Application of salicylic acid as an eco‐friendly and efficient catalyst for the synthesis of 2,4,6‐triaryl pyridine, 2‐amino‐3‐cyanopyridine, and polyhydroquinoline derivatives

Abstract

In this study, three eco‐friendly, efficient, and convenient protocols have been reported for one‐pot synthesis of 2,4,6‐triaryl pyridine, 2‐amino‐3‐cyanopyridine, and polyhydroquinoline derivatives using salicylic acid as a catalyst under solvent‐free condition. The reported protocols offer several significant advantages such as the application of a nontoxic, neutral, and cheap catalyst, environmentally friendly conditions, the easy isolation of products by filtering, short reaction times, simple methodology, and good yields.

Synthesis, properties, and application of the new nanocatalyst of double layer hydroxides in the one-pot multicomponent synthesis of 2-amino-3-cyanopyridine derivatives

“…Double-layered hydroxides known for more than a decade, are abundant in nature and easily extracted, and represent a large class of anion- and cation-exchangeable layered structures with the general formula [M 2+ (1-x) Mx 3+ (OH) 2 is](An - ) x/n.zH 2 O]. Metal cations that are used in divalent and trivalent form are Mn 2+ , Fe 2+ , Mg 2+ , Co 2+ , Zn 2+ , Ca 2+ and Mn 3+ , Fe 3+ , Co 3+ , Cr 3+ , Al 3+ and the anions used often contain carbonate, bromide, chloride or are nitrates 4 – 6 . There are various methods for the synthesis of LDHs, among which can be mentioned ion exchange, hydrothermal and co-precipitation methods.…”

“…Various synthesis methods have been reported for their synthesis, in which the multicomponent reactions of ammonium acetate, malononitrile, acetophenone, and aldehydes are the most important synthesis routes. A wide range of multicomponent syntheses have been reported by different catalysts, including: Boric acid sulfate nanocatalysts 21 , HBF 4 22 , microwave facile 23 , Amberlyst-15 24 , salicylic acid 4 , MNPs CoFe 2 O 4 @SiO 2 -SO 3 H 25 , nano solid magnetic acid, Fe 3 O 4 26 , Fe 3 O 4 @g-C 3 N 4 -SO 3 H 27 , Fe 3 O 4 @SiO2@(CH 2 ) 3 NH 28 , (CH 2 ) 2 O 2 P(OH) 2 29 , poly N,N-dimethylaniline-formaldehyde 30 , Copper Nanoparticles on Charcoal 31 , Fe 3 O 4 @Niacin 32 , Bu 4 N + Br -18 , Cu@imineZCMNPs 17 . However, simpler and milder methods for their synthesis are still valuable.…”

Synthesis of Quinoline and Polyhydroquinoline Derivatives Using Phloroglucinol Cored Amino Functionalized Dendritic Polymer as Catalyst

“…These chemicals have been shown to have a variety of medicinal functions, [30–34] including neuroprotectant, [35] platelet anti‐aggregatory action, [36–38] cerebral antischemic activity [39] in the treatment of Alzheimer's disease, [40] and as chemosensitizer in tumour therapy [41] . These examples show the extraordinary potential of dihydropyridine (polyhydroquinoline) derivatives as a source of promising therapeutic candidates [42–44] . In addition, the oxidation of these compounds to pyridines has been thoroughly investigated.…”

Hantzsch Reaction using Copper Nitrate Hydroxide- Containing Mesoporous Silica Nanoparticle with C 3 N 4 Framework as A Novel Powerful and Reusable Catalyst

“…Lately, remarkable attention has been developed to designing eco-friendly catalysts and synthetic procedures for the Hantzsch reaction. The environmentally benign processes comprise the use of effective, biodegradable, and economical catalysts and non-toxic systems such as solvent-free conditions, water, and supercritical uids (21)(22)(23)(24)(25).…”