Methyl 8- and 5-Nitro-1,4-Benzodioxane-2-Carboxylate

Abstract

2-Substituted 1,4-benzodioxanes bearing one or more substituents at benzene are important templates in the design and synthesis of a large variety of biologically active compounds. One of the most straightforward synthetic strategies to prepare them in racemic form and with a 2-substituent susceptible to further synthetically useful conversions is the condensation of commercially available methyl 2,3-dibromopropionate with already suitably functionalized catechol. Here, we obtain methyl 8- and 5-nitro-1,4-benzodioxane-2-carboxylate by reaction of methyl 2,3-dibromopropionate with 3-nitrocatechol. After separation, the two positional isomers could be unequivocally identified by HMBC NMR analysis.