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Information × Registration Number 0222U000927, 0120U100153 , R & D reports Title Development of new ways of obtaining substituted benzothiazoles, benzoxazoles, oxazolopyridines, thiazolopyridines, imidazopyrimidines and modification of their structures by transformation of functional groups popup.stage_title Head Tolkunov Sergej V., Доктор хімічних наук Registration Date 21-01-2022 Organization Institute of Physical and Organic Chemistry and Coal Chemistry. LM Litvinenko of the National Academy of Sciences of Ukraine popup.description2  Methods for preparation differently substituted derivatives of 2-mercaptobenzoxazoles by heating substituted ortho-aminophenols with sodium xanthate or with carbon disulfide in pyridine in the presence of organic bases - triethylamine. A large array of 2-mercaptobenzoxazoles containing halogens - chlorine, bromine, fluorine, 4,5,6-trifluoro - was synthesized; functional groups - amino, carboxyl, oxymethyl, formyl, sulfamide. Oxidation reactions of 2-mercapto [1,3] benzoxazoles with chlorine in the two-phase chloroform-hydrochloric acid system were studied. It is shown that 2-chloro [1,3] benzoxazoles are formed with high yields. A method for the preparation of substituted 2-chloro[1,3]benzoxazoles has been developed. The method gives high yields of 2-chlorine[1,3]benzoxazoles and high purity of products (90%). Nucleophilic substitution in 2-chlorobenzoxazoles has been studied. High activity of 2-chlorobenzoxazoles in reactions with primary and secondary amines is shown. A method for the preparation of substituted methyl 2-mercapto-1,3-benzoxazole carboxylates by cyclization of methyl 4-amino-3-hydroxybenzoate, methyl 3-amino-4-hydroxybenzoate, methyl 2-amino-3-hydroxybenzoate, methyl 3-amino-2-hydroxybenzoate with carbon disulfide in the presence of triethylamine has been developed. The action of chlorine on 2-mercapto[1,3]benzoxazoles in the two-phase chloroform-hydrochloric acid system synthesizes 2-chloro[1,3] benzoxazoles containing methyl carboxylate group in position 4-, 5-, 6-, 7-. Product Description popup.authors Bogza Sergii L. Smirnova Olga V. Tolkunov Andrey S. Tolkunov Valeriy S. Khyzhan Oleksandr I. popup.nrat_date 2022-03-09 Close