ABOUT REACTIONS OF α-BROMOMETHYLACRYLATE AND α-BROMOSTYRENE WITH 2-ME- THOXYCARBONYL BENZENEDIAZONIUM BROMIDE
3-bromo-3,4-dihydroisocoumarin-3-carboxylate has been obtained by the reaction of α-bromoacrylate with 2-methoxycarbonyl benzenediazonium bromide in the presence of CuBr as a catalyst. It has been found that methyl isocoumarin-3-carboxylate can be easy obtained from 3-bromo-3,4-dihydroisocoumarin-3-carboxylate by the dehydrobromination reaction. When using α-bromostyrene in this reaction cyclization does not occurred, only 2-aryl-1-phenylethanones are isolated.