Condensation of 2-hydroxyacetophenones with trichloroacetonitrile as a route to 2-trichloromethylchromones and 4-hydroxycoumarins

Condensation of 2-hydroxyacetophenones with trichloroacetonitrile in the presence ofN-methylanilinomagnesium bromide affords hydroxyaryl β-amino-β-trichloromethylvinyl ketones, which are converted into 2-trichloromethylchromones upon treatment with concentrated HCl. The resulting compounds react with alcoholic solutions of NH₃ or KOH to form 3-amino-1-(2-hydroxyaryl)-4,4,4-trichlorobut-2-en-1-ones and 4-hydroxycoumarins, respectively. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 476–479, March, 2000.