Carbonyl dichloride

These substances have excellent solvent properties for nonpolar and slightly polar substances. Chloroform once was used widely as an inhalation anesthetic. However, it has a deleterious effect on the heart and is oxidized slowly by atmospheric oxygen to highly toxic carbonyl dichloride (phosgene, COCl2)-Commercial chloroform contains about 1% ethanol, which destroys any COCl2 formed by oxidation. 

Carbon tetrachloride commonly was employed as a cleaning solvent, although its considerable toxicity entails considerable hazard when used indiscriminately. It has been used as a fire-extinguishing fluid for petroleum fires, but its toxicity and tendency to form still more toxic carbonyl dichloride makes it undesirable for confined areas. The common laboratory practice of removing traces of water from solvents with metallic sodium should not be applied to halogenated compounds carbon tetrachloride-sodium mixtures are shock sensitive and can detonate. 

Exercise 16-9 Write equations to show the steps involved in the following carbonyl-addition reactions (a) base-catalyzed addition of ethanol to ethanal to form the corresponding hemiacetal, 1-ethoxyethanol (b) formation of 1-ethoxyethanol from ethanol and ethanal, but under conditions of acid catalysis (c) formation of 1,1-diethoxyethane from 1-ethoxyethanol and ethanol with an acid catalyst and (d) formation of diethyl carbonate (CH3CH20)2C—0 from ethanol and carbonyl dichloride. 

The phenylmethoxycarbonyl (benzyloxycarbonyl) group can be introduced by way of the corresponding acyl chloride, which is prepared from phenyl-methanol (benzyl alcohol) and carbonyl dichloride ... 

Phenylthallium diazide, 2279 Phenylthiophosphonic diazide, 2278 Phenylvanadium(V) dichloride oxide, 2239 Phosgene, see Carbonyl dichloride, 0328 Phospham, 4434 f Phosphine, 4503... 

B.13 2. B.14 3. A.01 3.A.02 3.A.03 3.A.04 3.B.05 3.B.06 3.B.07 3.A.08 3.A.09 3.A.10 3.A.11 Bis(2-hydroxyethyl)sulfide 3,3-Dimethyl-2-butanol Carbonyl dichloride Cyanogen chloride Hydrogen cyanide Trichloronitromethane Phosphorous oxychloride Phosphorous trichloride Phosphorous pentachloride Trimethyl phosphate Triethyl phosphate Dimethyl phosphate Diethyl phosphate... 

Carbonyl dichloride (phosgene) phosphoryl chloride/ phosphorus trichloride thiophosgene, thionyl chloride/ sulfur dichloride and cyanuric chloride react with carbodiimides to give the expected chloroformamidine derivatives. In the reaction of carbodiimides with two equivalents of carbonyl chloride N,N -disubstituted chloroformamidine N-carbonyl chlorides 703 are obtained. 

N-piCHLOROMETHYLENE)ANILINE PHENYL-CARBONIMIDIC DICHLORIDE N-PHEN XCARBO-NIiMIDIC DICHLORIDE PHENYL CARBYLAMINE CHLORIDE PHENYLCARBYLAMINE CHLORIDE POTI PHENYLIMIDOCARBONYL CHLORIDE N-PHENYLIMIDOPHOSGENE PHENYLIMINO-CARBONYL DICHLORIDE N-PHENYLIMINO-CARBONYL DICHLORIDE PHENYLISONITRILE DICHLORIDE... 

Acid anhydrides as activated derivatives of carboxylic acids have found little attention for the preparation of acid halides. Their use can be justified if they are obtained from other sources than from carboxylic acids, e.g. phthalic anhydride from the oxidation of naphthalene or o-xylene. It is, therefore, no surprise that there exist patents to convert phthalic anhydride to phthalic acid dichloride with carbonyl dichloride in the presence of catalysts. " However, there are some methods available thus a,a-di-chloromethyl methyl ether will convert acid anhydrides to acid chlorides and brenzcatechyl phosphorus tribromide will also achieve this transformation. Fluorides may be prepared similarly with the pyridine/HF mixture of 01ah. °... 

In principle Ae possibility of introducing a halocarbonyl into aromatic compounds with carbonyl dichloride in the presence of Lewis acids exists. In practice it is difficult to stop the reaction after the first electrophilic substitution, because the reaction piquets themselves can react further to give ketones. However, there are exceptions. Thiophene reacts with phosgene in the presence of aluminum trichloride to give 2-chlorocarbonylthiophene almost quantitatively. ... 

Carbonyl dichloride can be taken similarly to form acid anhydrides (equation 31). Via a mixed anhydride and in the presence of triethylamine, it is possible to prepare symmetrical anhydrides in high yield. ° °° A variation provides ethyl chloroformate as reagent.In a first step the carboxylic acid is ethoxycarbonylated in the presence of triethylamine and then reacted with free caiiioxylic acid to form the acid anhydride (equation 32). As the intermediate can be isolated, this is a good method of forming mixed anhydrides.In addition it seems to be particularly suitable for functionalized carboxylic acids such as hydroxy acids." Polymer-bound chloroformates may be advantageous in some cases. " " ... 

Common Name(s) Carbonic Dichloride, Carbonyl Dichloride, Chloroformyl Chloride, CG, D-Stoff, Green Cross, Phosgene... 

Carbonyl-bis(triphenylphosphine)iridium-silver diperchlorate, 3898 Carbonyl dichloride, 0329... 

A-Carbom ethoxy iminophosphoryl chloride, 0743 Carbonyl dichloride, 0329 Chlorotetralluorophosphorane, 3987... 

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