Batch and Flow Synthesis of Pyrrolo[1,2-a]-quinolines via an Allene-Based Reaction Cascade

J Org Chem. 2015 Nov 6;80(21):10806-16. doi: 10.1021/acs.joc.5b01982. Epub 2015 Oct 28.

Abstract

An efficient reaction cascade delivering a series of pyrrolo[1,2-a]quinolines bearing phosphonate or phosphine oxide moieties is presented. This sequence exploits the in situ transformation of propargylic alcohols into transient allenes by means of a strategic [2,3]-sigmatropic rearrangement followed by trapping of the resulting allenes by an adjacent pyrrole ring. Furthermore, the initial small scale batch process was successfully translated into a continuous flow process allowing efficient preparation of selected pyrrolo[1,2-a]quinolines on multigram scale without any safety concerns due to the reaction's inherent exothermic profile.

Publication types

  • Research Support, Non-U.S. Gov't