| 摘要 |
<p>A process for preparing a compound of formula (I) wherein R is C1-C6 alkyl, C3-C6 cycloalkyl or benzyl, and wherein the phenyl moiety of said benzyl group is optionally substituted by one or more substituents each independently selected from halo, nitro, C1-C6 alkyl, C1-C6 alkoxy, amino and trifluoromethyl, which comprises adding a solution comprising a compound of formula (II), a halonitromethane and an organic solvent selected from acetone, dimethylformamide, dimethylacetamide, acetonitrile, dimethylsulfoxide, N-methylpyrrolidinone and dimethoxyethane. In formula (II), wherein R is as defined above, to a mixture comprising a base and an organic solvent, said organic solvent being as defined above and the said base being selected from potassium carbonate, sodium carbonate, cesium carbonate, trisodium phosphate, and potassium fluoride, so that a compound of formula (I) is produced, any excess base being eliminated from the reaction mixture prior to recovery of the product (I).</p> |
