Bischloromethyl ether

Ethers are formed in the usual way (125). The bischloromethyl ether is obtained using formaldehyde and hydrogen chloride (86). 

CautionI Bischloromethyl ether is a mild lackrymator. Appropriate precautions should be taken. 

Bischloromethyl ether has been prepared by saturation of formalin with dry hydrogen chloride by the reaction of paraformaldehyde with phosphorus trichloride or phosphorus oxychloride, by solution of paraformaldehyde in concentrated sulfuric acid and treatment with ammonium chloride or dry hydrogen chloride, and by suspension of paraformaldehyde in seventy or eighty percent sulfuric acid and treatment with chlorosulfonic acid. It is formed together with the asymmetrical isomer when methyl ether is chlorinated and when paraformaldehyde is treated with chlorosulfonic acid. The present method has been published. ... 

Biphenylyl)urea, 31,10 l-(4-Biphenylyl)urea, 31,10 Bis-4-chIorobutyl ether, 37, 55 Bischloromethyl ether, 36,1 N,N -Bis-2-cyanoethyl-a-phenylene-... 

Chloromethylation of selenophene, like other electrophilic substitutions, occurs at the a position, and 2-chloromethylselenophene is formed together with small amounts of the 2,5-bischloromethyl derivative. Selenophene and its homologs have been chloromethyl-ated by diverse reagents formalin and hydrogen chloride, a mixture of mono- and bischloromethyl ether, or formaldehyde bischloro-methylacetal. A mixture of mono- and bischloromethyl ether is the most convenient reagent. 

The same name would ordinarily be used even if the polymer were synthesized from ethylene glycol (HOCH2CH2OH), ethylene chlorohydrin (CICH2CH2OH), or bischloromethyl ether (CICH2OCH2CI). Similarly, structure 1-13 is called polycaprolactam because it is made industrially from the lactam by reaction (1-5), in preference to polymerization of the parent amino acid, H2N (CH2).[Pg.29]

When thiophene or a simple alkylthiophene is treated with chloromethyl ether or bischloromethyl ether, the expected chloromethylthiophene is usually accompanied by some of the related dithienylmethane. From thiophene itself the quantity of 2,2 dithienylmethane produced is very small,47 but Cagniant and Cagniant48 found that 5,5 diethyl-2,2 -dithienylmethane was the major product (57%) from 2-ethylthiophene. 

The conflicting reports of the results of the chloromethylation of 2,5-dimethylthiophene with formaldehyde-hydrochloric acid have already been mentioned. With bischloromethyl ether in acetic acid this substance gives a mixture of 3-chloromethyl-2,5-dimethylthiophene (46%), 3,4-bis(chloro-methyl)-2,5-dimethylthiophene (12%), and 4-chloromethyl-5,5 -dimethyl-2,2 -dithienylmethane (15)49 (19%). 2,5-Diethylthiophene, on the other hand, yields only a very small quantity of a dithienylmethane under these conditions. The formation of a chloromethylated dithienylmethane was also observed in the bischloromethyl ether treatment of 2-ethylthiothiophene.50 The product, 16, was not actually isolated, but its presence was demonstrated by further reactions (see Section III,D) the yields in these reactions imply that 16 was a rather minor component in the crude reaction mixture. 

CAUTION Bischloromethyl ether has been reported to have carcinogenic properties. 

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