Chlorine atom-solute complexes

The pulse radiolysis of carbon tetrachloride and solutions of carbon tetrachloride shows that transient species are produced with absorption spectra from 3000 to 7000 A. (3). These species have been assigned to chlorine atom-solute charge transfer complexes (4). No assignment was made to positive ions as in the glassy state. 

Concentration of an ethanolic solution of dimethylglyoxime, cobalt(n) chloride and benzotriazole results in deposition of crystalline complex 68. The product is stable at room temperature however, it slowly decomposes upon heating. Thermal analysis reveals that the compound releases first the chlorine atom and 50% of the benzotriazole content to form a new complex that is stable to 225 °C. Probably in this new form, the benzotriazole moiety coordinates two cobalt ions simultaneously. Further heating to 350 °C removes the benzotriazolyl moieties completely <2003JPY699>. The first step of decomposition can be summarized as follows ... 

Chlorination of natural rubber (NR) is carried out with chlorine in carbon tetrachloride solution at 60-90°C to yield a chlorinated rubber containing about 65% chlorine, which corresponds to 3.5 chlorine atoms per repeat unit. The process is complex and includes chlorine addition to the double bond, substitution at allylic positions, and cyclization. Chlorinated rubber has high moisture resistance and is resistant to most aqueous reagents (including mineral acids and bases). It is used in chemical- and corrosion-resistant paints, printing inks, and textile coatings. Bromination of butyl rubber is also practiced [Parent et al., 2002]. 

Bunce, N. J., K. U. Ingold, J. P. Landers, J. Lusztyk, and J. C. Scaiano, Kinetic Study of the Photochlorination of 2,3-Dimethyl-butane and Other Alkanes in Solution in the Presence of Benzene. First Measurements of the Absolute Rate Constants for Hydrogen Abstraction by the Free Chlorine Atom and the Chlorine Atom-Benzene tr -Complex. Identification of These Two Species as the Only Hydrogen Abstractors in These Systems, . /. Am. Chem. Soc., 107, 5464-5472 (1985). 

In this way the dissociable chlorine atoms are represented united directly to cobalt, and hence there is no difference between these chlorine atoms and chlorine atoms in cobaltous chloride. The chlorine atom not dissociable is included in the centre shell round the cobalt atom. This shell around the metal is compared to the water molecules associated with some metallic ions which retard their mobility, the complex moving as a whole through a solution. These associated molecules, it is suggested, take the form of shells of water around the atom, the molecules being linked together by oxygen atoms. In the ease of trichloro-triammino-cobalt all the chlorine atoms arc within the shell and the substance is a non-electrolyte. Three different formula are possible, none of which will ionise in solution, viz. ... 

The oxalate, [Cr(NH3)4H20.Cl]C204, separates in violet-red crystals on the addition of potassium oxalate to a solution of the chloride. It is sparingly soluble in water, and the solution gives a precipitate of calcium oxalate with calcium chloride. A freshly prepared solution of the salt in nitric acid gives no precipitate with silver nitrate. The chlorine atom in the chloro-aquo-salts is within the complex, and hence silver chloride is not at first precipitated by silver nitrate on boiling with nitric acid and silver nitrate, however, chlorine is precipitated as silver chloride. 

Dichloro - tetrammino - iridic Chloride, [Ir(NH3)4Cl2]Cl2, is formed when excess of concentrated hydrochloric acid is added to a solution of the nitrate. It crystallises from boiling water in violet octahedra. Only half of the chlorine in the compound is precipitated by silver nitrate, thus indicating that two chlorine atoms are within the complex. 

Reaction Scheme of CMS Resists. The transient absorption spectrum shown in Figure 6 and observed for irradiated CMS films is mainly composed of two components as based on pulse radiolysis data of solid films of CMS and polystyrene, and CMS and polystyrene solutions in cyclohexane, chloroform, and carbon tetrachloride. An absorption with a maxima at 320 nm and 500 nm as due to the charge transfer radical-complex of the phenyl ring of CMS and chlorine atom (see Figure 14) and an absorption with maxima at 312 and 324 nm is due to benzyl type radicals (see Figure 11). 

The selectivity of chlorination reactions carried on in solution is increased markedly in the presence of benzene or alkyl-substituted benzenes because benzene and other arenes form loose complexes with chlorine atoms. This substantially cuts down chlorine-atom reactivity, thereby making the chlorine atoms behave more like bromine atoms. 

From solutions of GaCl2 in hot 1,3,5-trimethylbenzene the colorless crystalline bis(arene) complex [C6H3(CH3)3]2Ga+ GaCl4 (XLVI) has been isolated (158). The structural study reveals a bent sandwich structure for the cationic moiety, as indicated schematically in Fig. 9. The tetrachlorogallate tetrahedra are once more only weakly coordinated, this time via one chlorine atom each to the Ga(I) centers of two bis(arene)gallium units, forming a chainlike coordination polymer. The steric requirement of the mesityl ligands is... 

As mechanistic hypothesis it was proposed (9-11) that the excited platinum complex undergoes homolytic Pt Cl cleavage affording a Ptm intermediate and an adsorbed chlorine atom (Scheme 1), by analogy with the known photochemistry of hexachloroplatinate in homogeneous solution (23,31). Electron injection from the platinum(III) complex into the titania conduction band reforms PtIv. Thus, the... 

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