Halides and pseudohalides

Boggess and D. A. Zatko, fnorg. Nuclear Chem. Letters, 1976, 12, 7. 

XeFg to produce XeFgjCoFj, an antiferromagnetic solid with the three-dimensional ordering temperature, Ti, = 140 2 

Slivnik, B. 2emva, M. Bohinc, D. Hanzel, J. Grannec, and P. Hagenmuller, J. Inorg. Nuclear Chem., 1976, 38, 997. 

Harkema and W. Van der Craaf, Inorg. Nuclear Chem. Letters, 1975,11, 813. 

Misumi et al. 61 have measured the formation constant of [Co(NCS)4]2 , log fi2 = 15.5. The electronic and i.r. spectra and magnetic moments of the novel [CoX2Y2]2 and [CoX3Y]2- [X = NCS or NCO, Y = N(CN)2] are consistent with a pseudo-tetrahedral structure.62 Miezis63 has examined the frequency and intensity of v(CN) 

Goedken and S.-M. Peng, paper given at 16th International Coordination Chemistry Conference, 

Misumi, M. Aihara, and S. Kinoshita, Bull. Soc. Chem. Japan, 1974, 47,127. 

When COCI2 in acetonitrile was treated with R NCN, the presence of [(MeCN)2Co(CN)2], [(MeCN)Co(CN)3]-, and Co(CN) - was demonstrated by a range of physical measurements. The relative concentrations of these three species depend on the Co rCN concentrations. (R4N)3 [Co(CN)j] (R = Et or Bu ) were isolated and these react with oxygen to form (R4N)3-[Co(CN)502],1.5H20. Other workers have reported on the oxidation-reduction properties of [(CN)5Co—O2—CofCNlj] , formed by a redox 

Furuhashi, S. Komatsu, and A. Ouchi, Bull. Chem. Soc. Japan, 1972,45, 2942. 

Diazonium salts are the most reactive source of arylpalladium species and the reaction can be carried out at room temperature using Pd2(dba)3 as a catalyst in the absence of both phosphine ligand and base [44]. The reaction of diazonium salts means indirect substitution reaction of an amino group of anilines or aromatic nitro group with an alkene. The use of diazonium salts is synthetically more convenient than the use of aryl halides, because many aryl halides, particularly iodides, are prepared from diazonium salts. 

HR of electron-rich aryl bromides with 1,1- or 1,2-disubstituted alkenes such as methyl methacrylate (71) and crotonate (72) proceeds at room temperature in dioxane with the same catalyst to provide 73 and 74 [26]. 

Unlike aryl chlorides, unactivated alkenyl chlorides react more smoothly. It is generally recognized that alkenyl chlorides are much more reactive than aryl chlorides. However, curiously somewhat higher reactivity of chlorobenzene than the alkenyl chloride 75 was observed by the use of this catalyst in the following competitive reaction. The yield of 76 was higher than that of 77. 

Littke and Fu reported an interesting and important suggestion that commercially available Pd[P(f-Bu)3]2 is a resting state of the system in the HR, and not a catalytically active species. Change of the ratio of Pd to phosphine from 1 1 to 1 2 leads to a marked decrease in the rate of reactions, and the Pd monophosphine adduct PdP(f-Bu)3 is the active catalyst. The combination of Pd[P(t-Bu)3]2 and a phosphine-free Pd complex generates in situ the active 1 1 adduct [7]. 

Also diadamantyl(f-butyl)phosphine (1-20) is a good ligand for HR of aryl bromides at room temperature [51]. 

3H2O FeClj FeOCl. ° The reaction of BBr with anhydrous FeClj or anhydrous oxides of Fe gives anhydrous FeBrj. The structure of (4-EtpyH)[FeBr ] has been reported, the anion being tetrahedral.  

Reduction of p-oxo-bis[tetraphenylporphin iron(iii)] with sodium amalgam gives several products sequentially. The first reduction product is the radical-anion [(tpp)Fe ] , which has a spin state of - at 77 K and at 300 K. This is the first reported study of an Fe -porphyrin.Mossbauer data on a range of tetra-aryl-substituted iron-porphines and their p-oxo-bridged derivatives have been reported. A crystallographic study on bis(imidazole) otPy -tetraphenylporphinatoiron(iii) chloride-methanol solvate shows the [FeN ] core to be quasitetragonal. An n.m.r. study has been made of the related 

Plotnikov. A. A. Krasil nikova, N. M. El khones, and A. 1. Stepanov, Russ.J. Inorg. Chem., 

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Table 12.4 Some phosphoryl and thiophosphoryl halides and pseudohalides...

Reactions of a variety of weaker nucleophiles such as halide and pseudohalide ions and [Pt(PPh3)2(CNCH3)2] have been studied (747) and, as might be expected, ligand replacement is usually observed [Eq. (11)]. 

Packings of spheres having occupied tetrahedral and octahedral interstices usually occur if atoms of two different elements are present, one of which prefers tetrahedral coordination, and the other octahedral coordination. This is a common feature among silicates (cf. Section 16.7). Another important structure type of this kind is the spinel type. Spinel is the mineral MgAl204, and generally spinels have the composition AM2X4. Most of them are oxides in addition, there exist sulfides, selenides, halides and pseudohalides. 

In Table 6 the differences of free enthalpies of solvation for several anion ligands in a donor solvent D and in AN are given. HMPA shows very weak solvation whereas water is a very strong solvating agent for anions. The free enthalpies of solvation of halide and pseudohalide ions are by 4 to 15 keal/mol more negative than in aprotic donor solvents. 

The validity of reaction Scheme 1 is not limited to heterolyses of covalent bonds to carbon. It covers also cases where both X and Y are hetero-atoms (e.g. oxidation of halides and pseudohalides by OH, cf. Ref [40] or where X is a hetero atom and Y is a metal (cf. Ref [41])... 

Cationic indium(III) complexes could not be prepared with pyridine, but species such as [In(bipy)3]3+ and [In(phen)3]3+ are known as the perchlorate62 or nitrate64 salts, and [In(terpy)2](C104)3 has also been reported.67 Stability constants have been measured in the In3+/bipy and In3+/phen systems71,72 and for some substituted pyridines.9 The adducts of indium(III) halides and pseudohalides with pyridine and substituted pyridines have been... 

As with indium, the literature contains a number of surveys of the general inorganic1 and organometallic chemistry of thallium,273 and the reviews of this element already cited are also concerned with the adducts of the halides and pseudohalides,5 and with other aspects of the coordination chemistry.6 A monograph by Lee provides a most useful treatment of the literature up to 1970.274 The application of thallium compounds in organic synthesis has been discussed.275 276... 

When nickel(II) salts containing a coordinating anion (halide and pseudohalide) are reacted with NaBH4 in the presence of np3, trigonal bipyramidal nickel(I) complexes of the type [NiXnp3], in which the coordinating anion occupies die axial position, 39,340 are obtained. When nickel(II) salts with poorly coordinating anions are used, non-stoichiometric hydrido complexes of nickel(II) are obtained (equations 108 and 109). 

Among these, halide and pseudohalide complexes of the general formula AgP X (where X = halide or pseudohalide, P = phosphine and n = 1-4) have been studied in detail. 

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