Concentrated solar radiation-assisted one-pot/multicomponent synthesis of pyranopyrazole derivatives under neat condition

Recent Synthesis of Mono‐ & Bis‐Pyranopyrazole Derivatives

“…Sajjadi et al (2023), for instance, reported on the synthesis of dihydropyrano[2,3c]pyrazoles via Knoevenagel-Michael multiple reactions by using green catalyst Fe 3 O 4 @gC 3 N 4 for the reaction of aldehydes, phenylhydrazine, ethyl acetoacetate and malononitrile under 1 h reflux to achieve 97 % yield of product (Route 1). [51] This reaction has also been reported by using numerous catalysts such as 1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium acetate ([DBU][Ac], [59] HMS/PrÀ Rh-Zr, [60] H 3 PO 4 /Al 2 O 3 , P 2 O 5 /SiO 2 , starch sulfuric acid, cellulose sulfuric acid, [61] thiourea dioxide (TUD), [62] PVCÀ EDAÀ CeIII, [63] citrus limon (lemon juice), [64] agave leaf ash extract, [65] piperidine, [66] sodium lactate, [67] NiWO 4 , [68] PBCMOamine, [69] CaO nanoparticles, [70] Fe 3 O 4 @chitosan-tannic acid bionanocomposite, [71] FSiPSS nano-catalyst, [72] nano ZrO 2 , [73] lactic acid : urea : NH 4 Cl, [74] H 4 [SiW 12 O 40 ], [75] NiFe 2 O 4 @SiO 2 À H 3 PW 12 O 40 (NFSÀ PWA), [76] Fe 3 O 4 @SiO 2 @CoSB, [77] PAN@melamine/Fe 3 O 4 nanocomposite, [78] isonicotinic acid, [79] nano-[Fe-PSMP]Cl 2 , [80] Fe 3 O 4 /MIP-202-H 4 WO 5 , [81] Zn(L-proline) 2 , [82] baker's yeast, [83] solar radiation, [84] Cu-DABP@Fe 3 O 4 /MCM-41, [85] Fe 3 O 4 @NFC@Co(II), [86] PdO/Al-SBA-15, [87] (MnCoFe 2 O 4 @Niacin-SO 3 H) + Cl À , [88] Zn-CA-MOFs [89] and Na 2 CaP 2 O 7 . [90] In 2022, Nguyen and coworkers reported different routes to the synthesis of pyrano[2,3-c]pyrazole derivatives, which involved a four-component reaction of benzyl alcohols, phenylhydrazine, ethyl acetoacetate and malononitrile with the aid of sulfonated amorphous carbon and eosin Y as c...…”

Green multicomponent synthesis of pyrano[2,3-c]pyrazole derivatives: current insights and future directions

“…These are also specic to certain reactions and geographical locations. 39,40 Yatin U. Gadkari et al, 41 showcased the utilization of concentrated solar radiation for the synthesis of pyranopyrazole derivatives. This involved a solvent-free and catalyst-free approach employing a multi-component strategy.…”

Guanidine Hydrochloride Catalyzed One‐Pot Multi‐Component Synthesis of Pyrazolopyranopyrimidine

“…All target compounds were characterized by their 1 H, 13 C NMR, and Mass spectra. 1 H and 13 C NMR spectra were obtained on a 400-MR NMR Spectrometer from Agilent Technologies using tetramethylsilane (TMS) as an internal standard and DMSO-d 6 as a solvent. For the nuclear magnetic resonance spectra interpretation, the following abbreviations are used for the multiplicities:…”

“…In recent years, multicomponent reactions have become popular due to their unique approach to synthesizing highly functionalized, complex, and diverse molecular structures from simple, easily available starting materials. [1][2][3] Their key advantages include mild conditions, atom, and energy efficiency, eco-compatibilities, effective formation of bonds, less waste production, a Greener approach, short duration, etc. Further multicomponent synthesis of heterocyclic structures using water as a solvent has great significance in the field of green chemistry.…”