Highly efficient construction of spirocyclic chromanone–pyrrolidinesviaCu(i)/TF–BiphamPhos-catalyzed asymmetric 1,3-dipolar cycloaddition†
Abstract
A facile synthesis of highly functional spiro-[4-chromanone-3,3′-pyrrolidine] bearing one unique spiro quarternary and three tertiary stereogenic centers is developed in excellent stereoselectivity for the first time.