Epoxidation of alkenes with molecular oxygen catalyzed by a manganese porphyrin-based metal-organic framework

The flexible nature of reticular assemblies and high specific surfaces of metal-organic frameworks (MOFs) offers new opportunities for the design of heterogeneous catalysts capable of industrially relevant reactions. We demonstrate the first instance of alkene epoxidation at mild conditions using molecular oxygen by a manganese porphyrin containing MOF, MOF-525-Mn [Zr6O4(OH)(4)(MgC48H24O8N4Cl)(3)]. This zirconium MOF with a manganese porphyrin catalyst shows minimal deactivation over long periods and maintains its structure and high activity after multiple catalytic cycles. Kinetic studies of styrene epoxidation are in agreement with theoretical and experimental studies of homogeneous reactions with the same porphyrin unit, suggesting that the heterogeneous catalyst operates according to a similar mechanism as its homogeneous counterpart. (C) 2014 Elsevier B.V. All rights reserved.