A simple approach to bis-spirocycles and spiroindole derivatives via green methods such as Fischer indolization, ring-closing metathesis, and Suzuki--Miyaura cross-coupling

Abstract

We have developed a simple synthetic methodology for bis-spirocycles and spiroindole derivatives starting with a commercially available 6-bromo-2-tetralone. Here, we have used Fischer indolization, ring-closing metathesis, and Suzuki--Miyaura cross-coupling as key steps to assemble a variety of spirocyclic frameworks. The methodology developed here is simple and it may be useful to prepare various spirocycles containing indole moiety.