Diphosgene

Last updated
Diphosgene
Diphosgene structure.svg
Diphosgene-3D-vdW.png
Names
Preferred IUPAC name
Trichloromethyl carbonochloridate
Other names
Trichloromethyl chloroformate, surpalite
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.007.242 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 207-965-9
PubChem CID
RTECS number
  • LQ7350000
UNII
  • InChI=1S/C2Cl4O2/c3-1(7)8-2(4,5)6 Yes check.svgY
    Key: HCUYBXPSSCRKRF-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C2Cl4O2/c3-1(7)8-2(4,5)6
    Key: HCUYBXPSSCRKRF-UHFFFAOYAO
  • ClC(=O)OC(Cl)(Cl)Cl
Properties
C2Cl4O2
Molar mass 197.82 g/mol
Appearanceliquid at room temperature
Density 1.65 g/cm3
Melting point −57 °C (−71 °F; 216 K)
Boiling point 128 °C (262 °F; 401 K)
insoluble, reacts
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
highly toxic, maybe corrosive; asphyxiant
GHS labelling:
GHS-pictogram-acid.svg GHS-pictogram-skull.svg
Danger
H300, H301, H314, H330
P260, P264, P270, P271, P280, P284, P301+P310, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P320, P321, P330, P363, P403+P233, P405, P501
Flash point 32 °C (90 °F; 305 K)
Related compounds
Related compounds
COCl2, Cl2
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Diphosgene is an organic chemical compound with the formula ClCO2CCl3. This colorless liquid is a valuable reagent in the synthesis of organic compounds. Diphosgene is related to phosgene and has comparable toxicity, but is more conveniently handled because it is a liquid, whereas phosgene is a gas.

Contents

Production and uses

Diphosgene is prepared by radical chlorination of methyl chloroformate under UV light: [1]

Cl-CO-OCH3 + 3 Cl2 —(hv)→ Cl-CO-OCCl3 + 3 HCl

Another method is the radical chlorination of methyl formate: [2]

H-CO-OCH3 + 4 Cl2 —(hv)→ Cl-CO-OCCl3 + 4 HCl

Diphosgene converts to phosgene upon heating or upon catalysis with charcoal. It is thus useful for reactions traditionally relying on phosgene. For example, it convert amines into isocyanates, secondary amines into carbamoyl chlorides, carboxylic acids into acid chlorides, and formamides into isocyanides. Diphosgene serves as a source of two equivalents of phosgene:

2 RNH2 + ClCO2CCl3 → 2 RNCO + 4 HCl

With α-amino acids diphosgene gives the acid chloride-isocyanates, OCNCHRCOCl, or N-carboxy-amino acid anhydrides depending on the conditions. [3]

It hydrolyzes to release HCl in humid air.

Diphosgene is used in some laboratory preparations because it is easier to handle than phosgene.

Role in warfare

Diphosgene was originally developed as a pulmonary agent for chemical warfare, a few months after the first use of phosgene. It was used as a poison gas in artillery shells by Germany during World War I. The first recorded battlefield use was in May 1916. [4] Diphosgene was developed because the vapors could destroy the filters in gas masks in use at the time.

Safety

Diphosgene has a relatively high vapor pressure of 10 mm Hg (1.3 kPa) at 20 °C and decomposes to phosgene around 300 °C. Exposure to diphosgene is similar in hazard to phosgene.

See also

Related Research Articles

<span class="mw-page-title-main">Phosgene</span> Toxic gaseous compound (COCl2)

Phosgene is an organic chemical compound with the formula COCl2. It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. It can be thought of chemically as the double acyl chloride analog of carbonic acid, or structurally as formaldehyde with the hydrogen atoms replaced by chlorine atoms. Phosgene is a valued and important industrial building block, especially for the production of precursors of polyurethanes and polycarbonate plastics.

In organic chemistry, an acyl chloride is an organic compound with the functional group −C(=O)Cl. Their formula is usually written R−COCl, where R is a side chain. They are reactive derivatives of carboxylic acids. A specific example of an acyl chloride is acetyl chloride, CH3COCl. Acyl chlorides are the most important subset of acyl halides.

<span class="mw-page-title-main">Acyl halide</span> Oxoacid compound with an –OH group replaced by a halogen

In organic chemistry, an acyl halide is a chemical compound derived from an oxoacid by replacing a hydroxyl group with a halide group.

Organochlorine chemistry is concerned with the properties of organochlorine compounds, or organochlorides, organic compounds containing at least one covalently bonded atom of chlorine. The chloroalkane class includes common examples. The wide structural variety and divergent chemical properties of organochlorides lead to a broad range of names, applications, and properties. Organochlorine compounds have wide use in many applications, though some are of profound environmental concern, with TCDD being one of the most notorious.

<span class="mw-page-title-main">Triphosgene</span> Chemical compound

Triphosgene (bis(trichloromethyl) carbonate (BTC) is a chemical compound with the formula OC(OCCl3)2. It is used as a solid substitute for phosgene, which is a gas and diphosgene, which is a liquid. Triphosgene is stable up to 200 °C. Triphosgene is used in a variety of halogenation reactions.

<span class="mw-page-title-main">Copper(II) chloride</span> Chemical compound

Copper(II) chloride, also known as cupric chloride, is an inorganic compound with the chemical formula CuCl2. The monoclinic yellowish-brown anhydrous form slowly absorbs moisture to form the orthorhombic blue-green dihydrate CuCl2·2H2O, with two water molecules of hydration. It is industrially produced for use as a co-catalyst in the Wacker process.

<span class="mw-page-title-main">Oxalyl chloride</span> Chemical compound

Oxalyl chloride is an organic chemical compound with the formula Cl−C(=O)−C(=O)−Cl. This colorless, sharp-smelling liquid, the diacyl chloride of oxalic acid, is a useful reagent in organic synthesis.

