C 4H 3SSeCH 2CH 2OC 6H 5: synthesis, characterization and reaction with palladium(II) and nickel(II)

Abstract

ThSeCH 2CH 2OPh (Th=2-thienyl, C 4H 3S-; Ph=phenyl) ( 2) has been prepared by the reaction of BrCH 2CH 2OPh ( 1) and ThSeLi. The compound was characterized by 13C{ 1H}- and 77Se-NMR spectroscopy and X-ray crystallography. 2 is monoclinic, space group P2 1/ c, a=10.865(2), b=5.152(1), c=41.996(8) Å, β=92.20(3)°. All bond lengths and angles are quite normal as exemplified by the respective SeC(alkyl) and SeC(aryl) bonds of 1.957(6)–1.966(6) and 1.901(7)–1.905(7) Å. The lattice is composed of discrete molecules that are joined together by weak hydrogen bonds into a three-dimensional network. Upon treating ThSeCH 2CH 2OPh with [PdCl 2(NCPh) 2] and [NiCl 2(PPh 3) 2] in benzene, a dinuclear palladium complex [Pd 2Cl 2(μ-Cl)(μ-SeTh)(PPh 3) 2] ( 3) and a mononuclear complex [PdCl 2(PPh 3) 2] ( 4) were formed together with a precipitation of NiCl 2. The X-ray quality crystals were recrystallized in CH 2Cl 2. 3·2.5CH 2Cl 2 is monoclinic, space group C2/ c, a=32.907(7), b=14.545(3), c=22.433(5) Å, β=114.37(3)° and contains a novel asymmetrical arrangement of one bridging chlorido and thienylselenolato ligand. Both palladium atoms show an square-planar coordination. The terminal PdCl bond lengths are 2.388(1) and 2.346(1) Å with slightly longer distances of 2.418(1) and 2.450(1) Å involving the bridging chlorido ligand. The PdSe distances are 2.4092(9) and 2.4376(7) Å.