De Novo Access to SO₃H-Grafted Porous Organic Polymers (POPs@H): Synthesis of Diarylbenzopyrans/Naphthopyrans and Triazoles by Heterogeneous Catalytic Cyclocondensation and Cycloaddition Reactions

Abstract

All the reagents employed were available from commercial sources and were used without further purification. Freshly distilled solvents were used for the synthesis. Column chromatography was performed using silica gel of 100-200μ mesh. 1 H and 13 C NMR spectra were recorded on JEOL-Lambda spectrometers. IR spectra were recorded on a Bruker Vector 22 FT-IR spectrometer. Melting points were measured using a JSGW melting point apparatus. High-resolution mass spectra (HRMS) were recorded on a Waters ESI-QTOF machine. Thermogravimetric analyses were carried out with a SDT-Q600TGA apparatus under N2 atmosphere with a heating rate of 10 °C/min. SEM images were recorded on a Nova Nano SEM 450 FE-SEM scanning electron microscope. TEM images were recorded on a carbon-coated Cu grid on a Bruker Nano GmbH HRTEM. XPS analyses were carried out on an X-ray photoelectron spectroscopy module (PHI 5000 Versa Prob II, FEI Inc.). Elemental analyses were performed with vario MICRO Element Analyzer. The gas adsorption and desorption studies were performed using a Quantachrome AutosorbiQ automated gas sorption analyzer. The average pore size and average pore distributions were calculated NLDFT methods using the N2 sorption isotherms. The substituted propargyl alcohols, i.e., 1-(4-(tert-butyldimethylsilyloxy)phenyl)-1-phenylprop-2-yn-1-ol, 1 3-(tert-butyldimethylsilyloxy)-9-ethynyl-9H-fluoren-9-ol, 1 1,1-bis(4-(tertbutyldimethylsilyloxy)phenyl)prop-2-yn-1-ol, 1 1,1-bis(4-methoxyphenyl)prop-2-yn-1-ol 2 and 9ethynyl-9H-fluoren-9-ol, 2 were synthesized according to reported procedures. S3 Scheme S1. Synthesis of 2,2',6,6'-Tetramethylbiphenyl (MeM) 3 A two-necked round-bottomed flask was charged with magnesium turnings (0.2 g, 8.1 mmol), 30 mL of dry THF and 0.1 mL of 1,2-dibromoethane under N2 atmosphere and stirred at rt for 15 min. Subsequently, 2-bromo-m-xylene (1.0 g, 5.4 mmol) was added over a period of 15 min and the reaction mixture was stirred at rt for further 1.5 h. At the end of this period, the resultant Grignard reagent was added slowly to a suspension of FeCl3 (1.31 g, 8.1 mmol) in dry THF (20 mL) taken in another round-bottom flask under N2 atmosphere at ice-cold conditions. After completion of the addition, the reaction mixture was allowed to attain rt and subsequently heated to reflux for 4 h. At the end of this period, the reaction mixture was carefully quenched with icecold water and the organic matter was extracted with CHCl3 (3 × 30 mL). The combined organic extract was dried over Na2SO4 and concentrated under reduced pressure. The pure product was obtained by silica gel column chromatography, yield 0.88 g (78%), 1 H NMR (CDCl3, 400 MHz) δ 1.94 (s, 12H), 7.14−7.19 (m, 6H). Scheme S2. Synthesis of 2,2',6,6'-Tetramethoxybiphenyl (OMeM) 4 To the mixture of 1,3-dimethoxybenzene (1.0 g, 7.24 mmol) and TMEDA (1.2 mL, 7.96 mmol) in dry THF (40 mL) at-78 °C was slowly added a solution of n-BuLi (1.6 M in hexane, 6.25 mL, 8.7 mmol) under N2 atmosphere. Subsequently, the reaction mixture was allowed to attain 0 °C and stirred at...

