System carbon tetrachloride

The third paper in this group106 is concerned with the isolated triphenylphosphine-carbon tetrachloride system, and the authors show how these compounds react only in the presence of small amounts of polar impurities, to produce initially the salt... 

Depending on the reaction conditions, halogenation of thieno[2,3-Z>]pyridine (20) can lead to a variety of products resulting from substitution, addition, and oxidation reactions. 2,3-Dibromo-thieno[2,3-/)]pyridine is produced by the reaction of compound (20) with bromine in an aqueous carbon tetrachloride system and the 2,3-dichloro-2,3-dihydro derivative is formed from the same starting material upon treatment with chlorine in chloroform/water or with iodobenzene dichloride in aqueous acetonitrile (70JHC81, 71JHC931). 

Similarly for the ethanol + carbon tetrachloride system considered above, at 65-08 °C,... 

Nucleophilic Attack at Halogen. The reactions occurring in the triphenylphosphine-carbon tetrachloride system continue to attract attention. The salt (67), which is the first isolable product from the reactions of the above system, undergoes ready dechlorination on treatment with trisdimethylaminophosphine (TDAP) to form the ylide (68) and the dichlorophosphorane (69). This reaction offers a convenient route to the ylide (68), and enables the course of other reactions occurring in the triphenyl-... 

Deoxygenation of phosphine oxides can be achieved by the sequence outlined in Scheme 10. Although the reaction mechanism was not established, it seems not unreasonable to suggest that the phosphorane (108) is an intermediate. Details of further applications of the triphenylphosphine-carbon tetrachloride system to... 

Figure 10.2-1 (a) Equilibrium-total pressure versus composition for the ethyl iodine-carbon tetrachloride system at T = 49.99°C. b) Equilibrium total pressure versus composition for the carbon disulfide-acetone system at 7 = 35.17°C. (c) Equilibrium total pressure versus composition for the chloroform-acetone system at 7 = 35.17°C. (d) The x-y diagram for the chloroform-acetone systerp at 7 = 35.17°C. 

Nucleophilic Attack at Halogen. Further studies have been reported of the reactions of diols with the triphenylphosphine-carbon tetrachloride reagent. It has now been applied to 1,2-diols (in the presence of potassium carbonate) to form epoxides and to the trans-6 o (84), the nature of the product depending on the relative amounts of phosphine and diol present. The major product of reactions involving equimolar quantities of phosphine and diol is (85). The cyclodehydration product (86) is formed in only poor yield. In the presence of carboxylic acids, the triphenylphosphine-carbon tetrachloride system causes ring-opening of epoxides with the formation of c -enol esters, the reaction presumably proceeding via nucleophilic attack by the oxirane at an acyloxyphos-phonium intermediate. ... 

VISCOSITY ACTIVATION ENERGY OF THE N-HEPTANOL-CARBON TETRACHLORIDE SYSTEM. 

Dacre, B. Benson, G. C. Application of quasi-lattice theory to alcohol - carbon tetrachloride systems Can. J. Chem. 1963,41... 

K. F. Denning and J. A. Plambeck, Can. J. Chem., 60, 1600 (1972). Conductance and viscosity of the tetrabutylammonium bromide-carbon tetrachloride system. 

Vijayaraghavan, S. V. Deshpande, P. K. Kuloor, N. R. Isobaric vapour-liquid equilibrium studies od di (iso) propyl ether - carbon tetrachloride system. J. Indian Inst. Sci. 1965, 47, 139-141. 

Fowler, R. T. Norris, G. S. Azeotropism in binary solutions the ethyl methyl ketone - carbon tetrachloride system. J. Appl. Chem. 1955, 5, 266-270. 

Bushmakin, I. N. Voeikova, E. D. Liquid-vapor equilibria in the benzene - carbon tetrachloride system. L. J. Gen. Chem. USSR (Engl. Transl.) 1949, 19, 35-48. 

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