STRUCTURE OF [Sn(2-Se-C5H4N)2.l5(SPh) 1.85]: AN X-RAY CRYSTALLOGRAPHIC STUDY SUPPORTED BY CHEMICAL AND 1l9Sn NMR SPECTROSCOPIC DATA. Jagadese J. Vittal, Philip A. W. Dean, Department of Chemistry, University of Western Ontario, London, Ontario N6A 5B7, Canada
Yellow crystalline Sn(2-Se-C5H4N)2.15(SPh)1.85 (1) has been shown by 1l9Sn NMR spectroscopy to contain both Sn(2-Se-C5H4N) 2 (SPh) 2 and Sn(2-Se-C5H4N) 3 (SPh). The crystal and molecular structure of 1 has been determined by single crystal X-ray diffraction techniques. Crystal data: monoclinic, space group P2l/n, a = 9.795(2) Å, b = 22.355(4) Å, c = 11.362(2) Å, [[beta]] = 108.873 deg., V = 2354.2(8) Å3, dcalc = 1.837 g cm-3, dobs = 1.87(5) g cm-3, Z = 4, R1 = 0.0306, wR2 = 0.0651 for 2756 data (I >= 2[[sigma]](I)) and 258 parameters. Crystallographic evidence for the presence of co-crystallized Sn(2-Se-C5H4N)3(SPh) occurs only in a minor lengthening of one of the two Sn-S bonds, Sn(l)-S(l) (compared with expectation for pure Sn(2-Se-C5H4N)2(SPh)2), and an excess of electron density at S(1) when the data are modelled as Sn(2-Se-C5H4N)2(SPh) 2. These effects are attributed to a crystallographic disorder of SPh and [[eta]]l-{2-Se-C5H4N} at the S(l)Ph site, involving isostructural Sn([[eta]]2-{2-Se-C5H4N} )2 ({[[eta]]1-{2-Se-C5H4N} )(SPh) and Sn ([[eta]]2-{2-Se-C5H4N} )2(SPh)2.