Bunnett, J. F.; Bachman, D. M.; Snipper, L. P.; Maloney, J. H. published the artcile< Chlorination of 2-thiophenecarboxylic acid>, COA of Formula: C5H2Cl2O2S, the main research area is .
2-Thiophenecarboxylic acid (I) 3 g. (0.023 mole), NaOCl 0.042 mole, and excess NaOH in 400 cc. total volume were treated at pH 11.0 and 48° with 25 cc. 6 N HCl for 6 min. The temperature rose to 53°, the pH dropped to 1.3, and a white precipitate formed. After addition of 5 cc. 6 N HCl and 107 g. NaCl, the mixture was cooled and filtered to give 1.75 g. (46%) 5-chloro-2-thiophenecarboxylic acid (II), m. 134-7°, and, after recrystallization and sublimation, m. 149-50°, did not depress the m. p. of II prepared by KMnO4 oxidation of 5-chloro-2-acetylthiophene. Similarly 1.9 g. I (0.015 mole) and 0.037 mole NaOCl gave 0.4 g. (14%) 4,5-dichloro-2-thiophenecarboxylic acid, m. 194-4.5° (from H2O) (cf. m.p. 196-7° of Steinkopf and Kohler in C.A. 32, 3391.1). Oily by-products from several runs were combined to give a considerable fraction of 2,5-dichlorothiophene (III), b. 160-5°, nD16 1.5624; 3,4-dinitro derivative m. 85-5.5°. The by-product oil from a mixture of I and 3 moles NaOCl was a mixture of chlorinated thiophenes, with III the principal constituent.
Journal of the American Chemical Society published new progress about Chlorination. 31166-29-7 belongs to class chlorides-buliding-blocks, and the molecular formula is C5H2Cl2O2S, COA of Formula: C5H2Cl2O2S.
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics