Fe(ii)–organic frameworks as heterogeneous catalysts for achieving diverse CO2 conversions

Abstract

The design and construction of efficient, low-cost, eco-friendly noble-metal-free metal–organic framework (MOF) catalysts for CO₂ conversion under mild conditions are appealing for green and sustainable chemistry but remain extremely challenging. Herein, two new two-dimensional (2D) Fe^II-MOFs (1 and 2) were successfully synthesized. MOF 1 could be used as a heterogeneous catalyst for achieving three diverse CO₂ conversions: (1) carboxylation reaction of terminal alkynes with CO₂; (2) cycloaddition reaction of epoxides with CO₂; and (3) carboxylative cyclization of propargylic amines with CO₂. In these three diverse conversions, MOF 1 not only exhibited excellent catalytic activity and substrate tolerance and exceptionally high yield but also showed high recyclability and repeatability, exhibiting excellent catalytic activity after ten cycles. Furthermore, the mechanisms of the three reaction types were discussed in detail. This work provides a strategy for the conversion of CO₂ into a variety of high value-added chemicals.