Nanoscale Mn^II-coordination polymers for cell imaging and heterogeneous catalysis

Abstract

A mixed ligand approach was exploited to synthesize a new series of Mn^II-based coordination polymers (CPs), namely, CP1 {[Mn(μ-dpa)(μ-4,4′-bp)]⋅MeOH}_∞, CP2 {[Mn₃ (μ-dpa)₃ (2,2′-bp)₃]}_∞, CP3 {[Mn₃(μ-dpa)₃(1,10-phen)₂]⋅2 H₂O}_∞, CP4 {[Mn(μ-dpa)(μ-4,4′-bpe)_1.5]⋅H₂O}_∞, CP5 {[Mn₂ (μ-dpa)₂ (μ-4,4′-bpe)₂]⋅1/2  DEF}_∞, and CP6 {[Mn(μ-dpa)(μ-4,4′-bpe)_1.5]⋅1/2DMA}_∞ (dpa=3,5-dicarboxyphenyl azide, 2,2′-bp=2,2′-bipyridine, 1,10-phen=1,10-phenanthroline, 4,4′-bpe=1,2-bis(4-pyridyl)ethylene, 4,4′-bp=4,4′-bipyridine, DEF=N,N-diethylformamide, DMA=N,N-dimethylacetamide), to develop multifunctional CPs. Various techniques, such as single-crystal X-ray diffraction (SXRD), FTIR spectroscopy, elemental analysis, and thermogravimetric analysis, were employed to fully characterize these CPs. The majority of the CPs displayed a four-connected sql topology, whereas CP4 and CP6 exhibited a two-dimensional SnS network architecture, which was further entangled in a polycatenation mode. Compound CP1 displayed an open framework structure. The CPs were scaled down to the nanoregime in a ball mill for cell imaging studies. Whereas CP2 and CP4 were employed for cell imaging with RAW264.7 cells, CP1 was exploited for both cell imaging and heterogeneous catalysis in a cyanosilylation reaction.