title: Supramolecular Macrocyclic Pd(II) and Pt(II) Squares and Rectangles with Aryldithiolate Ligands and their Excellent Catalytic Activity in Suzuki C-C Coupling Reaction.
abstract: Addition of 1,4-benezenedithiol and 4,4'-biphenyldithiol to M(OTf)2 (M = cis-[Pt(PEt3)2](2+) or cis-[Pd(dppe)](2+)) (dppe = 1,2-bis(diphenylphosphino)ethane) gave self-assembled tetranuclear complexes [M2{S(C6H4)nS}]2(OTf)4 (n = 1, 2). The same reaction with 1,4-benezenedimethanethiol yielded octanuclear supramolecular coordination complexes (SCC) [M2{SCH2C6H4CH2S}]4(OTf)8. These complexes were characterized by NMR, mass, and UV-vis spectroscopies, cyclic voltammetry, as well as density functional theory studies and represent the first examples of SCCs constructed by thiolate groups and square-planar metal ions. The rectangular shape of tetranuclear complexes and square shape of octanuclear complex are confirmed by single-crystal structures and computational studies. The palladium complexes showed excellent catalytic activity in Suzuki C-C cross-coupling reactions with high turnover numbers (2 × 10(7)), even with low catalyst loading.
authors.affiliation: Chemistry Division, Bhabha Atomic Research Centre , Mumbai 400 085, India.
authors.forename: K V
authors.initials: KV
authors.lastname: Vivekananda
authors.affiliation: Chemistry Division, Bhabha Atomic Research Centre , Mumbai 400 085, India.
authors.forename: S
authors.initials: S
authors.lastname: Dey
authors.affiliation: Homi Bhabha National Institute, Training School Complex , Mumbai 400094, India.
authors.forename: D K
authors.initials: DK
authors.lastname: Maity
authors.affiliation: Department of Chemistry, Texas A&M University , P.O. Box 30012, College Station, Texas 77842-3012, United States.
authors.forename: N
authors.initials: N
authors.lastname: Bhuvanesh
authors.affiliation: Chemistry Division, Bhabha Atomic Research Centre , Mumbai 400 085, India.
authors.forename: V K
authors.initials: VK
authors.lastname: Jain