One‐Pot Sequential [3+2] Cycloaddition and Ring‐Expansion Reaction for Selective Synthesis of Polycyclic Spirooxindole

Abstract

The one-pot three-component reaction of L-proline, isatins and 1-(2-hydroxyphenyl)-3-phenylprop-2-en-1-ones and sequential reaction with methyl propiolate in refluxing methanol resulted in novel functionalized spiro[chromane-2,3'-indoline]-2',4-diones as major products and spiro[chromeno[3,2-d]azocine-2,3'indolin]-3-yl)acrylate as minor products. On the other hand, the similar one-pot-three-component reaction of L-proline, isatins and 3-(2-hydroxyphenyl)-1-phenylprop-2-en-1-ones and sequential reaction with methyl propiolate in refluxing acetonitrile predominately afforded the unique 6b,14-(epoxy[1,2]benzeno)pyrrolo[1',2':1,2]azocino[4,5-c]quinoline-8carboxylates in satisfactory yields.