Cyanogen, structure

B. H. Torrie and B. M. Powell, / Phys. Condensed Matter, 1,5827 (1989). Cyanogen Structure, Dynamics, and Intermolecular Potentials. 

A particularly interesting example of this method of synthesis is the cy-clrzation of the 4-amino-3-(2-aminophyenyl)-l,2,4-triazoloes 73 with cyanogen bromide. Primarily, this reaction was applied to synthesize the 6-amino-l,2,4-triazolo[4,3-d]benzodiazepine hydrobromides 74 the obtained products, however, were found to be the l,5-diamino-l,2,4-triazolo-[l,5-c]quinazolin-ium bromides 77. Structure elucidation of 77 was accomplished by direct... 

The proposed structure of 97 isolated from broiled sardines was confirmed by straightforward synthesis starting from5,6-diaminoquinolines. After reaction with cyanogen bromide it afforded the 2-amino-imidazo[4,5-/]quinolines 99 (R = H, Me), which was then converted into its 3-A-methyl derivative 100 by... 

Naturally occurring compounds called cyanogenic glycosides, such as lotau-stralin, release hydrogen cyanide, HCN, when treated with aqueous acid. The reaction occurs by hydrolysis of the acetal linkage to form a cyanohydrin, which then expels HCN and gives a carbonyl compound-fa) Show the mechanism of the acetal hydrolysis and the structure of the cyanohydrin that results. 

Preparation. A compd C2F6N2 was reported in 1936 among the prods of the action of F on Ag cyanide (Ref 2), but the structure was not proved until 1940, when it was prepd in good yield by the action of 1 pentafluoride on I cyanide (Ref 4). Since then it has been prepd as the major prod from the action of Ag di-fluoride on cyanogen chloride (Refs 6 10) by the interaction of Cl, Na fluoride, and cyanogen chloride in a sealed tube at 50° for 1 hour (Refs 9 10) and in low yields by the fluori-nation of ethylene diamine or ethyleneimine (Ref 7)... 

When cyanogen bromide was used instead of CS2, the corresponding guanidines 169 were obtained under analogous conditions [108]. Moreover, differently substituted guanidines 171 could be obtained in very good yields when the isothiourea 168 was alkylated with Mel under microwave irradiation and the product treated with a primary amine. An intramolecular version of this reaction was also described for the preparation of structure 172 present in several important natural products (Scheme 61). 

The structure of poly(iminocarbonates) synthesized by the direct interfacial polymerization of BPA and cyanogen bromide was analyzed by NMR, Fourier transform infrared spectroscopy and elemental analysis and found to be identical in all aspects to authentic poly(imino-carbonates) obtained by solution polymerization (46). 

A number of amidines have anthelmintic activity. Bunamidine (25), indicated for treatment of human pinworm infestations, is prepared from a-naphthylhexyl-ether (23) by Friedel-Crafts type reaction with cyanogen bromide and aluminum chloride to give nitrile (24). This, then, is reacted with the magnesium bromide salt of di-n-propylamine leading to the naph-thamidine structure (25). -... 

The imidazole ring system provides the nucleus for two diuretic agents with structures unusual for that activity. Reaction of the N-cyanoaniline 140 (obtainable from the aniline (139) and cyanogen bromide) with N-methylchloroacetamide leads to the heterocycle 142. The sequence can be rationalized by... 

Lauble, H., Miehlich, B., Forster, S. et al. (2002) Crystal structure of hydroxynitrile lyase from Sorghum bicolor in complex with the inhibitor benzoic acid a novel cyanogenic enzyme. Biochemistry, 41, 12043-12050. 

Cyanogen bromide can be used to activate hydroxyl groups on particles to create reactive cyanate esters, which then can be coupled to amine-containing ligands to form an isourea bond (Figure 14.17). CNBr activation also can produce cyclic imidocarbonate groups, which are less reactive than the cyanate ester, but can form imidocarbonate bonds. The exact reactive species formed by the reaction is dependent on the structure of the hydroxylic support being activated (Kohn and Wilchek, 1982). 

Draw the structure of cyanogen azide. Speculate on the stability of this molecule. 

It can also be prepared from carbon and nitrogen by electric discharge between carbon electrodes in a nitrogen atmosphere. Numerous derivatives of cyanogens are known, including cyanogen halides, XCN. These compounds form trimers known as the cyanuric halides, which have the cyclic structure... 

The structures of two formal trimers of cyanogen iV-oxide of the composition CfNAT were established by X-ray crystal structure analysis. In the crystals, the two rings are almost but not quite coplanar, with dihedral angles of 4.56(0.59)° in the case of structure 4 and 9.43(0.17)° in the case of structure 5 <2000J(P2)473>. 

An unexpected formation of a biguanide occurred 754) in the reaction of trans-l-amino-2-hydroxycyclohexane (LI) with cyanogen bromide in the presence of sodium acetate. In addition to the expected trans-2-amino-3a,4,5,6,7,7a-hexahydro-benzoxazole (LII), traces of its trimer having the biguanide structure (LIII) were obtained. 

Hirshfeld and Mirsky (1979) evaluated the relative contributions to the lattice energy for the crystal structures of acetylene, carbon dioxide, and cyanogen, using theoretical charge distributions. Local charge, dipole and quadrupole moments are used in the evaluation of the electrostatic interactions. When the unit cell dimensions are allowed to vary, inclusion of the electrostatic forces causes an appreciable contraction of the cell. In this study, the contributions of the electrostatic and van der Waals interactions to the lattice energy are found to be of comparable magnitude. 

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