On Water: Diastereoselective Synthesis of Functionalized 3‐Nitrodihydroquinolin‐4(1H)‐ones under Catalyst‐free conditions

Herein we describe an uncatalyzed and eco‐friendly methodology for the diastereoselective synthesis of 3‐nitro dihydroquinolin‐4(1H)‐ones through an imine formation‐cyclization reaction on water medium. Water is an essential medium to effect this reaction efficiently without any catalyst. In addition, the synthesis of deuterium labelled 3‐nitrodihydroquinolin‐4(1H)‐ones has been accomplished using this protocol. The key characteristics of this approach include catalyst free, scalable, mild reaction condition, easy isolation, and greenest solvent medium.