Hypercrosslinked porous polyporphyrin by metal-free protocol: characterization, uptake performance, and heterogeneous catalysis

Abstract

Through metal-free protocol, hypercrosslinked porous polyporphyrin with permanent porosity was obatined via the Friedel–Crafts alkylation of tetracarbazolylporphyrin using formaldehyde dimethyl acetal as an external cross-linker. Its chemical structure and porosity was well characterized and confirmed. The BET specific surface area value of HCP-TCPP is 1050 m2 g−1 and related dominant pore size is centered at 0.63 nm. The adsorption amount of methanol by HCP-TCPP is high up to 800 mg g−1 (about 25.0 mmol g−1) at its saturated vapor pressure, which is higher than that of toluene (600 mg g−1, 6.5 mmol g−1). Further study indicates that polymer HCP-TCPP, possessing the high BET specific surface area and total pore volume, exhibits good hydrogen uptake of 3.44 wt % (77 K) and high carbon dioxide uptake of 41.1 wt % (298 K) at 18.0 bar. Besides, the obtained porous polymer can also be used as an effective heterogeneous catalyst for the Knoevenagel condensation between various aldehydes and malononitrile.

Direct Heterogenization of Salphen Coordination Complexes to Porous Organic Polymers: Catalysts for Ring-Expansion Carbonylation of Epoxides

“…The polymers exhibited typical type I and type IV isotherms (according to the IUPAC classification of adsorption isotherms), as shown in Figure S5. 48,49 The uptake of N 2 in the relative pressure range of >0.1 can be ascribed to the mesoporous nature; the desorption branch of the isotherm did not close to the adsorption branch, and such hysteresis loop behavior displayed by POP 2 is similar to that of reported mesoporous systems in which the adsorption steps arise through smaller micropore channels or the swellable highly disordered polymer structure in the material, 50,51 where the evacuation of the polymeric material is hindered by the smaller exit vacancies. 52,53 A weak uptake of N 2 at a low relative pressure (P/P 0 = 0−0.1) may be attributed to the microporous nature of the POP 5, while the hysteresis loop over the whole range of relative pressure can be ascribed to mesoporosity.…”

“…58,60 The peak at 67.5 ppm corresponds to methylene carbon bound to an oxygen atom, which results from the incomplete reaction of FDA. 48 The comparative study of the FTIR spectra of salphen ligands, monomeric complexes, and porous polymers was conducted to understand the structure of the formed polymers, shown in Figure 2b for 2 (Figure S12b for 5). Weak bands appearing in the region of 3002−2868 cm −1 can be assigned to C−H stretching modes for the phenyl functional groups of salphen complexes 1 and 4 and polymers 2 and 5, along with the newly formed methylene cross-linking bridges.…”

Highly Porous Hypercrosslinked Polymers Derived from Biobased Molecules

“…Assuming regular hexagons, this would correspond to ad istribution of CÀCb ond lengthsc entered at approximately 0.133 nm, which is on the short end of the range of 0.133-0.142 nm that is typicallys een for graphene-like or graphitic sheets,. [93][94][95][96] The features of the particles could have been relatedt ot he insolubility of the developing polymer networks during synthesis, whereby the phase-separated polymer formed small drops to minimize the polymer/solvent interface. The particles were smallerf or pQ (Figure 6a)t han for pD (Figure 6b).…”

“…Similar data on morphologies of other types of HCPs and other porous organic sorbents have been observed. [93][94][95][96] The features of the particles could have been relatedt ot he insolubility of the developing polymer networks during synthesis, whereby the phase-separated polymer formed small drops to minimize the polymer/solvent interface. Speculatively, the growing polymer networks might have been interconnected to other networks, hindered the formation of perfect spheres, and insteadf ormed the network of particles seen in Figure 6.…”

Pyrrole-Based Conjugated Microporous Polymers as Efficient Heterogeneous Catalysts for Knoevenagel Condensation

“…In addition, CMPs could also function as catalysts for various chemical transformations, e.g. CO 2 reduction reaction ( Hou et al, 2020 ), water splitting for hydrogen production ( Zhao et al, 2018 ), erobic oxidations ( Jiang et al, 2020 ), a-alkylation of aldehydes ( Luo et al, 2015 ), Knoevenagel condensation ( Feng et al, 2017 ) and singlet oxygen generation ( Zhang et al, 2013 ). However, the cost-effective CMP based heterogeneous catalysts with excellent catalytic performances is still very rare.…”