ³¹P{¹H}, ⁷⁷Se{¹H}) spectroscopy, UV-Vis spectroscopy, IR spectroscopy, elemental analysis, molar conductivity measurements and mass spectrometry were used, when appropriate. The crystal structures of 5, 6 and 9 were determined by single-crystal X-ray diffraction. The formation of a 1D coordination polymer, [Ag₂(OTf)₂{(n-Bu)[4-{2-C₆H₅-(4H)-oxazol-5-one}C₆H₄]S}₂]_n, with a dinuclear core, was observed in 9.