Mercury cyanamide

Mercury peroxide, 4601 Mercury(I) azide, 4607 Mercury(I) bromate, 0270 Mercury(I) chlorite, 4074 Mercury cyanamide, 0520 Mercury fluoride, 4306 Mercury hypophosphate, 4612 Mercury nitrate, 4604 Mercury oxide , 4608 Mercury thionitrosylate, 4605 Mercury ) 5-nitrotetrazolide, 0977 Mercury ) acetylide, 0971 Mercury ) ao-dinitromethanide, 0703 Mercury ) amide chloride, 3993 Mercury ) azide, 4599 Mercury ) bromate, 0269 Mercury ) bromide, 0268 Mercury ) chlorite, 4071... 

Following our nomenclature, HgNCN(I) stands for the mercury carbodiimide (Scheme 3.1) and HgNCN(II) represents the mercury cyanamide (Scheme 3.2). In fact, the two different compounds (or two different solid-state isomers, as... 

Fig. 3. 42 Structural motifs from the crystal structures of mercury carbodiimide (a) and mercury cyanamide (b).

The first question of any solid-state chemist thinking in terms of structure and energetics will definitely be What is the stable polymorph, mercury carbodiimide, HgNCN(I), or mercury cyanamide, HgNCN(ll) Unfortimately, it is impossible to answer this question by means of differential thermal analysis because both polymorphs decompose, prior to interconversion, at about 230 °C to yield a white polymer and mercury metal. Thus, theoretical reasoning and/or electronic-structure theory is needed. Let us attempt to argue using both classical and quantum-chemical means. 

Fig. 3.44 Structures of mercury cyanamide and carbodiimide oligomers (a) resembling the -Hg-NCN- chains in the extended structures of HgNCN(l)...

Finally, let us not forget that there is a single, simple frame of understanding which correctly, albeit qualitatively, predicts the energetic order of mercury carbodiimide and mercury cyanamide, and it is based on chemical ideas, namely Pearson s concept of hard and soft acids and bases soft prefers soft and hard prefers hard. The absolute softness of Hg + (7.7 eV, see Table 2.3) lies between those of Pb and Ag+ such that a cyanamide anion and not a carbodiimide anion will be the preferred bonding partner for Hg +, just as for Pb + and Ag+. I cannot refrain from noting that I find this quite remarkable. 

Mercury(ll) azide, 4604 Mercury 5,5 -azotetrazolide, 0980 Mercury bis(cbloroacetylide), 1356 Mercury(l) bromate, 0271 Mercury(ll) bromate, 0270 Mercury(ll) bromide, 0269 Mercuiy(I) cblorite, 4080 Mercury(II) cblorite, 4077 Mercury(I) cyanamide, 0523... 

N—C—O + C—C. The construction of the oxazole ring by the condensation of a-halogeno ketones with primary amides (equation 122) is the Bliimlein-Lewy synthesis (1884/1888). The method succeeds best when the resulting oxazole contains one or more aryl substituents. The use of formamide leads to oxazoles with a free 2-position and in this case it is possible that the reaction proceeds as in equation (113). 2-Aminooxazoles are produced by the action of a-halogeno ketones on urea and its derivatives (equation 123) or on cyanamide (80ZOR2185). The mercury(II) sulfate-catalyzed condensation of alkynic alcohols or their esters with primary amides leads to trisubstituted oxazoles (equation 124). 

Tetra (phenylmercuri) thiourea, (C6HgHg)4N3CS,—The above acetate treated with thiourea gives this derivative and ammonium acetate. It is insoluble in the usual solvents and darkens at 104° to 105° C.. When boiled with alcohol it decomposes, giving mercuric sulphide, mercury diphenyl, and phenylmercuri cyanamide,... 

ABSOLUTE ALCOHOL or ABSOLUTE ETHANOL (64-17-5) Forms explosive mixture with air (flash point 55°F/13°C). Reacts, possibly violently, with strong oxidizers, bases, acetic anhydride, acetyl bromide, acetyl chloride, aliphatic amines, bromine pentafluoride, calcium oxide, cesium oxide, chloryl perchlorate, disulfuryl difluoride, ethylene glycol methyl ether. Iodine heptafluoride, isocyanates, nitrosyl perchlorate, perchlorates, platinum, potassium- er -butoxide, potassium, potassium oxide, potassium peroxide, phosphonis(III) oxide, silver nitrate, silver oxide, sulfuric acid, oleum, sodium, sodium hydrazide, sodium peroxide, sulfmyl cyanamide, tetrachlorosilane, i-triazine-2,4,6-triol, triethoxydialuminum tribromide, triethylaluminum, uranium fluoride, xenon tetrafluoride. Mixture with mercury nitrate(II) forms explosive mercury fulminate. Forms explosive complexes with perchlorates, magnesium perchlorate (forms ethyl perchlorate), silver perchlorate. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

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