Fast and Robust Synthesis of Metalated PCN-222 and Their Catalytic Performance in Cycloaddition Reactions with CO₂

Abstract

A simple and quick setup for the synthesis of PCN-222 and of a variety of metalated PCN-222­(Co, Ni, Cu, and Zn), using of a microwave reactor, is reported for CO2 fixation. Metalation of prophyrins by microwave heating has been evaluated through UV–vis titration. PCN-222­(M) were obtained in a three-step, one-pot reaction in a remarkable 72% yield in only 30 min. The materials have been characterized using a variety of techniques. A study of CO2 fixation through cycloaddition with epoxides and azidirines using metalated PCNs as catalysts is described. Cyclic carbonates and oxazolidinones were formed using CO2 at atmospheric pressure under mild conditions. Higher activity was observed when PCN-222­(Co) was used compared to that with PCN-222­(Ni, Cu, Zn).

Recent progress in materials development for CO2conversion: issues and challenges

“…In addition, cobalt as a catalytic site displays remarkable performance compared to others such as Ni, Cu, Zn. 248 Again, ZIF-78 hexagonal prisms having the same length and thickness of 5 mm, were used in the synthesis of propylene carbonate (PC) from CO 2 and propylene oxide (PO). 249 Owing to dual functional sites of ZIF-78, i.e., Lewis acidic (Zn) and basic (-NH of imidazole linker) sites, the reaction takes place without the addition of any co-catalyst or solvent at 150 1C, 10 kg cm À2 pressure and 15 h of reaction time.…”

High yield room temperature conversion of carbon dioxide into cyclic carbonates catalyzed by mixed metal oxide (CuO‐ZnO) nano‐flakes/micro‐flakes (Cozi‐nmf)

“…[ 12 ] organic metal complexes, [ 13 ] organocatalysts, and quaternary ammonium. [ 14 ] Some of the known catalytic systems for epoxide–CO 2 coupling includes Al (III)@cages, [ 15 ] Ti (HPO 4 ) 2 ·H 2 O, [ 16 ] ZnCl 2 /Al 2 O 3 , [ 17 ] succinimide‐KI, [ 18 ] PCN‐222(Co), [ 19 ] PIM2, [ 20 ] and some complexes [ 21 ] of Zn, Co, Mo, Pd, Cr, Al, Cu, Mg, and Sn. Much of the catalytic systems reported to the cyclic carbonate synthesis are homogeneous catalysts.…”

Selective Synthesis of Imines by Photo-Oxidative Amine Cross-Condensation Catalyzed by PCN-222(Pd)

“…Different volumes of the titrating solution in the concentration range (0.28.6)•10 -3 M were added in a quartz cuvette containing 2 mL of 6.3•10 -6 M TCPP(H 2 ) and TCPP(Pd) and the corresponding UV-Vis spectra were acquired after each addition (Figure S2, a and b). As we previously reported, 1 porphyrins show two characteristic absorption bands, i.e. Soret, also known as B band, and Q bands.…”

“…The stoichiometric excess of 1:5 (TCPP(H 2 ):PdCl 2 ) during step i) was required to ensure a full metalation, aspect that was proved during this experiment (Figure S2, a). On the other hand, TCPP(Pd) (Figure S4, a) showed similar 1 H NMR signals and shifts that those corresponding to the TCPP(H 2 ) (Figure S4, b). However, the original signal at -2.94 ppm corresponding to the protons of the pyrrol (N-H) was not observed for TCPP(Pd), supporting the UV-Vis titration results.…”

“…The solid was dried in an oven at 100 ºC for 12 h. Yield TCPP(Pd): 291.1 mg (0.32 mmol, 93%). 1 H NMR (DMSO-d6 , 400 MHz): δ (ppm) = 13.27 (s, 4H), 8.79 (s, 8H), 8.36 (d, 3JHH = 8.3 Hz, 8 H), 8.27 (d, 3JHH = 8.3 Hz, 8 H). 13 C-NMR (DMSO-d6 , 100 MHz): δ (ppm) = 167.8, 145.4, 141.0, 134.5, 131.9, 131.0, 128.4, 121.5.…”