PdO nanoparticles supported on triazole functionalized porous triazine polymer as an efficient heterogeneous catalyst for carbonylation of aryl halides

Abstract

A well-defined triazole functionalized porous triazine based polymers act as solid heterogeneous catalyst after incorporating palladium oxide nanoparticles (PdO@TTAS) have been synthesized and thoroughly characterized by various techniques such as, FT-IR, UV-DRS, solid state 13 C CP-MAS, XPS, powder Xray diffraction, TGA, SEM and TEM analysis has been detailed illustrated. It is important to note that synthesized catalytic performance for carbonylation of aryl halides (X = I, Br) with EDC.HCl (N-(3-dimethylaminopropyl)-N′ethylcarbodiimide hydrochloride), and formic acid was found to be an effective CO source in the presence of triethylamine as a base and DMF as a solvent medium at 80°C for about 3 hr. The PdO@TTAS catalyst exhibits superior catalytic performance and along with good yield (up to 90%). Moreover, studying the heterogeneity and reusability of the environmentally friendly solid catalyst can be easily separated by simple filtration and then recycled for several times.In this reaction method, we avoided ligand, additive, promoters and CO gas, due to additional problem arise by using gaseous CO, highly toxic greenhouse gases and high pressurized reaction setup.

Mesoporous Polymeric Cyanamide‐Triazole‐Heptazine Photocatalysts for Highly‐Efficient Water Splitting

“…[ 18 ] Another new peak at 111.9 ppm can be clearly observed for THP and CTHP 30 , which can be assigned to the HNC(H)N (4) in the triazole group. [ 19 ] These results further indicate that the polymerization of urea and 3‐AT into heptazine‐based carbon nitrides with cyanamide and triazole groups with controllable morphologies.…”

“…[ 7b ] The optical absorption of THP exhibited a strong redshift in the intrinsic absorption edge to 485 nm and increased band tailing to 675 nm due to the introduction of triazole groups, as the conjugated heterocyclic ring systems have not only n–π* electronic transitions but also π–π* transitions originating from the sp 2 hybridization of C and N in the triazole clusters. [ 19 ] The bandgaps of CHP and THP were 2.71 and 1.91 eV, respectively. Due to the synergistic effects of the cyanamide and triazole groups, CTHP 30 exhibited an obvious redshift in its absorption spectrum, with an absorption edge at 478 nm corresponding to a bandgap of 2.65 eV (inset of Figure 3a).…”

1,2,3-Triazole framework: a strategic structure for C–H⋯X hydrogen bonding and practical design of an effective Pd-catalyst for carbonylation and carbon–carbon bond formation

“…36,39,[51][52][53][54] Most of the reported formic acid-assisted formylation reactions have been performed under homogeneous catalytic conditions; meanwhile, some researchers have recently directed their studies toward the use of heterogeneous Pd-catalysts for CO gas free formylation reactions. 55,56 Based on our results and the other reports 52,54 we have proposed a detailed mechanism for formic acid-assisted formylation reaction of aryl halides using Pd@click-MNPs/CS catalyst, in which the carbon monoxide molecule is formed in situ from the reaction of formic acid with DCC activator (Scheme 4). According to this mechanistic model, the free CO generated in the reaction media interacts with palladiumcatalyst and forms an acyl-Pd intermediate in the catalytic cycle, next, followed by decarboxylation process and the reductive elimination reaction, the desired product is obtained.…”

Recent advances in the design, synthesis and catalytic applications of triazine-based covalent organic polymers

“…16a). 128 This newly synthesized catalyst was fully characterized and employed for the carbonylation of aryl halides using formic acid (Fig. 16b).…”

“…Fig.16(a) Synthesis scheme of Pd@TTAS; (b) Pd@TTAS catalyzed formylation reaction 128. (Reproduced from ref 128. with permission from the John Wiley and Sons.…”