Functionalization of a Pyridine Framework through Intramolecular Reissert-Henze Reaction of N-(Carbamoyloxy)pyridinium Salts and Unexpected Insertion of Ethereal Solvents

摘要

A new strategy for synthesis of the 2-pyridyl carbamates is reported. This strategy exploits a new intramolecular transformation of an acyloxy group from N-carbamoyloxypyridinium salts (Reissert-Henze-type reaction) as the key step. Addition of a silver salt effectively accelerates the intramolecular attack of the carbonyl oxygen at the 2-position of the pyridine ring. Additionally, a new rearrangement of the acyloxy group, combined with insertion of an ethereal solvent to give pyridine derivatives having a coordinating tether, is reported.