Belen’kii, L. I.; Gromova, G. P.; Krayushkin, M. M. published the artcile< Protonation and electrophilic trichloromethylation of 2,5- and 2,4-dichlorothiophenes>, Application In Synthesis of 31166-29-7, the main research area is electrophilic trichloromethylation chlorothiophene; protonation chlorothiophene.
Trichloromethylation of 2,5-dichlorothiophene (I) and 2,4-dichlorothiophene (II) with CCl4 and AlCl3 has been studied. The reaction of I was directed to position 3 with formation of 2,5-dichloro-3-(trichloromethyl)thiophene, the process being complicated by the formation of the isomeric 3,5-dichloro-2-(trichloromethyl)thiophene (III), and 4,5-dichloro-2-(trichloromethyl)thiophene, as well as linked products, i.e. a mixture of bis(dichlorothienyl)dichloromethanes. Trichloromethylation of II smoothly leads to III, along with a small amount of bis(3,5-dichloro-2-thienyl)dichloromethane. It was also found that as a result of protonation under the effect of HCland AlCl3, I was converted into II, which, under the reaction conditions exists in the form of σ-complex, i.e. the 2H-3,5-dichlorothiophenium ion, stable at room temperature The mechanism of trichloromethylation of I, including the ipso-attack by the CCl3+ cation and isomerization during protonation, is discussed.
Gazzetta Chimica Italiana published new progress about 31166-29-7. 31166-29-7 belongs to class chlorides-buliding-blocks, and the molecular formula is C5H2Cl2O2S, Application In Synthesis of 31166-29-7.
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics