Base-Promoted Tandem Synthesis of Indolo[1,2-b]isoquinolines from 2-Alkynylaniline and Nitroarenes

Polycyclic fused indoles have many applications in medicinal chemistry. Using 2-alkynylanilines, KN(SiMe3)2, and nitroarenes, a tandem method for the synthesis of various indolo[1,2-b]isoquinolines is presented (53 examples, yields up to 88%). A key feature of this strategy is the construction of fused indole and isoquinoline heterocycles with the generation of three new bonds in one pot. In addition, nitroarenes are used as electrophiles to install N-aryl moieties.