Regiocontrolled Coupling of Alkynes and Dipolar Reagents: Iron-Mediated [3+2] Cycloadditions Revisited

Cyclopentadienyliron dicarbonyl based allenyliron complexes were prepared, and their formal [3 + 2] cycloaddition with a number of dipolar reagents was investigated as a means of preparing heterocyclic compounds in a regiocontrolled manner. In addition, the mechanism of the isomerization of an allenyliron complex to its propargyliron tautomer was investigated. Results in support of both radical and two-electron mechanisms for isomerization are presented.

Automated summary

This study investigated the [3 + 2] cycloaddition reaction of allenyliron complexes as well as the mechanism of isomerization to propargyliron tautomer, presenting evidence for both radical and two-electron mechanisms.