Bisphosphonium salt catalyzed [3 + 2] annulation of N-tosylimino(iso)quinolinium ylides with aryl olefins under blue LED irradiation

Abstract

Bisphosphonium salt catalyzed [3 + 2] annulation of N-tosylimino(iso)quinolinium ylides with aryl olefins under visible light has been developed, providing a series of β-aryl-substituted pyrazolo(iso)quinoline compounds with good regioselectivity. During this research, a new oxygen-free approach was developed to improve the synthetic efficiency of the bisphosphonium catalyst.