503-38-8 Usage
Description
Diphosgene (DP), trichloromethyl chloroformate, is a clear, colorless liquid with an odor similar to phosgene. It is noncombustible, a strong irritant to the eyes and tissues, and is toxic by inhalation and ingestion. DP has a boiling point of 127°C–128°C (263°F) and a vapor pressure of 4.2 at 68°F (20°C). The liquid density is 1.65, which is heavier than water, and a melting/freezing point of 314°F (157°C). Inhalation LC50 is 3600 mg/m3 for 10 min. Effects of exposure are quite similar to phosgene gas. Its molecular formula is ClCOOCCl3, and the structure and molecular formula are shown in Figure 8.38. The DOT lists diphosgene as a 6.1 poison liquid. The NFPA 704 designation for CG is estimated to be health 4, flammability 0, reactivity 1, and special 0. It has a four-digit UN identification number of 2972.
Chemical Properties
clear colorless liquid
Uses
Different sources of media describe the Uses of 503-38-8 differently. You can refer to the following data:
1. In organic synthesis; as war gas.
2. Trichloromethyl chloroformate is used as a reagent in the synthesis of organic compounds. It serves as a source of phosgene used in some laboratory preparations. Also, it is used as a reactant for the synthesis of cyclic carbamimidates, N-alkenyl and cycloalkyl carbamates and prostate-specific membrane antigen-targeted anticancer prodrugs. In addition, it is involved in the preparation of an erythromycin A derivatives and antibody-drug conjugates. It is utilized in the conversion of amines, carboxylic acids, formamides in to isocyanates, acid chlorides and isocyanides respectively.
3. Reactant for preparation of:Cyclic carbamimidates using a monophosphine gold(i) catalystN-Alkenyl and cycloalkyl carbamates as dual acting histamine H3 and H4 receptor ligandsProstate-specific membrane antigen-targeted anticancer prodrugsPotential west nile virus protease inhibitorsAntibody-drug conjugates (ADCs)Erythromycin A derivatives
Definition
diphosgene: A colourless liquid,ClCO.O.CCl3, originally used in 1916by Germany in World War I as achemical warfare agent. It is nowused as a reagent in organic synthesis.See also carbonyl chloride.
General Description
Colorless liquid, odorless to fruity.
Air & Water Reactions
Decomposes slowly in water or moist air (or when inhaled) to form very corrosive hydrogen chloride gas (hydrochloric acid) and carbon monoxide.
Fire Hazard
Some may burn but none ignite readily. Vapors from liquefied gas are initially heavier than air and spread along ground. Some of these materials may react violently with water. Cylinders exposed to fire may vent and release toxic and/or corrosive gas through pressure relief devices. Containers may explode when heated. Ruptured cylinders may rocket.
Check Digit Verification of cas no
The CAS Registry Mumber 503-38-8 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 5,0 and 3 respectively; the second part has 2 digits, 3 and 8 respectively.
Calculate Digit Verification of CAS Registry Number 503-38:
(5*5)+(4*0)+(3*3)+(2*3)+(1*8)=48
48 % 10 = 8
So 503-38-8 is a valid CAS Registry Number.
503-38-8Relevant articles and documents
Synthesis of Some Aromatic Diisocyanides with Trichloromethyl Chloroformate
Efraty, Avi,Feinstein, Irene,Wackerle, Lorenz,Goldman, Alexander
, p. 4059 - 4061 (1980)
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Process for preparing cyclopropylacetylene
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, (2008/06/13)
The invention relates to a process for the halogenation of cyclopropylmethyl ketone with at least one dihalo-triorganophosphorane of the general formula I R3PHal2??(I), in which the radicals R can be the same or different and denote a saturated or unsaturated aliphatic C1-C20hydrocarbon radical, a phenyl or (C1-C4alkyl)phenyl radical, which may be optionally substituted by one or two fluorine, chlorine and/or nitro groups, P stands for phosphorus and Hal denotes chlorine, bromine, or iodine, at a temperature of from 800° to 130° C., where the dihalo-triorganophosphane of the general formula (I) is synthesized in situ from triorganophosphane oxide or triorganophosphane sulfide of the general formula II R3PA ??(II), in which R is as defined above with respect to formula I and A denotes oxygen or sulfur, using a halogenating agent, wherein the triorganophosphane oxide or triorganophosphane sulfide is used in catalytic amounts, to the halogenation product of cyclopropylmethyl ketone obtained in said process, and to a process for the conversion of said halogenation product to cyclopropylacetytene.
Conversion of bis(trichloromethyl), carbonate to phosgene and reactivity of triphosgene, diphosgene, and phosgene with methanol
Pasquato,Modena,Cotarca,Delogu,Mantovani
, p. 8224 - 8228 (2007/10/03)
Triphosgene was decomposed quantitatively to phosgene by chloride ion. The reaction course was monitored by IR spectroscopy (React-IR), showing that diphosgene was an intermediate. The methanolysis of triphosgene in deuterated chloroform, monitored by proton NMR spectroscopy, gave methyl chloroformate and methyl 1,1,1-trichloromethyl carbonate in about a 1:1 ratio, as primary products. The reaction carried out in the presence of large excess of methanol (0.3 M, 30 equiv) was a pseudo-first-order process with a k(obs) of 1.0 x 10-4 s-1. Under the same conditions, values of k(obs) of 0.9 x 10-3 s-1 and 1.7 x 10-2 s-1 for the methanolysis of diphosgene and phosgene, respectively, were determined. The experimental data suggest that, under these conditions, the maximum concentration of phosgene during the methanolysis of triphosgene and diphosgene was lower than 1 x 10-5 M. Methyl 1,1,1-trichloromethyl carbonate was synthesized and characterized also by the APCI-MS technique.
