Development and Optimization of Methodology Towards Pyrrolic Frameworks

Abstract

This thesis focuses on the development and optimization of synthetic methodology towards pyrrolic frameworks. Two projects are discussed herein: the synthesis of azobispyrroles and attempts towards the synthesis of F-BODIPYs using a stoichiometric amount of dipyrrin and BF3‧OEt2 in a continuous flow operation. Chapter 2 explores the synthesis and optimization of the unreported group of azo dyes azobispyrroles using both the traditional approach via diazonium chemistry and through the reaction of a nitrobutanone with ammonium acetate in an acidic medium. Chapter 3 explores attempts towards the synthesis of F-BODIPYs using a stoichiometric amount of dipyrrin and BF3‧OEt2 in a continuous flow operation. The flow system aimed to avert the effects of the by-product fluoride which reacts with unreacted BF3‧OEt2 leading to the formation of the BF4ˉ anion, and consequently HBF4 dipyrrin salt, rather than enabling both free dipyrrin and BF3‧OEt2 to remain in solution for subsequent reaction. The use of inorganic bases as potential HF scavengers was also evaluated.