An interpenetrating amine-functionalized metal-organic framework as an efficient and reusable catalyst for the selective synthesis of tetrahydro-chromenes

摘要

The amine group of the 2-amino-1,4-benzenedicarboxylic acid (NH2-BDC) ligand in a novel two-fold interpenetrated metal-organic framework, [Zn(NH2-BDC)(4-bpdb)]center dot 2DMF(TMU-17-NH2) has been found to be a base catalyst active site. TMU-17-NH2 consists of both NH2-BDC and the N, N'-bipyridine-type rigid linkers (4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-2,3-butadiene) with ZnN2O4 secondary building units (SBUs). The MOF was characterized by FT-IR spectroscopy, elemental analysis, powder X-ray diffraction, thermal gravimetric analysis and single-crystal X-ray diffraction. The amine-functionalized framework was used as an efficient heterogeneous base catalyst for the synthesis of tetrahydro-chromenes. Excellent conversions were obtained under mild conditions in the presence of 6 mol% catalyst. The TMU-17-NH2 catalyst could be reused several times without significant degradation in catalytic activity.