title: Facile formation and redox of benzoxazole-2-thiolate-bridged dinuclear Pt(II/III) complexes.
abstract: Reaction of [Pt(L)(μ-Cl)](2) (L = ppy (2-phenylpyridine) or bzq (benzo[h]quinoline)) with 2-mercaptobenzoxazole (NOSH) and NaOAc in THF at r.t. yields the dinuclear Pt(II) d(8)-d(8) complexes [Pt(2)L(2)(μ-NOS-κN,S)(2)] (L = ppy, 1; L = bzq, 2) and the Pt(III) d(7)-d(7) complexes [Pt(2)(ppy)(2)(μ-NOS-κN,S)(2)(NOS-κS)(2)] (L = ppy, 3; L = bzq, 4) in one pot. The C,N-cyclometalated ligand is chelating whereas the N,S-donating benzoxazole-2-thiolates doubly bridge the two metal centers. The Pt···Pt separations of 3.0204(3) and 2.9726(8) Å in 1 and 2 contract to 2.685(1) Å in 3 and 2.6923(3) Å in 4, respectively, when two S-bound thiolate ligands coordinate trans- to the Pt···Pt axis. However, cyclometalation is preserved and there is minimum perturbation of the bridging ligands. Complexes 3 and 4 can be also obtained by oxidative addition of the thiolate ligand. In the presence of NaBH(4), 3 and 4 can be reduced to 1 and 2, respectively. At r.t., 1 and 2 exhibit intense orange-red luminescence at 625 nm and 631 nm, respectively. The electrochemical properties of 1-4 have been also discussed.
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.forename: Lu
authors.initials: L
authors.lastname: Jiang
authors.forename: Zhi-Pan
authors.initials: ZP
authors.lastname: Liu
authors.forename: C R Raymond
authors.initials: CR
authors.lastname: Gan
authors.forename: Zhaolin
authors.initials: Z
authors.lastname: Liu
authors.forename: Xin-Hai
authors.initials: XH
authors.lastname: Zhang
authors.forename: Jin
authors.initials: J
authors.lastname: Zhao
authors.forename: T S Andy
authors.initials: TS
authors.lastname: Hor