Zirconium (IV) porphyrin graphene oxide: a new and efficient catalyst for the synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones

Abstract

A covalently cross‐linked graphene oxide (GO) as a catalyst was prepared by a cross‐linking process using the nucleophilic reaction of zirconium (IV)‐coordinated 5,10,15,20‐tetrakis (aminophenyl)porphyrin (ZrPPh) with carboxyl groups of the edges of GO (GO‐ZrPPh). The chemical structure of catalyst was characterized by different analyses such as FT‐IR, SEM, TEM, EDS, ICP, TGA and UV. All analyses confirm the occurrence of successfully covalent immobilization of ZrPPh on the GO. Also, TEM and SEM images show that ZrPPh has been immobilized in the both of the edges and the basal plane of GO. The activity of the catalyst was studied for the synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones via Biginelli reaction. The cross‐linked catalyst is able to catalyze the reaction in short reaction times and good to excellent yields.

Recent advancements in organic synthesis catalyzed by graphene oxide metal composites as heterogeneous nanocatalysts

“…Ghadamyari et al [ 153 ] reported synthesis of dihydropyrimidin‐(1 H )‐ones via one‐pot three‐component condensation reaction of ethyl acetoacetate, various aldehydes, and urea in the presence of zirconium (IV) porphyrin GO (GOZrPPh) as a catalyst without any solvent at 70°C for 180 min (Scheme 23). To optimize the reaction conditions, 0.28 mol% of catalyst was selected for this reaction.…”

Air‐stable zirconium (IV)‐salophen perfluorooctanesulfonate as a highly efficient and reusable catalyst for the synthesis of 3,4‐dihydropyrimidin‐2‐(1H)‐ones/thiones under solvent‐free conditions

“…In show the merit of the present study, the results of using complex 1 for the synthesis of product 5a by reacting benzaldehyde, ethyl acetoacetate, and urea with other homogeneous and heterogeneous catalysts were compared ( Table 4, entries [3][4][5][6][7][8][9][10][11][12][13][14]. According to the obtained results [7,9,13,24,27,[31][32][33][53][54][55] our catalyst shows better catalytic activity with a shorter reaction time using solvent-free conditions with good recyclability. Apparently, the long fluoroalkyl chain in the sulfonate must be responsible for the hydrophobicity and increasing the catalytic activity.…”

“…Generally, dihydropyrimidinones are synthesized by the three‐component Biginelli reaction of aldehyde, 1,3‐dicarbonyl compound and urea, and much work on improving these protocols towards reaching milder reaction conditions and higher yields has been actively pursued. Until now, various catalysts and catalytic systems have been developed, including BF 3 ·OEt 2 , ZrCl 4 or ZrOCl 2 , InCl 3 , InBr 3 , YCl 3 , TaBr 5 , VCl 3 , metal triflates (Y, Sr, In, Cu), Fe (OTs) 3 · 6H 2 O, Mn (OAC) 3 · 2H 2 O, Y (NO 3 ) 3 · 6H 2 O, H 3 BO 3 , PPh 3 , Cp 2 Ti‐based Lewis acids, TBAB, Ag 3 PW 12 O 40 , SiO 2 ‐Cl, Fe 3 O 4 /PAA‐SO 3 H, nanomagnetic supported sulfonic acid, FeCl 3 ‐supported nanoporous silica, precious metals (Pt, Pd, Ru) on graphene oxide nanoparticle catalyst, zirconium porphyrin graphene oxide, H 3 PW 12 O 40 supported on ZIF‐9(NH 2 ), Cu@SBA‐15, and others . However, these catalysts of the Biginelli reaction procedures are associated with harsh reaction conditions, expensive and corrosive reagents, the use of volatile organic solvents, poor substrate generality, unsatisfactory yields, longer reaction times and poor catalyst recyclability.…”

Copper and nickel immobilized on cytosine@MCM‐41: as highly efficient, reusable and organic–inorganic hybrid nanocatalysts for the homoselective synthesis of tetrazoles and pyranopyrazoles

“…[1][2][3][4][5][6][7] Therefore, nanoparticles have been widely used as solid supports for the immobilization of homogeneous catalysts. [8][9][10] For example, silica materials, [11] polymers, [12] graphene oxide, [13][14][15][16] carbon nanotubes, [17] iron oxide, [18] ionic liquids, [19,20] boehmite nanoparticles, [21,22] biochar, [23] magnetic nanoparticles, [24][25][26] etc. were employed as support for the stabilization of homogeneous catalysts.…”