SYNTHESIS OF 2-CARBETHOXY-3-METHYL-4-HYDROXYBENZOFURAN DERIVATIVES

Article abstract of DOI:10.1007/BF00475383

A number of 2-carbethoxy-3-methylbenzofuran derivatives were synthetized.A 5,5-gem-dibromo derivative was obtained in the bromination of 2-carbethoxy-3-methyl-4-oxo-4,5,6,7-tetrahydrobenzofuran.Dehydrobromination of this dibromo derivative gave 2-carbethoxy-3-methyl-4-hydroxy-5-bromobenzofuran.Depending on the structure of the starting compound and the brominating agent, the bromine in the bromination of 2-carbethoxy-3-methyl-4-hydroxy- and 4-acetoxybenzofurans with bromine and N-bromosuccinimide is incorporated either in the methyl group or in 5 and 7 positions of the benzofuran ring.The nitration of 2-carbethoxy-3-methyl-4-hydroxybenzofuran and its bromo derivative leads to 5-nitro- and 5,7-dinitrobenzofuran derivatives.The structures of the synthetized benzofuran derivatives were established by means of the PMR spectra.