Rh(III)-catalyzed cascade C–H activation/annulation/lactonization of quinoline-4-ols and alkynes has been reported. A broad range of tetracyclic pyrano[2,3,4-de]quinolines have been prepared in one-step with good functional group tolerance, excellent site selectivity, and high efficiency.
![Graphical abstract: Expeditious synthesis of pyrano[2,3,4-de]quinolines via Rh(iii)-catalyzed cascade C–H activation/annulation/lactonization of quinolin-4-ol with alkynes](http://hg.y866.cn/compound/lib/scimg/usr/1/C7CC04113F.jpg)