Nickel complexes structural chemistry

The structural chemistry of some metal dithiocarbamates, i.e. systematics, coordination modes, crystal packing, and supramolecular self-assembly patterns of nickel, zinc, cadmium, mercury,363 organotin,364 and tellurium,365 366 complexes has been thoroughly analyzed and discussed in detail. Supramolecular self-assembly frequently occurs in non-transition heavier soft metal dithiocarbamates. Thus, lead(II),367 bismuth(III)368 zinc,369 cadmium,370 and (organo)mercury371 dithiocarbamates are associated through M- S secondary bonds, to form either dimeric supermolecules or chain-like supramolecular arrays. The arsenic(III)372 and antimony(III)373 dithiocarbamates are... 

In summary, it can be seen that the structural chemistry of the zero-valent complexes has to date been dominated by investigations on nickel carbonyl. Preliminary studies on other compounds indicate that the tetrahedral structure may not be the only possibility, and thorough investigation of the unsaturatcd species is likely to develop. Back-donation may be examined by study of force constants, in favorable cases merely of observed frequencies, and it would be interesting to see more cases of competition for back-donation, as in (MeNC)3Ni(CO). 

Transition metal hydroxyoxime complexes have been reviewed very recently.2507 Their use in both analytical chemistry and extraction metallurgy is well known. The square planar structure of the bis chelate complex NiL (347) with the deprotonated 2-hydroxybenzaldoxime (HL) is typical of this series of nickel complexes.2508 Their bis adducts, NiLJ, with bases such as py, substituted pyridines and cyclomethyleneimines, are six-coordinate.2509 The acyl oxime (H2L) complexes are similar to the aforementioned complexes being either square planar bis chelates Ni(HL)2 (348) or octahedral bis adducts, Ni(HL)2B2.2507 When the acyl oxime acts as a dibasic ligand L, the corresponding (NiL) complexes are insoluble and involve extensive polymerization. 

Group 4, surface chemistry on oxides, 12, 515 Group 5, surface chemistry on oxides, 12, 524 molybdenum, surface chemistry on oxides, 12, 529 into nickel complexes, 8, 59-60 with palladium, GO insertion, 8, 200 tungsten, surface chemistry on oxides, 12, 531 on zinc compounds, 2, 366 Alkoxido-imido tungsten complexes structure and properties, 5, 754—755 synthesis, 5, 750/... 

The coordination chemistry of the hexaphyrin system has provided a number of surprises [190]. The addition of nickel chloride to the isomeric mixture of hexaphyrins 250 leads to a single product. The proposed structure of the resulting nickel complex is shown as compound 254 in Scheme 44. Other metals were also found to react with this and other isomeric mixtures of hexaphyrins to give rise to only one isomeric product. For instance, treatment of either 250 or 252 with zinc chloride gives the bimetallic complexes 255 or 256 as one isomer, respectively (Scheme 45). In contrast, the reaction of 253 under identical conditions gives rise to a similar complex 257, wherein, the positions of the ter substituents are different from those reen in the previous examples (Scheme 46). The reactions of hexaphyrins with zinc would appear to indicate that the two isomers normally... 

This contribution provides an overview of contemporary synthetic methods of broad applicability that involve the preparation and use of nickel jt-complexes as starting materials or reactive intermediates. Numerous excellent reviews on the chemistry of nickel have appeared that are complementary to this contribution in subject and scope. An outstanding review by Chetcuti describes the knovm jt-complexes of nickel,I l and several other structural classes of nickel complexes have been reviewed " o-bonded organo-nickel compounds are reviewed in Houben-Weyl, Vol. 13/9b, pp 632-700. The historical development and early applications of nickel chemistry have been reviewed byWilkePl and Jolly,I ] industrial applications have been reviewed by Keim,Pl and several other reviews on specific groups of synthetic transformations have appeared. The organometallic... 

O Keeffe M (1977) On the arrangements of ions in crystals. Acta Cryst A33 924-927 Melnik M, Sramko T, Dunaj-Jurco M et al (1994) Crystal structures of nickel complexes. Reviews of inorganic chemistry. Rev Inorg Chim 14 1-346... 

Reaction of [NiCPRsKti rri -1,6-diene)] (R = Me, Ph) complexes with 1,6-heptadiyne afforded 1 the bis-alkyne nickel complexes [Ni(PR3)(T 2 Ti2. 6.( . H8)], structurally characterised for R = Me. The synthesis, reaction chemistry and X-ray crystal structure of bis(tetramethylbutynediol)nickel(0), [Ni(Ti2-H0CMe2CCCMe20H)2l, which represents the first homoleptic monoalkyne complex of nickel has been reported. ... 

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