Highly Efficient Organic and Macromolecular Synthesis Using Sequential Copper Catalyzed Azide-Alkyne 3+2 Cycloaddition and ATRA/ATRP

摘要

Catalyst regeneration technique in transition metal-mediated atom transfer radical polymerization (ATRP), addition (ATRA) and cyclization (ATRC) reactions utilizes environmentally benign reducing agents, which continuously regenerate transition metal complex in the lower oxidation state (activator) from the higher oxidation state (deactivator). This technique has been very successful in reducing the catalyst loadings from several thousands to 5-100 ppm levels. Consequently, this methodology has attracted further academic interest and its scope has been expanded to include sequential organic transformations such as ATRA/ATRC and ATRA/cyclopropanation. Additionally, copper-catalyzed azide-alkyne [3+2] cycloaddition (CuAAC) has been widely explored in combination with ATRP to generate a plethora of macromolecular structures. This chapter focuses on recent advances in small molecule synthesis using CuAAC and ATRA to form functionalized triazoles and polytriazoles.