title: Synthesis, structures and ab initio studies of selenium and tellurium bis(carbodithioates and carbothioates).
abstract: A series of selenium and tellurium bis(carbodithioates and carbothioates) were synthesized. X-Ray structure analysis revealed that Se(SSCC(6)H(4)OMe-2)(2), Te(SSCC(6)H(4)OMe-2)(2) and Te(SSCC(6)H(4)Me-4)(2) have trapezoidal-planar configuration of ES(4) (E = Se, Te) and despite the larger atomic radii, the C=S···Te distances in Te(SSCC(6)H(4)OMe-2)(2) are comparable to those in the corresponding selenium derivatives Se(SSCC(6)H(4)OMe-2)(2). Molecular-orbital calculations performed on compounds E(E'SCR)(2) (E = S, Se, Te; E' = O, S; R = Me, Ph, C(6)H(4)OMe-2) showed that the syn-conformers of Se(SSCR)(2) and Te(SSCR)(2) are more stable than the corresponding anti-ones, while, in the case of carbothioic acid derivatives, E(SOCR)(2) showed that their anti-conformers are all more stable than the corresponding syn-ones. Natural bond orbital (NBO) analyses of these dithio-compounds revealed that two types of orbital interactions, n(S(1))→σ*(E-S(2)) and n(O)→σ*(E-S(2)), play a role in the bonding of E[S(2)S(1)CC(6)H(4)OMe-2](2) (E = Se, Te) and the former play a particularly predominant role.
authors.affiliation: Department of Applied Chemistry, School of Engineering, Chubu University, Kasugai, 487-8501, Japan. kshinzi@nifty.com
authors.forename: Shinzi
authors.initials: S
authors.lastname: Kato
authors.forename: Kazuyasu
authors.initials: K
authors.lastname: Tani
authors.forename: Masaru
authors.initials: M
authors.lastname: Ishida
authors.forename: Junko
authors.initials: J
authors.lastname: Nonogaki
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ebihara
authors.forename: Satoko
authors.initials: S
authors.lastname: Hayashi
authors.forename: Waro
authors.initials: W
authors.lastname: Nakanishi
authors.forename: Osamu
authors.initials: O
authors.lastname: Niyomura
authors.forename: Fumio
authors.initials: F
authors.lastname: Ando
authors.forename: Jugo
authors.initials: J
authors.lastname: Koketsu