Methyl 1,1,1-trichloromethyl carbonate

Triphosgene is quantitatively converted to phosgene by catalysts such as chloride ion [2-4]. The reaction course has been monitored by IR spectroscopy (React-IR), which showed diphosgene to be an intermediate. The methanolysis of triphosgene in deuterated chloroform, as monitored by NMR spectroscopy, gave as primary products methyl chloroformate and methyl 1,1,1-trichloromethyl carbonate in about a 1 1 ratio. The reaction carried out in the presence of a large excess of... 

Like the preceding compound, trichloro methyl chloroformate reacts with sodium phenate, forming sodium chloride and phenyl trichloromethyl carbonate ... 

Methanol forms trichloromethyl carbonate and methyl chloroformate ... 

In presence of excess methanol, the trichloromethyl carbonate is converted into methyl carbonate and methyl chloroformate, so that the final product of the reaction with excess methanol present is methyl carbonate. 

Solid bis(trichloromethyl) carbonate as phosgene equivalent) added under Nj to a stirred soln. of cyclohexanecarboxaldehyde and a little pyridine in carbon tetrachloride at —20 at such a rate that the temp, remained at —10° to —20°, the viscous slurry allowed to warm to room temp, over 90 min, heated to 40° for 1 h, cooled to room temp., and stirred overnight cyclohexyl(chloro)methyl chloroformate. Y 89%. The method is mild, high-yielding, and avoids the use of hazardous phosgene. F.e.s. M.J. Coghlan, B.A. Caley, Tetrahedron Letters 30, 2033-6 (1989). 

BenZotrichloride Method. The central carbon atom of the dye is supphed by the trichloromethyl group from iJ-chlorobenzotrichloride. Both symmetrical and unsymmetrical triphenyhnethane dyes suitable for acryhc fibers are prepared by this method. 4-Chlorobenzotrichloride is condensed with excess chlorobenzene in the presence of a Lewis acid such as aluminium chloride to produce the intermediate aluminium chloride complex of 4,4, 4"-trichlorotriphenylmethyl chloride (18). Stepwise nucleophihc substitution of the chlorine atoms of this intermediate is achieved by successive reactions with different arylamines to give both symmetrical (51) and unsymmetrical dyes (52), eg, N-(2-chlorophenyl)-4-[(4-chlorophenyl) [4-[(3-methylphenyl)imino]-2,5-cyclohexadien-l-yhdene]methyl]benzenaminemonohydrochloride [85356-86-1J (19) from. w-toluidine and o-chloroaniline. 

Amidines are converted into 1,2,4-thiadiazoles by reaction with isothiocyanates, iminosulfenyl chlorides, di- and trichloromethyl sulfenyl chlorides, and carbon disulfide in the presence of sulfur <82AHC(32)285> for example, 5-mercapto-3-methyl-l,2,4-thiadiazole (205) is obtained by the treatment of acetamidine with carbon disulfide and sulfur under basic conditions (Equation (29)) <85JAP85255783>. A useful method for the synthesis of 5-chloro-l, 2,4-thiadiazole (206) (R = 6-methyl-2-pyridyl) involves the reaction of amidines with trichloromethylsulfenyl chloride (Equation (30)) <91JAP9183590>. 

It is interesting to note that the complex of the composition [CioHio(CC13)Co] obtained previously (137) by reaction of carbon tetrachloride with cobaltocene is the 1-endo-trichloromethyl analogue of complex (XXIV) this complex can be reduced by lithium aluminium hydride to the l-endo-dichloro-methyl derivative (99). 

Photolysis of this polymer gives radicals on which side chains can be formed, giving graft polymerization 122, 123, 153). Similarly the polymerization of styrene (152) or vinyl acetate (157) in the presence of bromotrichloromethane gives telomers carrying terminal bromine atoms and trichloromethyl groups. By ultraviolet irradiation (3500 A) in the presence of methyl methacrylate the carbon-bromine links are broken and block copolymers are formed. The telomerization of acrylonitrile and acrylic acid with bromoform is based on the same technique the end groups of both polyacrylonitrile and polyacrylic acid were photolyzed in the presence of acrylamide and afforded polyacrylamide blocks linked to polyacrylonitrile or polyacrylic acid blocks (164, 165). 

Bands at 1240 and 710 cm have been observed for the trifluoro-methyl radical, CFj, trapped in a matrix of carbon dioxide. These bands con espond very closely to those observed by Milligan et al. (1966) for this radical (1250 and 710 cm ). A band has been observed at 897 cm for the trichloromethyl radical, CCI3, trapped in a matrix of carbon dioxide. Andrews (1968) has obtained a similar band at 898 cm" for this radical. 

It is obtained as a by-product in the preparation of trichloromethyl chloroformate when methyl chloroformate which is impure with dimethyl carbonate is employed. 

Sulfones undergo peculiar reactions on treatment with carbon tetrachloride and potassium hydroxide in aqueous rm-butyl alcohol at 25-80 °C. Methyl phenyl sulfone yields phenyl trichloromethyl sulfone, which is hydrolyzed to benzenesulfonic acid [954. Dibenzyl sulfone is quantitatively converted into fran -stilbene, and dicyclohexyl sulfone is converted into a mixture of bicyclohexylidene and l,l-dichloro-2,3-dicyclohexylcy-clopropane [954] (equations 582-584). 

Chlorine is virtually absent in the copolymer produced in the azobisisobutyronitrile (AIBN) catalyzed copolymerization of styrene and maleic anhydride in the presence of chloroform or carbon tetrachloride (3, 4), or of p-dioxene and maleic anhydride in the presence of acrylonitrile in chloroform (5). This absence indicates that trichloromethyl radicals generated by the reaction of the chlorinated hydrocarbons with the radicals from AIBN are not incorporated into the polymer chain. Similarly, there is little or no cnlorine in the alternating copolymer that is formed in the copolymerization of styrene and methyl methacrylate in the presence of ethylaluminum sesquichloride (EASC) in the presence of chloroform and carbon tetrachloride, and with or without a peroxide initiator (6). 

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