Microwave-Assisted Synthesis of Near-Infrared Fluorescent Indole-Based Squaraines

Org Lett. 2015 Jul 2;17(13):3306-9. doi: 10.1021/acs.orglett.5b01453. Epub 2015 Jun 22.

Abstract

A microwave-assisted method for the preparation of a wide color range of 2,3,3-trimethylindolenine-based squaraines and their intermediates is described. This practical approach allows the rapid preparation of both symmetrical and nonsymmetrical squaraine dyes, reducing reaction time from days to minutes with more than 2-fold improvement in product yields when compared to conventional methods.