Synthesis and single crystal structures of first examples of tridentate ligands of (Te, N, S) type and their complexes with palladium(II), platinum(II) and ruthenium(II)
作者:P. Raghavendra Kumar、Shailesh Upreti、Ajai K. Singh
DOI:10.1016/j.ica.2007.09.012
日期:2008.4
The First examples of (Te, N, S) type ligands, 2-CH3SC6H4CH=NCH2CH2TeC6H4-4-OCH3 (L-1) and 2-CH3SC6H4CHNHCH2CH2TeC6H4- 4-OCH3 (L-2), and their metal complexes, [PdCl(L-1)]PF6 center dot CHCl3 0.5H(2)O (4), [PtCl(L-1)] PF6 (5), [PdCl(L-2)] ClO4 center dot CHCl3 (6), [PtCl(L-2)] ClO4 (7), and [Ru(p-cymene)(L-2)](PF6)(2) center dot CHCl3 (8), have been synthesized and characterized. The single crystal structures of 4, 6 and 8 have revealed that both the ligands coordinate in them in a tridentate ( Te, N, S) mode. The geometry around Pd in both the complexes has been found to be square planar, whereas for Ru in a half sandwich complex 8, it is found to be octahedral. Between two molecules of 4 there are intra and inter molecular weak Te center dot center dot center dot Cl [ 3.334(3) and 3.500(3) A, respectively] interactions along with weak intermolecular Pd center dot center dot center dot Te [3.621(2) angstrom] interactions. The Pd-Te bond lengths are between 2.517(6) and 2.541(25) angstrom and the Ru-Te bond length is 2.630(6) angstrom. The crystal structure of [ PdCl2(4-MeO-C6H4-TeCH2CH2NH2)] ( 9) is also determined. It is formed when KPF6 is not added in the synthesis of 4 and Pd-complex of L-1 is recrystallized. Apart from Te center dot center dot center dot Cl secondary interactions, C-H center dot center dot center dot pi interactions also exist in the crystal of 9. (c) 2007 Elsevier B. V. All rights reserved.