Selective cycloaddition of ethylene oxide to CO2 within the confined space of an amino acid-based metal–organic framework

Abstract

Host–guest chemistry within the confined space of metal–organic frameworks (MOFs) offers an almost unlimited myriad of possibilities, hardly accessible with other materials. Here we report the synthesis and physical characterization, with atomic resolution by single-crystal X-ray diffraction, of a novel water-stable tridimensional MOF, derived from the amino acid S-methyl-L-cysteine, {SrZn₆[(S,S)-Mecysmox]₃(OH)₂(H₂O)}·9H₂O (1), and its application as a robust and efficient solid catalyst for the cycloaddition reaction of ethylene/propylene oxide with CO₂ to afford ethylene/propylene carbonate with yields of up to 95% and selectivity of up to 100%. These results nicely illustrate the great potential of MOFs to be game changers for the selective synthesis of industrially relevant products, representing a powerful alternative to the current heterogeneous catalysts.