Application of [PVP-SO₃H] HSO₄ as Powerful Polymeric-Based Solid Acid Catalyst for Hantzsch Synthesis of Polyhydrohydroquinolin-5(1H)-One

Application of Cyclohexane‐1,3‐diones in the Synthesis of Six‐Membered Nitrogen‐Containing Heterocycles

“…[33] Generally, 1,4-dihydropyridine derivatives are synthesized commonly via Hantzsch reaction using cyclohexane-1,3-dione, aldehydes, β-ketoesters and different amines. [34][35][36][37] These Nheterocycles are prepared in the presence of various recyclable catalysts such as NiO/ZrO 2 , [38] nanocrystalline CdS thin film, [39] cellulose template embedded Cu bionanocomposite, [40] γcyclodextrin, [41] nicotinic acid, [42] amine-functionalized graphene oxide nanosheets, [43] [PVP-SO 3 H] HSO 4 , [44] NiFeTi calcined layered double hydroxides, [45] periodic mesoporous organosilica supported manganese, [46] highly monodisperse PdRuNi nanoparticles on graphene oxide, [47] and Fe 3 O 4 @SiO 2 nanoparticles. [48] These methods offer several advantages such as short reaction times, good yields, excluding toxic solvents, easy recovery and recyclability of the catalyst, without the significant loss of yield after many runs.…”

Piperazinium Nano Silica Sulfonate: An Efficient Catalyst for the Hantzsch Reaction

“…Because of their above mentioned importance numerous reagents have been reported for the acceleration of the synthesis of dihydropyridine and polyhydroquinoline derivatives which of them palladium (0) nanoparticles, [16] K 7 [PW 11 CoO 40 ], [17] p-TSA, [18] Cs 2.5 H 0.5 PW 12 O 40 , [19] ionic liquids, [20,21] ceric ammonium nitrate (CAN), [22] Hf(NPf 2 ) 4 , [23] polymer, [24] HYzeolite, [25] BINOL-phosphoric acid derivatives, [26] HClO 4 ⋅ SiO 2 , [27] alumina sulfuric acid (ASA), [28] Yb(OTf) 3 , [29] Sc(OTf) 3 , [30] Bi-(NO 3 ) 3 ⋅ 5H 2 O, [31] nickel nanoparticle, [32] MgO nanoparticles, [33] Zn-VCO 3 hydrotalcite [34] and La 2 O 3 [35] are examples. Although these procedures caused a great extent of improvement, but most of them suffer from drawbacks such as need to use of stoichiometric amounts of reagents or metal precursors, unsatisfactory product yields, use of volatile organic solvents, harsh reaction conditions, non-recoverability of the catalyst, tiresome work-up and moisture sensitivity.…”