Metal-free coupling of saturated heterocyclic sulfonylhydrazones with boronic acids

The coupling of aromatic moieties with saturated heterocyclic partners is currently an area of significant interest for the pharmaceutical industry. Herein, we present a procedure for the metal-free coupling of 4-, 5-, and 6-membered saturated heterocyclic p-methoxyphenyl (PMP) sulfonylhydrazones with aryl and heteroaromatic boronic acids. This procedure enables a simple, two-step synthesis of a range of functionalized sp2−sp3 linked bicyclic building blocks, including oxetanes, piperidines, and azetidines, from their parent ketones. ■ INTRODUCTION