Methyl chloroformate

Structural formula
General
Surname	Methyl chloroformate
other names	Methyl chlorocarbonate; Methyl chloromethanate; Methyl chloroformate; Methoxycarbonyl chloride; Methyl chloromethanoate;
Molecular formula	C 2 H 3 ClO 2
Brief description	colorless liquid with a pungent odor
External identifiers / databases
EC number	201-187-3
ECHA InfoCard	100.001.080
PubChem	6586
Wikidata	Q419678
properties
Molar mass	94.5 g · mol -1
Physical state	liquid
density	1.22 g cm −3 (20 ° C)
Melting point	−61 ° C
boiling point	72 ° C
Vapor pressure	127 hPa (20 ° C); 505 hPa (50 ° C); 915 hPa (65 ° C);
solubility	heavy in water (5 g l −1 at 20 ° C); soluble in methanol , ethanol , benzene , carbon tetrachloride , fat; miscible with almost all common aprotic solvents;
Refractive index	1.3868 (20 ° C)
safety instructions
H and P phrases	H: 225-300-312-330-314
	P: 210-280-305 + 351 + 338-310
MAK	DFG / Switzerland: 0.2 ml m −3 or 0.78 mg m −3
Toxicological data	60 mg kg −1 ( LD 50 , rat , oral )
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Methyl chloroformate is a chemical compound that is used as an intermediate in the production of various carbonic acid derivatives. The compound belongs to the group of chloroformic acid esters , as well as chloroformic acid ethyl ester , chloroformic acid n- butyl ester , chloroformic acid benzyl ester and chloroformic acid phenyl ester .

Extraction and presentation

Methyl chloroformate is obtained from phosgene and anhydrous methanol .

properties

Chemical properties

Methyl chloroformate slowly hydrolyzes with water to give methanol , hydrogen chloride and carbon dioxide. With steam, the hydrolysis takes place violently with decomposition and foaming. The compound decomposes when exposed to heat, releasing hydrogen chloride, phosgene, chlorine and other toxic substances.

Safety-related parameters

Methyl chloroformate forms highly flammable vapor-air mixtures. The compound has a flash point of 10 ° C. The explosion range is between 7.5% by volume (293 g / m ³ ) as the lower explosion limit (LEL) and 26% by volume (1020 g / m ³ ) as the upper explosion limit (UEL).) The limit gap width was set to 1 , 2 mm determined. This results in an assignment to explosion group IIA. The ignition temperature is 475 ° C. The substance therefore falls into temperature class T1.

use

Methyl chloroformate is used as a common intermediate in the preparation of carbonates and carbamates , dyes, and drugs, the pesticides asulam , benomyl , carbendazim , hexazinone , phenmedipham , pyrazosulfuron-ethyl , thiophanate-methyl , triflusulfuron-methyl , zinc-organic reagents with the help of electrochemical Methods and as a dehydrating agent in the manufacture of 2-hydroxybenzonitrile .

nomenclature

The common name “methyl chloroformate” is incorrect, as it is a derivative of carbonic acid , not a derivative of formic acid . It is the monochloride and at the same time the monomethyl ester of carbonic acid.

Individual evidence

↑ Data sheet for methyl chloroformate (PDF) from Merck , accessed on May 2, 2014.
↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p Entry on methyl chloroformate in the GESTIS substance database of the IFA , accessed on January 9, 2019(JavaScript required) .
↑ ^a ^b ^c Toxicological assessment of methyl chloroformate (PDF) at the professional association for raw materials and chemical industry (BG RCI), accessed on May 2, 2014.
↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-344.
↑ Entry on methyl chloroformate in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
↑ Data sheet Methyl chloroformate from Sigma-Aldrich , accessed on May 2, 2014 ( PDF ).
↑ Swiss Accident Insurance Fund (Suva): Limit values - current MAK and BAT values (search for 79-22-1 or methyl chloroformate ), accessed on November 2, 2015.
↑ ^a ^b ^c E. Brandes, W. Möller: Safety-related parameters. Volume 1: Flammable Liquids and Gases. Wirtschaftsverlag NW - Verlag für neue Wissenschaft, Bremerhaven 2003.
↑ chemicalland21.com: METHYL CHLOROFORMATE , accessed on May 2, 2014.

[Merck-1] Data sheet for methyl chloroformate (PDF) from Merck , accessed on May 2, 2014.

[GESTIS-2] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p Entry on methyl chloroformate in the GESTIS substance database of the IFA , accessed on January 9, 2019(JavaScript required) .

[bg-3] Toxicological assessment of methyl chloroformate (PDF) at the professional association for raw materials and chemical industry (BG RCI), accessed on May 2, 2014.

[CRC90_3_344-4] David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-344.

[CLP_100.001.080-5] Entry on methyl chloroformate in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .

[Sigma-6] Data sheet Methyl chloroformate from Sigma-Aldrich , accessed on May 2, 2014 ( PDF ).

[7] Swiss Accident Insurance Fund (Suva): Limit values - current MAK and BAT values (search for 79-22-1 or methyl chloroformate ), accessed on November 2, 2015.

[Brandes-8] E. Brandes, W. Möller: Safety-related parameters. Volume 1: Flammable Liquids and Gases. Wirtschaftsverlag NW - Verlag für neue Wissenschaft, Bremerhaven 2003.

[9] 21.com: METHYL CHLOROFORMATE , accessed on May 2, 2014.