New nickel complexes with an S4 coordination sphere; synthesis, characterization and reactivity towards nickel and iron compounds

Abstract

Three new nickel complexes have been synthesized with the ligands Hbss (4-mercapto-2-thia-1-butylbenzene) and Hbsms (2-(benzylsulfanyl)-2-methyl-1-propanethiol

A molecular cage of nickel(ii) and copper(i): a [{Ni(L)2}2(CuI)6] cluster resembling the active site of nickel-containing enzymes

“…The focus of our attention is to study the chemistry involving the synthesis and reactivity of nickel thiolate complexes in relation with the structure and function of protein active sites, as described above. 1,3,[5][6][7][8] Herein, we report the synthesis of a new bidentate S 2 thioether-thiolate ligand (L),w the mononuclear low-spin nickel complex (1)w and the hetero-octanuclear nickel(II) copper(I) cluster complex [{Ni(L) 2 } 2 (CuI) 6 ] (2),z which contains two NiS 4 units, four trigonal-planar CuI 2 S and two tetrahedral CuI 2 S 2 sites.The reaction of Ni(acac) 2 with two equivalents of the thiouronium chloride salt of the ligand, in the presence of two equivalents of tetramethylammonium hydroxide, led to an immediate color change to deep brown and the new low-spin square-planar complex [Ni(L) 2 ] (1) was isolated as flocculent reddish-brown crystals in high yield (Scheme 1). Equimolar solutions of Ni(L) 2 (1) in dichloromethane and copper(I) iodide in acetonitrile were mixed under argon and stirred for an hour to yield a dark brown precipitate.…”

“…The focus of our attention is to study the chemistry involving the synthesis and reactivity of nickel thiolate complexes in relation with the structure and function of protein active sites, as described above. 1,3,[5][6][7][8] Herein, we report the synthesis of a new bidentate S 2 thioether-thiolate ligand (L),w the mononuclear low-spin nickel complex (1)w and the hetero-octanuclear nickel(II) copper(I) cluster complex [{Ni(L) 2 } 2 (CuI) 6 ] (2),z which contains two NiS 4 units, four trigonal-planar CuI 2 S and two tetrahedral CuI 2 S 2 sites.…”

“…3 and 4). To the best of our knowledge, [{Ni(L) 2 } 2 (CuI) 6 ] is the first compound with a NiS 4 coordination displaying the aforesaid nickel to proton anagostic interactions.…”

Nickel Thiolate Complexes as Ligands for Copper and Zinc: Novel Additions to a Library of Binding Modes

“…(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) discrete NiCu or NiNi dinuclear complexes [4,5,8,11] or linear trinuclear Ni 3 or Ni 2 Cu complexes; [8,15] or they may bind to four different metal ions through µ 3 -S bridges in larger Ni 2 Cu 4 aggregates. [16] The nuclearity of the cluster and type of aggregate that is formed is largely dependent on the stoichiometry of the reactants and the presence or absence of coordinating anions.…”

“…[17][18][19] Recently, we have reported the mononuclear complexes [Ni(bsms) 2 ] and [Ni(xbsms)] in which the nickel ion is in an S 4 coordination environment [H 2 xbsms = α,αЈ-bis(4-mercapto-3,3-dimethyl-2-thiabutyl)-o-xylene; Hbsms = 4-mercapto-3,3-dimethyl-1-phenyl-2-thiabutane]. [26] The reactivity of these mononuclear complexes towards nickel and iron has been studied and the trinuclear nickel complexes [Ni 3 [15,27] The reactivity of these complexes towards copper(I) and zinc(II) salts has now been investigated, resulting in a number of novel aggregates with unprecedented structures that are described below.…”