Synthesis of a Carbazole-Based Nanoporous Organic Polymer for Efficient Adsorption/Separation of C2H2 and CO2

“…The IAST selectivity of C 2 H 2 /CO 2 on CNOP-6, calculated to be 2.29 at 298 K and 100 kPa in a 50%:50% fraction, is comparable to those of numerous porous materials like JXNU-15 (2.39), UPC-200­(Al)-F-BIM (2.25), and FJU-36 (2.8) . The C 2 H 2 /CO 2 selectivity of 2.29 surpassed those of numerous previously reported porous materials, including MeBPs (1.5–1.7), [Ca­(dtztp) 0.5 (DMA)]·2H 2 O (1.7), and [Ni­(dpip)]·2.5DMF·H 2 O (1.9) . This demonstrates the excellent C 2 H 2 adsorption uptake and good C 2 H 2 /CO 2 selectivity of CNOP-6, indicating its potential for separating C 2 H 2 /CO 2 .…”

“…Moreover, CNOP-6 demonstrates an impressive C 2 H 2 adsorption performance of up to 114.9 and 80.2 cm 3 ·g –1 under 273 and 298 K at 100 kPa, respectively, equivalent to 5.13 and 3.58 mmol·g –1 . Notably, the C 2 H 2 uptake obtained with CNOP-6 at 298 K exceeds those of previously reported NOPs, as displayed in Table S1, like TpPa-NO 2 (63.73 cm 3 ·g –1 ), TFT-COF (39.4 cm 3 ·g –1 ), and MeBP (64.6 cm 3 ·g –1 ) . Except for its higher C 2 H 2 uptake, CNOP-6 also exhibits an exceptional CO 2 uptake of 55.4 cm 3 ·g –1 under ambient conditions, which is competitive with the previously reported NOPs, like CNOPs (46.5–53.4 cm 3 ·g –1 ) − and NUSs (10.3–11.2 cm 3 ·g –1 ) .…”

“…Notably, the C 2 H 2 uptake obtained with CNOP-6 at 298 K exceeds those of previously reported NOPs, as displayed in Table S1, like TpPa-NO 2 (63.73 cm 3 • g −1 ), 9 TFT-COF (39.4 cm 3 •g −1 ), 7 and MeBP (64.6 cm 3 •g −1 ). 6 Except for its higher C 2 H 2 uptake, CNOP-6 also exhibits an exceptional CO 2 uptake of 55.4 cm 3 •g −1 under ambient conditions, which is competitive with the previously reported NOPs, like CNOPs (46.5−53.4 cm 3 •g −1 ) 15−17 and NUSs (10.3−11.2 cm 3 •g −1 ). 10 The high C 2 H 2 and CO 2 adsorption capacities in CNOP-6 are likely attributed to its rich carbazole units, higher BET surface area, and abundant microporous structure.…”

“…Many studies have focused on the adsorption and separation of C 2 H 2 and CO 2 in NOPs. For example, Moorthy et al synthesized porous organic polymers using a 2,2′,6,6′-tetramethylbiphenyl core with α,α′-dichlorop-xylene, namely, MeBP and MeBP@H. These polymers showed a moderate C 2 H 2 uptake and a C 2 H 2 /CO 2 selectivity at 298 K. 6 Another study by Zhao et al developed two covalent−organic frameworks (COFs) using ellagic and triboronic acid-based building blocks. These COFs exhibited high C 2 H 2 adsorption uptake and excellent separation properties for C 2 H 2 /CO 2 mixtures thanks to the presence of abundant oxygen atoms in their specific pore chemistry.…”

Bottom-Up De Novo Synthesis of Porous Organic Polymers with Enone Functionalities as Supports for Pd and Cu Nanoparticles for Catalytic Tandem Synthesis

“…A wide variety of organic building blocks and a number of methodologies to synthesize POPs have been developed; some of the methodologies employed rely on the multistep synthesis and the use of heavy/transition metal-catalyzed reactions for polymerization, limiting their practical applications. , In our quest for the development of POPs in a cost-effective manner based on readily accessible starting compounds and facile synthetic transformations that preclude the use of metals, , we recently showed that the aldol condensation reaction can be diligently exploited for the construction of POPs . The polymers obtained by aldol condensation as the reaction for polymerization possess α,β-unsaturated carbonyl functionalities that can be exploited for the stabilization of Pd(0) nanoparticles similar to that of Pd(0) in tris­(dibenzylideneacetone)-dipalladium(0) (Pd 2 (dba) 3 ), a catalyst applicable to a number of organic transformations. , In an extension of our ongoing research that focuses on bottom-up development of POPs, we have expanded our initial investigations and designed and synthesized polymers ANT and NAP based on aldol condensation, cf.…”