Three N–H Functionalized Metal–Organic Frameworks with Selective CO₂ Uptake, Dye Capture, and Catalysis

Abstract

Three N-H functionalized metal-organic frameworks, Pb-DDQ, Zn-DDQ, and Cu-DDQ, were synthesized with a new flexible dicarboxylate ligand based on quinoxaline (H2DDQ = N,N'-dibenzoic acid-2,3-diaminoquinoxaline). CO2 adsorptions indicate that Zn-DDQ and Cu-DDQ have greatly enhanced the CO2 uptake due to the opposite N-H groups on pyrazine. With very small adsorption of N2, Cu-DDQ shows high selectivity for CO2 and N2. The three MOFs also have large adsorptions of some selected dyes, while Zn-DDQ and Cu-DDQ with large but different shapes of pores are demonstrated to be promising materials for fast separation of MB/other and CV/other mixtures, respectively. The cyanosilylation of aldehydes and ketones with high yields in a short reaction time for Cu-DDQ indicates that Cu-DDQ has a higher Lewis acidity than the other two MOFs.

A new double layered 2-D copper(II) coordination polymer based on a semi-rigid ligand

“…The adjacent nets are connected by O-H···O hydrogen bonds ( figure 4(b)) between coordinated water O9 and uncoordinated carboxylate O, by which a 3-D supramolecular structure is formed. Consequently, the staggered layers afford a dense-packed structure, as shown in figure 3 [47]. Comparing with the reported Cu complex, 1 adopts different coordination and a diverse topological net.…”

Metal‐Organic Frameworks as Platform for Lewis‐Acid‐Catalyzed Organic Transformations

“…Several reports on MOF catalysed cyanosilylation reaction have appeared in the recent past, however, MOFs with copper metal node have rarely been used as a catalyst for the same reaction . Zhu et al . synthesized three MOFs with N‐H functionality, Pb‐DDQ ( 1 ), Zn‐DDQ ( 2 ), and Cu‐DDQ ( 3 ), with a flexible dicarboxylate ligand based on quinoxaline (H 2 DDQ= N , N ′‐dibenzoic acid‐ 2,3‐diaminoquinoxaline).…”

“…These are, for example, (i) pore size (ii) number of active sites (iii) dimensionality of MOF (iv) particle size (v) solvent conditions etc. Among the catalysts Pb‐DDQ ( 1 ), Zn‐DDQ ( 2 ), and Cu‐DDQ ( 3 ), Cu based MOF shows higher activity due to higher Lewis acidic nature of active sites which increase the percentage conversion to many folds . Similar comparison within CPO‐27‐M or MOF‐74‐M (M=Co, Mg, Mn, Ni, Zn) suggest that CPO‐27‐Mn ( 4 ) exhibits highest catalytic activity because of higher Lewis acidic nature of Mn‐active site .…”

Synthesis, Structure, and Dye Adsorption Properties of a Nickel(II) Coordination Layer Built from d-Camphorate and Bispyridyl Ligands

“…Thus, adsorption, with advantages of simplicity, efficiency, wide-ranging availability, and economic competitiveness, represents one of the most feasible treatment processes for dye removal from water [10,17]. The recent enthusiasm around the use of CPs and MOFs as advanced adsorbents for water purification has been documented in the past couple of years [7,11,12,[18][19][20][21][22][23].…”