Cyanides, Isocyanides and Related Complexes

4 Cyanides, Isocyanides and Related Complexes. - IR and Raman data were used in a quantitative study of coordination of Mg + (as Mg(C104)2) by CD3CN. A comparison of the vCN(free)/vCN(complex) ratio shows that the primary coordination number of Mg + by CD3CN is 

The resonance Raman spectrum of [Mo2( CN)8] shows VsCN at 2070 cm compared to 2113 cm in the CN analogue. Electrochemically generated [(NC)7Mo -CN-PF(L)4-NC-Mo (CN)7] where L = NH3 or i(en), show IR vCN bands consistent with the valence-trapped Mo Mo sites.  

IR bands due to vCN were used to determine the geometry in cis/trans isomers of (p-R-C6H4NC)2W(dppe)2, where R = NO2, CN, F, CF3 or CH3. The replacement of aryl H by CH3 led to the formation of only trans complexes.  

The complexes Cl2Sn-(NC)MnL c5 where = cis- or trans-(OC)2[P(R)3] (dppm), R = Ph or OEt, all have vCN at higher wavenumbers than in the mononuclear manganese precursors. This shows that the Sn CE fragment is a 

The complex (46) has vCN bands at 2166 cm (Pt-bound) and 2149 cm (Fe-bound), showing the lower 7i-back-bonding ability of the platinum fragment. Characteristic vCN values were obtained for the cyano-bridged species trans-Cp(dppe)Fe-CN-M(hfa)2-NC-Fe(dppe)Cp, where M = Mn, Fe, Co, Ni, Cu, Zn or Cd, hfa = hexafluoroacetylacetone, i.e. 2073-2146 cm , compared to Cp(dppe)Fe(CN) (2062 cm 

4 Cyanides, Isocyanides and Related Complexes - IR spectra of MNC (where M = Mg, Ca, Sr or Ba) in low-temperature matrices show that vCN decreases and the band becomes broader as M increases in mass. This is ascribed to a decreasingly rigid linear geometry. 

The CN stretching mode is seen as a single band in the range 2110-2145 cm for [M (N)(CN)5]3- and [MV(N)(CN)4] -, where M = Cr or Mn. o The complexes LWX(MeCN)-(CO), where X = C1, Br or I L = hydrotris(3,5-dimethylpyrazol-l-yl)borate, give a vCN band near 1700 cm due to the four-electron donor C-nitrile ligand. The value is close to the range for a C=N double bond.  

Values of vCN modes were reported for [py(OEP)Fe-CN-Cu(Npy3)] , and related complexes, where Npy3 = tris(2-pyridylmethyl)amine. These were used to suggest the nature of bridge bonding in these complexes and their reduced analogues. Compound (56), where Fp = Fe(CO)2Cp, gives i.r bands due to vCN of CNMe at 2206 cm and of CNFp at 2149 cm 1.279 

The resonance Raman spectra (vCN) of (NC)5Fe(CN)Ru(NH3)5 in a range of solvents gave evidence for significant solvent effects on the vibronic coupling.2 4 (CN in the bridging complex (58) is at 2158 cm i, 40 cm i higher than in the parent CpFe(CO)2CN.2  

Isomerisation of trans,mer-lrC 2 CN) PEt2Ph)2 to the fac- and c/X r-isomers was followed using vCN bands in the IR spectrum.2  

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Seven and eight coordinate molybdenum complexes and related molybaenum(IV) oxo complexes with cyanide and isocyanide ligands. S. J. Lippard, Prog. Inorg. Chem., 1976, 21, 91-103 (44). 

Lippard, Stephen J., Seven and Eight Coordinate Molybdenum Complexes and Related Molybdenum (IV) Oxo Complexes, with Cyanide and Isocyanide... 

Cyanides.—A concise review of the seven- and eight-co-ordinate molybdenum complexes and related molybdenum(vi) 0x0 complexes, with cyanide and isocyanide ligands has appeared and Group Via cyanide complexes have been reviewed within the broader scope of transition metal cyanides. ... 

The computation of rotational constants Be from the inertia moments I corresponding to the interatomic distances in both types of comple.xes illustrates the situation clearly the cyanide and isocyanide isomers have rotational constants separated by about 0.6 GHz, and this shift upwards for the isocyanide species may be useful for their spectroscopic investigation, as already done for the pair of isomers MgNC and MgCN. Corresponding dipole moments are indicated in this connection. It should be added that the present values are consistent with the experimental parameter B = 4.358596 GHz assigned to a related complex FeCO [34]. 

Reaction of Fe(CO)s with dialkyl sulfides in the presence of trimethylamine-A -oxide leads to simple, mono-substituted Fe(CO)4(SR2) complexes (Scheme 71), whereas this reaction performed with cyclic thioethers gave dinuclear complexes. Dinuclear complexes related to 51 with a variety of groups bridging between the two sulfur atoms have been derivatized with cyanide and organic isocyanides. 

Iron carbonyl complexes with cyanide or organic isocyanide ligands have been presented in Section 6.01.4.1. The chemistry of those compounds is related to the preparation of compounds which contain both cyanide and S-donor ligands. Reaction of FeCl2 with [Et4N]CN or organic isocyanides in the presence of CO and thiolate ligands is a convenient entryway into this class of compounds (Scheme 75). ... 

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