Synthesis of an acyclic diselenodithioether ligand tethered with bulky substituents and its application to the synthesis of a distorted octahedral palladium(II) complex

Abstract

A new o-phenylene-bridged diseleno

Acyclic tetrachalcogenoether ligands tethered with bulky substituents: Their syntheses and coordination chemistry

“…These results suggested that complex 8 in solution had a four-coordination structure, where the two inner selenium atoms of 8 and two chorine atoms coordinated to the palladium metal. These trends in the terminal selenium atoms were also observed for complex 6 (Scheme 3) [8].…”

“…Synthesis of 1,2-bis(2-chalcogenaphenylselanyl)benzene ligands 3 and 4 1,2-Bis(2-chalcogenaphenylselanyl)benzene ligands 3 and 4, in which two or all sulfur atoms in ligand 1 were replaced with selenium atoms, were synthesized via diselenides 11 or 12 (Scheme 1). Although the synthesis of 1 and 2, bearing sulfur atoms at inner positions, were achieved directly by the reactions of 9 or 10 with benzene-1,2-dithiol [7,8], we selected different methods for 3 and 4 due to the difficulty in the synthesis of benzene-1,2-diselenol [9]. Diselenides 11 and 12 were obtained in moderate yields by the reaction of 9 and 10 with t-BuLi and then with an excess amount of elemental selenium followed by the treatment with LiAlH 4 , water and air [10].…”

“…The distances between the terminal chalcogen and the palladium atoms [7: PdÁ Á ÁS(t) = 3.2309(9) Å , 8: PdÁ Á ÁSe(t) = 3.1934(2) Å ] are shorter than the sum of the van der Waals radii of palladium and sulfur atoms (3.43 Å ) or that of palladium and selenium atoms (3.53 Å ), respectively. This result suggests that complexes 7 and 8 have weak interactions between the palladium and the terminal chalcogen atoms leading to the pseudo six-coordinate structure in the crystalline state as well as the complexes 5 and 6 [7,8] (see Table 2). …”

“…Elemental analyses were performed at the Microanalytical Laboratory of the Institute for Chemical Research, Kyoto University. Tbt-substituted sulfide (9) [7] and selenide (10) [8] were prepared according to the reported procedure.…”

“…Recently, we have succeeded in the syntheses of the acyclic tetrachalcogenoether ligands 1 and 2, bearing an extremely bulky substituent, 2,4,6-tris[bis(trimethylsilyl)-methyl]phenyl (Tbt) group, at both terminal chalcogen atoms, and their dichloropalladium(II) complexes 5 and 6, respectively [7,8]. These complexes had a pseudo sixcoordinate structure, in which the central two chalcogen atoms in tetrachalcogenoether ligand and two chlorine atoms were arranged in a square planar fashion around 0022-328X/$ -see front matter Ó 2008 Elsevier B.V. All rights reserved.…”