<span class="mw-page-title-main">Thionyl chloride</span> Inorganic compound (SOCl2)

Thionyl chloride is an inorganic compound with the chemical formula SOCl2. It is a moderately volatile, colourless liquid with an unpleasant acrid odour. Thionyl chloride is primarily used as a chlorinating reagent, with approximately 45,000 tonnes per year being produced during the early 1990s, but is occasionally also used as a solvent. It is toxic, reacts with water, and is also listed under the Chemical Weapons Convention as it may be used for the production of chemical weapons.

<span class="mw-page-title-main">Benzoyl chloride</span> Organochlorine compound (C7H5ClO)

Benzoyl chloride, also known as benzenecarbonyl chloride, is an organochlorine compound with the formula C7H5ClO. It is a colourless, fuming liquid with an irritating odour, and consists of a benzene ring with an acyl chloride substituent. It is mainly useful for the production of peroxides but is generally useful in other areas such as in the preparation of dyes, perfumes, pharmaceuticals, and resins.

<span class="mw-page-title-main">Benzyl chloroformate</span> Chemical compound

Benzyl chloroformate, also known as benzyl chlorocarbonate or Z-chloride, is the benzyl ester of chloroformic acid. It can be also described as the chloride of the benzyloxycarbonyl group. In its pure form it is a water-sensitive oily colorless liquid, although impure samples usually appear yellow. It possesses a characteristic pungent odor and degrades in contact with water.

<span class="mw-page-title-main">Trimethylsilyl chloride</span> Organosilicon compound with the formula (CH3)3SiCl

Trimethylsilyl chloride, also known as chlorotrimethylsilane is an organosilicon compound, with the formula (CH3)3SiCl, often abbreviated Me3SiCl or TMSCl. It is a colourless volatile liquid that is stable in the absence of water. It is widely used in organic chemistry.

Benzyl chloride, or α-chlorotoluene, is an organic compound with the formula C6H5CH2Cl. This colorless liquid is a reactive organochlorine compound that is a widely used chemical building block.

<span class="mw-page-title-main">Vanadium oxytrichloride</span> Chemical compound

Vanadium oxytrichloride is the inorganic compound with the formula VOCl3. This yellow distillable liquid hydrolyzes readily in air. It is an oxidizing agent. It is used as a reagent in organic synthesis. Samples often appear red or orange owing to an impurity of vanadium tetrachloride.

Dimethyldichlorosilane is a tetrahedral organosilicon compound with the formula Si(CH3)2Cl2. At room temperature it is a colorless liquid that readily reacts with water to form both linear and cyclic Si-O chains. Dimethyldichlorosilane is made on an industrial scale as the principal precursor to dimethylsilicone and polysilane compounds.

<span class="mw-page-title-main">Methyltrichlorosilane</span> Chemical compound

Methyltrichlorosilane, also known as trichloromethylsilane, is a monomer and organosilicon compound with the formula CH3SiCl3. It is a colorless liquid with a sharp odor similar to that of hydrochloric acid. As methyltrichlorosilane is a reactive compound, it is mainly used a precursor for forming various cross-linked siloxane polymers.

Methanesulfonyl chloride is an organosulfur compound with the formula CH3SO2Cl. Using the organic pseudoelement symbol Ms for the methanesulfonyl group CH3SO2–, it is frequently abbreviated MsCl in reaction schemes or equations. It is a colourless liquid that dissolves in polar organic solvents but is reactive toward water, alcohols, and many amines. The simplest organic sulfonyl chloride, it is used to make methanesulfonates and to generate the elusive molecule sulfene.

<span class="mw-page-title-main">Chloroformate</span>

Chloroformates are a class of organic compounds with the formula ROC(O)Cl. They are formally esters of chloroformic acid. Most are colorless, volatile liquids that degrade in moist air. A simple example is methyl chloroformate, which is commercially available.

<span class="mw-page-title-main">Methyl chloroformate</span> Chemical compound

Methyl chloroformate is a chemical compound with the chemical formula Cl−C(=O)−O−CH3. It is the methyl ester of chloroformic acid. It is an oily colorless liquid, although aged samples appear yellow. It is also known for its pungent odor.

<span class="mw-page-title-main">Carbamoyl chloride</span>

A carbamoyl chloride is the functional group with the formula R2NC(O)Cl. The parent carbamoyl chloride, H2NCOCl is unstable, but many N-substituted analogues are known. Most examples are moisture sensitive, colourless, and soluble in nonpolar organic solvents. An example is dimethylcarbamoyl chloride (m.p. −90 °C and b.p. 93 °C). Carbamoyl chlorides are used to prepare a number of pesticides, e.g. carbofuran and aldicarb.

<span class="mw-page-title-main">Propionyl chloride</span> Chemical compound

Propionyl chloride (also propanoyl chloride) is the organic compound with the formula CH3CH2C(O)Cl. It is the acyl chloride derivative of propionic acid. It undergoes the characteristic reactions of acyl chlorides. It is a colorless, corrosive, volatile liquid.

References

  1. Keisuke Kurita and Yoshio Iwakura (1979). "Trichloromethyl Chloroformate as a Phosgene Equivalent: 3-Isocyanatopropanoyl Chloride". Organic Syntheses . 59: 195.; Collective Volume, vol. 6, p. 715
  2. Lohs, K. H.: Synthetische Gifte; Berlin (east), 1974 (German).
  3. Kurita, K. "Trichloromethyl Chloroformate" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. doi : 10.1002/047084289X.
  4. Jones, Simon; Hook, Richard (2007). World War I Gas Warfare Tactics and Equipment. Osprey Publishing. ISBN   978-1-84603-151-9.