Povarov-type Reaction of Anilines, Aqueous Acetaldehyde, and tBuONO for Access to N-Nitroso-1,2,3,4-tetrahydroquinolines.

Herein, we developed a novel multicomponent Povarov-type reaction of anilines, inexpensive and safe to handle aqueous acetaldehyde, and tert-butyl nitrite for the synthesis of N-nitroso-1,2,3,4-tetrahydroquinolines without the use of acids as catalyst and electron-rich alkenes as substrate. The reaction itself features excellent stereoselectivity, high functional group tolerance, a wide substrate scope, gram-scalability, operational simplicity, and mild conditions. In addition, the introduced N-nitroso group not only played a significant role in reaction efficiency but could be also utilized as a synthetically useful handle in organic synthesis. Moreover, the N-nitroso-1,2,3,4-tetrahydroquinoline products could be easily converted to a wide array of quinolines, by which our current method can be applied to the production of a promising herbicide candidate and Singulair as an anti-asthmatic drug.