Triphosgene
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| Names | |
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| Preferred IUPAC name
Bis(trichloromethyl) carbonate | |
| Other names
BTC
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| Identifiers | |
3D model (JSmol)
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| ChemSpider | |
| ECHA InfoCard | 100.046.336 |
PubChem CID
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| C3Cl6O3 | |
| Molar mass | 296.748 g/mol |
| Appearance | white solid |
| Density | 1.780 g/cm3 |
| Melting point | 80 °C (176 °F; 353 K) |
| Boiling point | 206 °C (403 °F; 479 K) |
| Reacts | |
| Solubility | *soluble in dichloromethane[1] |
| Hazards | |
| GHS labelling: | |
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| Danger | |
| H314, H330[4] | |
| P260, P280, P284, P305+P351+P338, P310[4] | |
| Safety data sheet (SDS) | SDS Triphosgene |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references
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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.[5][6] Triphosgene is stable up to 200 °C.[7] Triphosgene is used in a variety of halogenation reactions.[8] Triphosgene is named this way because one equivalent of triphosgene behaves like three equivalents of phosgene. Triphosgene generates two equivalents of phosgene in situ, while the carbonate has the same reactivity as one equivalent of phosgene.
Preparation
This compound is commercially available. It is prepared by exhaustive free radical chlorination of dimethyl carbonate:[6]
- CH3OCO2CH3 + 6 Cl2 → CCl3OCO2CCl3 + 6 HCl
Triphosgene can be easily recrystallized from hot hexanes.
Uses
Triphosgene is used as a reagent in organic synthesis as a source of CO2+. It behaves like phosgene, to which it cracks thermally:
- OC(OCCl3)2 ⇌ 3 OCCl2
Alcohols are converted to carbonates. Primary and secondary amines are converted to ureas and isocyanates.[6][7][9][10]
Triphosgene has been used to synthesize chlorides.[8] Alkyl chlorides are produced from alcohols upon treatment with a mixture of triphosgene and pyridine. Alkyl dichlorides and trichlorides can similarly be prepared. Vinyl chlorides are synthesized from 2-epoxyketone using triphosgene and DMF to form the Vilsmeier reagent in situ.
Safety
The vapor pressure of Triphosgene is sufficiently high for it to reach concentrations that are considered toxicologically unsafe.[11] While several properties of triphosgene are not yet readily available, it is known that it is very toxic if inhaled. A toxic gas is emitted if it comes in contact with water.[12] There is a lack of information and variability regarding the proper handling of triphosgene. It is assumed to have the same risks as phosgene.[13][14]
See also
References
- ^ Ouimet MA, Stebbins ND, Uhrich KE (August 2013). "Biodegradable coumaric acid-based poly(anhydride-ester) synthesis and subsequent controlled release". Macromolecular Rapid Communications. 34 (15): 1231–1236. doi:10.1002/marc.201300323. PMC 3789234. PMID 23836606.
- ^ Tang S, Ikai T, Tsuji M, Okamoto Y (January 2010). "Immobilization and chiral recognition of 3,5-dimethylphenylcarbamates of cellulose and amylose bearing 4-(trimethoxysilyl)phenylcarbamate groups". Chirality. 22 (1): 165–172. doi:10.1002/chir.20722. PMID 19455617.
- ^ Zhou Y, Gong R, Miao W (September 2006). "New Method of Synthesizing N-Alkoxycarbonyl-N-arylamide with Triphosgene". Synthetic Communications. 36 (18): 2661–2666. doi:10.1080/00397910600764675. S2CID 98578315.
- ^ a b c Sigma-Aldrich Co., Triphosgene.
- ^ Roestamadji, Juliatiek; Mobashery, Shahriar (2001). "Bis(trichloromethyl) Carbonate". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rb200. ISBN 0-471-93623-5.
- ^ a b c Heiner Eckert; Barbara Forster (1987). "Triphosgene, a Crystalline Phosgene Substitute". Angew. Chem. Int. Ed. Engl. 26 (9): 894–895. doi:10.1002/anie.198708941.
- ^ a b Akiba T, Tamura O, Terashima S (1998). "(4R,5S)-4,5-Diphenyl-3-Vinyl-2-Oxazolidinone". Organic Syntheses. 75: 45. doi:10.15227/orgsyn.075.0045.
- ^ a b Ganiu MO, Nepal B, Van Houten JP, Kartika R (November 2020). "A decade review of triphosgene and its applications in organic reactions". Tetrahedron. 76 (47) 131553. doi:10.1016/j.tet.2020.131553. PMC 8054975. PMID 33883783.
- ^ Tsai JH, Takaoka LR, Powell NA, Nowick JS (2002). "Synthesis of Amino Acid Ester Isocyanates: Methyl (S)-2-Isocyanato-3-Phenylpropanoate". Organic Syntheses. 78: 220. doi:10.15227/orgsyn.078.0220.
- ^ Du H, Zhao B, Shi Y (2009). "Pd(0)-Catalyzed Diamination of Trans-1-Phenyl-1,3-Butadiene with Di-tert-Butyldiaziridinone as Nitrogen Source". Organic Syntheses. 86: 315. doi:10.15227/orgsyn.086.0315.
- ^ Cotarca L, Geller T, Répási J (2017-09-15). "Bis(trichloromethyl)carbonate (BTC, Triphosgene): A Safer Alternative to Phosgene?". Organic Process Research & Development. 21 (9): 1439–1446. doi:10.1021/acs.oprd.7b00220.
- ^ "Material Safety Data Sheet: Triphosgene" (PDF). Acros Organics. 2009. Retrieved February 17, 2022.
- ^ Damle SB (February 1993). "Safe handling of diphosgene, triphosgene". Chemical & Engineering News. 71 (6): 4.
- ^ Pauluhn J (February 2021). "Phosgene inhalation toxicity: Update on mechanisms and mechanism-based treatment strategies". Toxicology. 450 152682. Bibcode:2021Toxgy.45052682P. doi:10.1016/j.tox.2021.152682. PMID 33484734. S2CID 231693591.



