Isoreticular Nonmetal−Organic Frameworks (N-MOFs) as Catalysts for Organic Reactions

Abstract

The recent discovery of isoreticular nonmetal−organic frameworks (N-MOFs), composed by protonated amines and free triazine functionalities, has brought a new kind of solid materials with potential application in catalysis. However, to our knowledge, N-MOFs have not been reported yet as catalysts for any organic reaction. Here we show that two representative N-MOFs not only catalyze different organic reactions but also proceed in cascade on the basis of a bifunctional acid/base mechanism. Acetal deprotection can be coupled with either the Knoevenagel condensation or the Biginelli reaction to occur in good yields as a function of the N-MOF pore size—i.e., the wider the pore is, the higher is the catalytic activity—showcasing the key role of the isoreticular organization of the material. The N-MOF is recyclable, providing a new simple and organic solid for heterogeneous catalysis.