title: Synthesis of a labile sulfur-centred ligand, [S(H)C(PPh2S)2](-): structural diversity in lithium(i), zinc(ii) and nickel(ii) complexes.
abstract: A high-yield synthesis of [Li{S(H)C(PPh2S)2}]2 [Li2·(3)2] was developed and this reagent was used in metathesis with ZnCl2 and NiCl2 to produce homoleptic complexes 4 and 5b in 85 and 93% yields, respectively. The solid-state structure of the octahedral complex [Zn{S(H)C(PPh2S)2}2] (4) reveals notable inequivalence between the Zn-S(C) and Zn-S(P) contacts (2.274(1) Å vs. 2.842(1) and 2.884(1) Å, respectively). Two structural isomers of the homoleptic complex [Ni{S(H)C(PPh2S)2}2] were isolated after prolonged crystallization processes. The octahedral green Ni(ii) isomer 5a exhibits the two monoprotonated ligands bonded in a tridentate (S,S',S'') mode to the Ni(ii) centre with three distinctly different Ni-S bond lengths (2.3487(8), 2.4500(9) and 2.5953(10) Å). By contrast, in the red-brown square-planar complex 5b the two ligands are S,S'-chelated to Ni(ii) (d(Ni-S) = 2.165(2) and 2.195(2) Å) with one pendant PPh2S group. DFT calculations revealed that the energetic difference between singlet and triplet state octahedral and square-planar isomers of the Ni(ii) complex is essentially indistinguishable. Consistently, VT and (31)P CP/MAS NMR spectroscopic investigations indicated that a mixture of isomers exists in solution at room temperature, while the singlet state square-planar isomer 5b becomes favoured at -40 °C.
authors.affiliation: Department of Chemistry, University of Calgary, Calgary, AB T2N 1N4, Canada.
authors.forename: Ramalingam
authors.initials: R
authors.lastname: Thirumoorthi
authors.affiliation: Department of Chemistry, University of Calgary, Calgary, AB T2N 1N4, Canada.
authors.forename: Tristram
authors.initials: T
authors.lastname: Chivers
authors.affiliation: Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, FI-40014, Finland. jari.a.konu@jyu.fi.
authors.forename: Susanna
authors.initials: S
authors.lastname: Häggman
authors.affiliation: Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, FI-40014, Finland. jari.a.konu@jyu.fi.
authors.forename: Akseli
authors.initials: A
authors.lastname: Mansikkamäki
authors.affiliation: Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, FI-40014, Finland. jari.a.konu@jyu.fi.
authors.forename: Ian S
authors.initials: IS
authors.lastname: Morgan
authors.affiliation: Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, FI-40014, Finland. jari.a.konu@jyu.fi.
authors.forename: Heikki M
authors.initials: HM
authors.lastname: Tuononen
authors.affiliation: Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, FI-40014, Finland. jari.a.konu@jyu.fi.
authors.forename: Manu
authors.initials: M
authors.lastname: Lahtinen
authors.affiliation: Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, FI-40014, Finland. jari.a.konu@jyu.fi.
authors.forename: Jari
authors.initials: J
authors.lastname: Konu