A novel synthesis of oxazino derivatives from an efficient one-pot threecomponent reaction of isoquinoline and dimethylacetylene dicarboxylate (DMAD) in the presence of arylaldehyde derivatives

The 1,4-dipolar derived from isoquinoline and DMAD has been shown to react readily with arylaldehyde derivatives in the diastereoselective synthesis of (2S,2R)-dimethyl-2,11b-dihydro-2-(3-nitrophenyl)-[1,3]-oxazino-[2,3-a]-isoquinoline-3,4-dicarboxylate (4a), dimethyl-2-(4-bromophenyl)-2,11b-dihydro-[1,3]-oxazino[2,3-a]-isoquinoline-3,4-dicarboxylate (4b), dimethyl-2-(furan-2-yl)-2,11b-dihydro-[1,3]oxazino[3,2-a] isoquinoline-3,4-dicarboxylate (4c) and dimethyl-2,11b-dihydro-2-(5-nitrofuran-2-yl)-[1,3]-oxazino-[2,3-a]-isoquinoline-3,4-dicarboxylate (4d) in the moderate to good yield. The reaction was carried out in the room temperature or solvent free in microwave.