Chemical structure of chloromethyl methyl ether (MOM-Cl)

Chloroalkyl ethers are a class of organic compounds with the general structure R-O-(CH₂)_n-Cl, characterized as an ether connected to a chloromethyl group via an alkane chain.

Chloromethyl methyl ether (CMME) is an ether with the formula CH₃OCH₂Cl. It is used as an alkylating agent and industrial solvent to manufacture dodecylbenzyl chloride, water repellents, ion-exchange resins, polymers, and as a chloromethylation reagent. In organic synthesis the compound is used for the introduction of the methoxymethyl (MOM) protecting group.

Closely related compounds of industrial importance are bis(chloromethyl) ether (BCME) (closely related to chemical weapon sulfur mustard)^[1] and benzyl chloromethyl ether (BOMCl).

Chloromethyl ether	R		Molar mass	CAS number	Boiling point °C
Benzyl chloromethyl ether	Benzyl		156.61	3587-60-8	102 °C @ 14 mmHg (1.9 kPa)
Chloromethyl methyl ether	Methyl		80.51	107-30-2	55-57
Bis(chloromethyl) ether			114.96	542-88-1	106
tert-Butyl chloromethyl ether	Butyl		124.5
2-Methoxyethoxymethyl chloride			124.57	3970-21-6	50-52 °C @ 13 mmHg (1.7 kPa)
Dichloromethyl methyl ether			114.96	4885-02-3	82 - 85.5 °C
Representative chloroalkyl ethers[2]

Methoxymethyl ethers (MOMs) and methoxyethyl ethers (MEMs) are common protecting groups in organic synthesis.

Safety

Chloroalkyl ethers are strong alkylating agents with attendant dangers. These compounds are human carcinogen.^[3]

References