COCH2Cl

COCH2Cl is the SMILES notation for chloromethyl methyl ether, a chemical reagent commonly referred to as chloromethyl methyl ether (CMME) or methoxymethyl chloride (MOMCl). Its formula is C2H5ClO, and in structure it corresponds to CH3-O-CH2-Cl, an ether with a chloromethyl substituent.

Chomically, CH3-O-CH2-Cl is a reactive chloromethyl ether used primarily to install the methoxymethyl (MOM) protecting group on alcohols in organic synthesis. The MOM group (RO-CH2-O-CH3) protects hydroxyl functionalities during multi-step sequences and can be removed under acidic or mildly acidic conditions. As a reagent for MOM protection, CMME is often employed in routes where selective deprotection later is required.

Safety and regulatory status are central considerations. Chloromethyl methyl ether is a highly toxic, mutagenic and potentially carcinogenic compound. It is also a potent alkylating agent and poses significant inhalation, skin, and eye hazards. Its handling requires strict engineering controls, personal protective equipment, and use within properly functioning fume hoods. Because of its hazards, many regulatory frameworks limit its production, distribution, and laboratory use, and safer alternatives are sought where possible.

Synthesis, storage, and disposal of CMME are typically governed by institutional safety protocols and national regulations. Alternatives for MOM protection, as well as developments in safer chloromethylating reagents, are part of ongoing efforts to minimize risk in synthetic chemistry.

See also: methoxymethyl protecting group, MOMCl, chloromethyl ethers.