Formamide complexes

Table 5.16. A comparison ofH-bond energy (AAhb) andNRTbond orders ( ab) for C=0- H—N hydrogen bonds in binary formamide complexes...

HgSe was first deposited from an iodide-complexed solution using se-lenosemicarbazide. Two other depositions were described, both using selenosulphate. One used an alkaline Hg-formamide complex. The as-deposited films did not show an XRD pattern, suggesting that the material was either amorphous or... 

In the other two studies, selenosulphate was used. In one, a formamide complex of Hg, made by dissolving HgO in formamide, was used [154]. The solution was made ca. 0.5 M in NaOH, and a trace of polyvinyl pyroUidone was added. The deposition was carried out at room temperature. The polyvinyl pyrollidone slowed the deposition somewhat and apparently improved fihn uniformity and adherence as well as slightly increased terminal thickness (500 mn). It was noted that films were not obtained with the usual complexants, such as ammonia, triethanolamine, and cyanide. It is not mentioned in which way these complexants were unsuitable ammonia and triethanolamine might be too weak, resulting in immediate precipitation in solution. Also, addition of ammonia to some mercuric salts tends to lead to precipitation of insoluble products. Cyanide, however, is a very strong com-plexant and would be expected to control such bulk precipitation better than formamide. Iodide, a strong complex for Hg (and successfully used to deposit HgS, as described earlier), resulted in film deposition but with poor reproducibility. 

C. and 74.5 mL. of a 0.67 molar solution of sulfur trioxide-dimethyl-formamide complex in dimethylformamide are added. The mixture is stirred thoroughly and is allowed to stand for about five minutes to assure the complete formation of the mixed anhydride of lysergic and sulfuric acids. To the solution are then added... 

Coupling of the lithium salts of allylic sulfones 9 by oxidation with iron(II) chloride dimethyl-formamide complex and Cope rearrangement of the 1,6-disulfones affords vicinal sulfones exclusively with threo configuration. In the case of 9c, a mixture of geometrical isomers of lie is obtained999. 

Now cool the formamide solution, and when it has cooled to 5 °C, add 100 ml of IM SOj-formamide complex. Allow 10 minutes of stirring in the cold before then adding 25 ml of diethylamine. 

J.E. Del Bene, 1. Alkorta, J. Elguero, Ab initio EOM-CCSD spin —spin couphng constants for hydrogen-bonded formamide complexes bridging complexes with H3,(NH3)2, H20,(H20)2, FH, and (FH)2, J. Phys. Chem. A 112 (2008) 6338-6343. 

With respect to interpreting these results in terms of a dipole alignment model, it would appear unwise to do this, at least relative to the current studies. The actual values of the contributions of various terms are given in the text. In particular, for the case of a single H2O...formamide complex, the dipole term is not the only major contributor, and significant contributions were usually observed... 

C2H6CdCl2N20, Methylurea cadmium chloride complex, 22, 640 C2HgCdCl2N2O2, Cadmium chloride-formamide complex, 32B, 445 C2H6CI2CUN2O, Dimethylnitrosamine copper(II) chloride, 34B, 573 C2H6CI2CUOS, Dichloro(dimethylsulfoxide)copper(II), 45B, 1211 C2H6CI2CUO2 0.5 H2O, Dichloro-(1,2-ethanediol)copper(II) hemihyd-rate, 42B, 877... 

Also, Os3(H)2(CO)9(PMe2Ph) reacts with p-tolyl isocyanate to give a bridged carbamate complex . When Os3(H)2(CO)io is used, formamide complexes and other products resulting from fragmentation reactions are obtained. For example, p-tolyl isocyanate reacts with the osmium hydride complex and ruthenium complexes to form formamido, ureylene... 

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