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Chloromethyl methyl ether

Chloromethyl methyl ether[1]
Skeletal formula of chloromethyl methyl ether
Ball-and-stick model of the chloromethyl methyl ether molecule
Names
Preferred IUPAC name
Chloro(methoxy)methane
Other names
MOM-Cl, CMME, MCD, Chlorodimethyl ether, Chloromethoxymethane, Dimethylchloroether, Methylchloromethyl ether
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.003.165 Edit this at Wikidata
EC Number
  • 203-480-1
KEGG
RTECS number
  • KN6650000
UNII
UN number 1239
  • InChI=1S/C2H5ClO/c1-4-2-3/h2H2,1H3 ☒N
    Key: XJUZRXYOEPSWMB-UHFFFAOYSA-N ☒N
  • InChI=1/C2H5ClO/c1-4-2-3/h2H2,1H3
    Key: XJUZRXYOEPSWMB-UHFFFAOYAK
  • COCCl
Properties
C2H5ClO
Molar mass 80.51 g·mol−1
Appearance Colorless liquid
Odor Irritating and acrid
Density 1.06 g/mL
Melting point −103.5 °C (−154.3 °F; 169.7 K)
Boiling point 55–57 °C (131–135 °F; 328–330 K)
reacts
Solubility Soluble in alcohol and diethylether
Vapor pressure 192 mmHg (21°C)[2]
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Carcinogen & Irritant
GHS labelling:
GHS02: FlammableGHS07: Exclamation markGHS08: Health hazard
Danger
H225, H302, H312, H319, H332, H350
P201, P202, P210, P233, P240, P241, P242, P243, P261, P264, P270, P271, P280, P281, P301+P312, P302+P352, P303+P361+P353, P304+P312, P304+P340, P305+P351+P338, P308+P313, P312, P322, P330, P337+P313, P363, P370+P378, P403+P235, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g. gasolineInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazards (white): no code
3
3
2
Flash point 0 °C (32 °F; 273 K) (open cup)[2]
NIOSH (US health exposure limits):
PEL (Permissible)
 OSHA-Regulated Carcinogen, no PEL[2]
REL (Recommended)
 Carcinogenic[2]
IDLH (Immediate danger)
 N.D.[2]
Safety data sheet (SDS) Safety Data Sheet Archived
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Chloromethyl methyl ether (CMME) is a compound with formula CH3OCH2Cl. A colorless liquid, it is a chloroalkyl ether. It is used as an alkylating agent. In organic synthesis, it is used for introducing the methoxymethyl ether (MOM) protecting group,[3] and is thus often called MOM-Cl or MOM chloride. It also finds application as a chloromethylating agent in some variants of the Blanc chloromethylation.[4]

Preparation

A convenient synthesis of chloromethyl methyl ether in situ involves the reaction of dimethoxymethane and acetyl chloride in the presence of a Lewis acid catalyst[5] This route affords a methyl acetate solution of chloromethyl methyl ether of high purity. A similar method, using a high-boiling acyl chloride, can be used to prepare pure, dimethoxymethane being the only contaminant.[6] In contrast, the classical procedure reported in Organic Syntheses employing formaldehyde, methanol, and hydrogen chloride yields material significantly contaminated with the dangerous bis(chloromethyl) ether and requires fractional distillation.[7]

Safety

The amount of time required to destroy residual chloromethyl methyl ether using various standard aqueous quench solutions (ammonium chloride solution, water, and sodium carbonate solution) has been measured. In all cases, a solution of chloromethyl methyl ether in toluene/methyl acetate was destroyed (to within detection limit) after vigorous stirring with the quench solution for 15 minutes.[5]

CMME is a known human carcinogen.[8] Chronic exposure can increase the incidence of respiratory cancers, including small cell carcinoma.[9] It is one of 13 chemicals regulated by the Occupational Safety and Health Administration despite not having an established permissible exposure limit.[10][11]

It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities.[12] It listed in Schedule 1 Part 1 of Canada's Prohibition of Certain Toxic Substances Regulations.[13]

References

  1. ^ Sigma-Aldrich
  2. ^ a b c d e NIOSH Pocket Guide to Chemical Hazards. "#0129". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ Protective Groups in Organic Synthesis, T. W. Greene and P. G. M. Green, 3rd Edition, pages 27-33. ISBN 0-471-16019-9
  4. ^ Wuts, Peter G. M. (2001). "Chloromethyl Methyl Ether". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rc118. ISBN 0471936235.
  5. ^ a b Berliner, Martin A.; Belecki, Katherine (2007). "Synthesis of alpha-Halo Ethers from Symmetric Acetals and in situ Methoxymethylation of an Alcohol". Organic Syntheses. 84: 102. doi:10.15227/orgsyn.084.0102.
  6. ^ R.J. Linderman, M. Jaber, B.D. Griedel, J. Org. Chem. 1994, 59, 6499-6500.
  7. ^ C. S. Marvel and P. K. Porter (1929). "Monochloromethyl Ether". Organic Syntheses. 9: 58. doi:10.15227/orgsyn.009.0058.
  8. ^ bis(Chloromethyl) Ether and Technical-Grade Chloromethyl Methyl Ether CAS Nos. 542-88-1 and 107-30-2 Report on carcinogens, eleventh edition
  9. ^ "Chloromethyl methyl ether". U.S. Environmental Protection Agency, Integrated Risk Information System. 7 March 2011. Accessed 3 May 2011.
  10. ^ NIOSH Pocket Guide to Chemical Hazards
  11. ^ Appendix B - Thirteen OSHA-Regulated Carcinogens
  12. ^ "40 C.F.R.: Appendix A to Part 355—The List of Extremely Hazardous Substances and Their Threshold Planning Quantities" (PDF) (July 1, 2008 ed.). Government Printing Office. Archived from the original (PDF) on February 25, 2012. Retrieved October 29, 2011. {{cite journal}}: Cite journal requires |journal= (help)
  13. ^ http://laws-lois.justice.gc.ca/PDF/SOR-2012-285.pdf [bare URL PDF]
Quelle: https://en.wikipedia.org/wiki/Chloromethyl_methyl_ether