The goals of green chemistry are to eliminate the production of hazardous materials during chemical synthesis and to improve the overall efficiency of chemical reactions. We are studying the bromination of indole-3-acetic acid (IAA) to 3-bromooxindole-3-acetic acid (BOAA), a reaction that suffers from poor atom economy and low percent yield. NMR analysis has revealed that IAA bromination is a two-step process. Poor regioselectivity in addition of the first equivalent of electrophilic bromine is the critical step, producing a mixture of oxindole products responsible for the poor overall reaction efficiency. We have found that oxindole-3-acetic acid (OAA) is the initial intermediate formed in the bromination of IAA, and this research was focused at optimizing the synthesis and isolation of OAA. Synthesis of OAA was accomplished using one equivalent of N-bromosuccinimide, and the products characterized using NMR spectrometry. We will report on how changing different reaction parameters effects the yield, atom economy and E-factor for OAA synthesis, including temperature, reaction time, stoichiometry, solvent, and the use of amides and amidines as Lewis base catalysts.

Applying green chemistry principles in the synthesis of oxindole-3-acetic acid: The initial intermediate in the bromination of indole-3-acetic acid to 3-bromoxindole-3-acetic acid

249th National Meeting (2015)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.