Green and Efficient Synthesis of Spiroheterocyclic Compounds from Reactions of Isatins, 3-Amino-1-phenyl-1<i>H</i>-pyrazol-5(4<i>H</i>)-one, and Monocyclic Ketones

The reactions of isatins, 3-amino-1-pheyl-1H-pyrazol-5(4H)-one, and monocyclic ketones, have been developed for preparation spiro[indoline-3,4'-pyrazolo[3,4-b]quinoline]-2,3'(6'H)-dione, spiro[cyclohepta[b]pyrazolo[4,3-e]pyridine-4,3'-indoline]-2′,3-dione, spiro[cycloocta[b]pyrazolo[4,3-e]pyridine-4,3'-indoline]-2′,3(6H)-dione, spiro[cyclo dodeca[b]pyrazolo[4,3-e]pyridine-4,3'-indoline]-2′,3(6H)-dione derivatives in aqueous acetic acid mixed medium. Studies shown that water was an excellent medium this reaction. significant features method are wide substrate scope, high yields, operational simplicity, minimal environment impact.