One-Pot Synthesis of Hexahydroquinolines via Hantzsch Four-Component Reaction Catalyzed by a Cheap Amino Alcohol

Magnetic‐based picolinaldehyde–melamine copper complex for the one‐pot synthesis of hexahydroquinolines via Hantzsch four‐component reactions

“…The products of the reactions together with the experimental melting points are given in Table . Although the reaction yields are almost identical to those reported in the literature, for some derivatives such as products 1 , 9 and 11 , the reaction time is short (minutes versus half an hour) and for some products, including 3 , 6 and 12 , the reaction time is longer than those reported …”

“…Synthesis of novel HHQ derivatives via efficient approaches and evaluation of the pharmacological properties are the main aims of the research. Considering the above discussion, various catalysts such as γ‐Fe 2 O 3 , SBA‐15/SO 3 H nanoreactor, KH 2 PO 4 , sulfamic acid‐functionalized nano‐titanium dioxide, nano‐CoAl 2 O 4 , nano‐ZrO 2 ‐SO 3 H, ZrOCl 2 ⋅8H 2 O, silica‐bonded imidazolium–sulfonic acid chloride, nano‐Fe 3 O 4 –TiO 2 –SO 3 H, 1,3‐disulfonic acid imidazolium hydrogen sulfate, amino alcohol, basic isoreticular metal–organic framework (IRMOF‐3), SBA‐SO 3 H, [MPIm][HSO 4 ]@SBA‐15, SBA‐15/NHSO 3 H and ionic liquids grafted onto graphene oxide have been used in the synthesis of HHQs and DHPs. Although impressive successes have been achieved, most of the developed catalysts suffer from long reaction time (half an hour to several hours), and not so simple procedures for separation of the catalyst.…”

Convenient One-Pot Room Temperature Synthesis of 2-(trifluoromethyl)-1,2,3,4,7,8-hexahydroquinolin-5(6H)-one derivatives via Catalyst-Free Multicomponent Reactions

“…On the basis of this phenomenon, we wanted to know whether this model reaction could be operated under catalyst-free condition. In our delight, when the reaction was operated under catalyst-free condition, it could be carried out smoothly and obtained high yield (Table 1, entry [11][12]. Further studying to show the reaction gave the better yields without using any catalyst in 5 h. Then, the effects of temperature on reaction were examined also, and the results indicated that the low temperature was favorable to obtaining good yields.…”

“…In recent years, several efficient methods for the synthesis of hexahydroquinoline derivatives have been reported from using the different techniques and catalysts, such as, microwaves [6], ionic liquids [7], n-BuOH [8], P-TSA [9], ZnCl 2 or ZnO [10], ANP [11], Triton X-100 aqueous micellar media [12], PaCl 2 [13], and so on. On the basis of the aforementioned investigation, and as a continuation of our interest in developing efficient and environmentally benign procedures for preparation of hexahydroquinolines derivatives, herein, we reported an efficient method for preparation 2-(trifluoromethyl)-1,2,3,4,7,8-hexahydroquinolin-5(6H)-one derivatives from four-component reactions.…”

Design, characterization and application of silica-bonded imidazolium-sulfonic acid chloride as a novel, active and efficient nanostructured catalyst in the synthesis of hexahydroquinolines

“…One of the important categories of DHPs with a modified structural scaffold, is hexahydroquinolines (HHQs) which could be synthesized through the onepot four-component condencation reaction between aromatic aldehydes, dimedone (5,5-dimethylcyclohexane-1,3-dione), β-ketoesters and ammonium acetate (Hantzsch synthesis) using various catalysts such as FeF 3 [10], K 7 [PW 11 CoO 40 ] [11a], PPA-SiO 2 [11b] and HClO 4 -SiO 2 [11c]. Moreover, some other methods and catalysts have been introduced for the preparation of HHQs [12][13][14][15][16][17][18][19][20][21][22][23]. Quinolines which have a 1,4-dihydropyridine structure are of importance as they have been extensively used in medicinal chemistry.…”