An efficient, sustainable approach to the chemo and regioselective synthesis of novel spiroindenoquinoxaline grafted piperidone hybrid heterocycles

Abstract

An efficient, eco-friendly and sustainable approach for the synthesis of novel spiroindeno[1,2-b]quinoxaline-3-phenylspiro[4,3″]benzylidenepiperidone ring system has been developed by a one-pot four component [3 + 2] cycloaddition strategy. The 1,3-dipole generated in situ from quinoxalinone and l-phenylalanine reacts with the highly functionalized dipolarophiles, bisarylidene piperidones affording spirohybrid heterocycles in good yields. The unexplored novel class of dispirohybrid heterocycles obtained possess three CN and two CC bonds with four adjacent stereogenic carbons, out of which two is spirocarbons. The structure of compounds was elucidated using 1H, 13C and mass spectroscopic studies.

Keywords

• Azomethine ylide
• Spiroindenoquinoxalinone
• Spiropyrrolidines
• Benzylidene piperidone
• Ionic liquids