Chemical Consequences of the Mechanical Bond: A Tandem Active Template-Rearrangement Reaction

Angew Chem Int Ed Engl. 2019 Mar 18;58(12):3875-3879. doi: 10.1002/anie.201813950. Epub 2019 Feb 14.

Abstract

We report the unexpected discovery of a tandem active template CuAAC-rearrangement process, in which N2 is extruded on the way to the 1,2,3-triazole product to give instead acrylamide rotaxanes. Mechanistic investigations suggest this process is dictated by the mechanical bond, which stabilizes the CuI -triazolide intermediate of the CuAAC reaction and diverts it down the rearrangement pathway; when no mechanical bond is formed, the CuAAC product is isolated.

Keywords: mechanical bonds; rearrangement; rotaxanes; supramolecular chemistry; triazoles.