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Quinazolines are biologically potent heterocyclic compounds; however, their synthesis poses high challenges. In this present study, we have developed an inexpensive cobalt metal‐catalyzed acceptorless dehydrogenative pathway for the sequential synthesis of alkenylated quinazolines from benzhydrol via dehydrogenation, cyclization, and subsequent dehydrogenative sp3 C−H functionalization. This transformation holds potential owing to its commercially available key starting materials, good functional tolerance, moderate reaction conditions, environmental friendliness, and applicability for gram‐scale synthesis. Furthermore, the synthetic utility of the synthesized derivatives has been explored through various reactions, including reduction, halogenation, methoxylation, Michael addition, and spiro cyclization. Additionally, the photophysical properties indicate that the nitrogen atom of the synthesized derivatives readily undergoes a reversible protonation, leading to significant changes in colour. This characteristic presents an opportunity for the creation of pH sensors with colourimetric capabilities. [ABSTRACT FROM AUTHOR]

A facile Pd/Cu-cocatalyzed one-pot domino aldol condensation/Michael addition/Sonogashira coupling has been developed. The reaction of 2-chloro-3-formylquinolines (CFQs), 1 acetophenones (APs), 2 and terminal acetylenes, 3 by employing triethylamine as a base, solvent as well as a ligand under mild conditions gave highly functionalized 1,5-diphenyl-3-(2-(2-phenylethynyl)quinolin-3-yl)pentane-1,5-diones, 4a-j, Additionally accomplished Heck arylation using CFQs in the presence of Pd catalyst. The present methodology gave the desired synthetic building blocks in acceptable yields. [ABSTRACT FROM AUTHOR]

A series of quinoline-chalcones were synthesized from one-pot Friedlander annulation followed by Claisen–Schmidt condensation in the presence of tetrabutylammonium-ionic liquids (TBA-ILs) as a catalyst and base medium under MW-Irradiation. TBA-ILs is an emerging reaction medium instead of conventional organic solvents (VOCs). It is an efficient approach toward the C–C bond formation. The synthesized chalcones were evaluated further in vitro antimicrobial, antioxidant properties, in silico molecular docking analysis, and in vitro anticancer inhibition was achieved against MCF-7 breast cancer cell lines. Structure–activity relationships (SAR) studies were employed to improve in vitro/in vivo pharmacological activities to restrict the peripheral circulation's absorption, distribution, and metabolism. [ABSTRACT FROM AUTHOR]

Deep eutectic solvent (DES) catalyzed, Microwave-assisted one-pot conjugate Michael addition followed by annulation of nucleophiles, 4-hydroxy coumarin, 1,3-diketone with α,β-unsaturated carbonyl compounds (chalcones) toward benzopyran, pyranocoumarin, xanthene, dihydrofuran, 4-hydroxy-coumarin (warfarin analogs) derivatives has been achieved. It is a one-pot, solvent, metal-free, and green chemical approach with a clean reaction pathway, in high regio, stereo selectivities, and yields under milder MW-irradiation. The easily recoverable DES catalyst and eco-friendly reaction strategy are notable advantages of the current procedure. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 1,1,3-trisubstituted-1H-isochromenes, 3 is reported from isochromen-1-ones, 1 and Grignard Reagents, 2a-h through sequential Grignard reactions/acid-catalyzed cyclization. The cyclization underwent smoothly with montmorillonite K10 catalyst to obtain the 1,1,3-trisubstituted-1H-isochromenes in excellent yields. [ABSTRACT FROM AUTHOR]

Catalyst free efficient and straightforward method is accounted for the synthesis of 2,4-disubstituted quinazolines utilizing urea was seen as a modest, nontoxic, easily biodegradable, and powerful reaction medium. This productive and straight forward method furnished the corresponding 2,4-disubstituted quinazolines in significant yields employing a one-pot three-component reaction of 2-amino benzophenones, aldehyde, and urea under aerobic oxidation conditions. Additionally, 2-methyl-4-phenylquinazolines were synthesized using ammonium acetate with readily available 2-amino benzophenones. [ABSTRACT FROM AUTHOR]

An efficient Pd(OAc)2 catalyzed, Csp2-Csp bond formation through tautomerizable quinolinones by reacting with different alkynes furnished alkynyl quinolines in excellent yields. The C-OH bond activation is facilitated by using BOP reagent in the presence of Ruphos/THF/H2O system under copper-free aqueous conditions, which yields chemo-selectivity and could be a greater synthetic utility. [ABSTRACT FROM AUTHOR]

In the presence of heterogeneous catalyst Montmorillonite KSF (M-KSF) 2-chloro-3-formyl quinolines, 1 were successfully converted into regioselective 3-(quinolin-3-yl)pentane-1,5-diones, 3. A one-pot sequential reaction (aldol-condensation-Michael addition) of distinct acetophenones, 2 was efficient in an aqueous medium. [ABSTRACT FROM AUTHOR]

An efficient catalytic system comprising of Pd2dba3/P(t-Bu)3H.BF4/Cy2NMe –for the Heck coupling in the synthesis of 3-alkenyl isochromen-1-ones, 3 has been developed. Air stable alkyl phosphonium salt, [(t-Bu)3Ph]BF4 was found to be vital for the activation of 3- chloroisochromen-1-ones, 1 in regio-selective Heck coupling reactions. The technique has additionally been reached out to typharin, penicilisorin and artemidin analogs. [ABSTRACT FROM AUTHOR]

One-pot synthesis of quinolinyl amine nitriles, 8, was accounted from quinoline-3-carbaldehyde, 7, and amines (benzylic, aromatic, aliphatic, or hetero-aromatic) using Zn(CN)2/trifluoroethanol (TFE) system, an eco-friendly, and ambient protocol. Antidiabetic, anti-inflammatory, antioxidant, and molecular docking studies of 8a–l revealed moderate-to-good activity. [ABSTRACT FROM AUTHOR]

Xanthene-1,8(2H)-diones, 4 were obtained from 6-bromo-2-chloro quinoline-3-carboxaldehyde, 3 in water reflux and subsequently underwent Suzuki-Miyaura cross/Sonogashira/Stille coupling utilizing second generation XPhos Palladium preformed catalyst 1. Low catalyst loading, ambient temperature and wide scope of boronic acids, enantioselectivity are the advantages. [ABSTRACT FROM AUTHOR]

A series of spiro[indoline‐3,3'‐pyrrolizin]‐2'‐yl)‐4‐phenylquinoline‐3‐carboxylate 6 from 2‐amino‐5‐chlorobenzhydrol 1, benzyl alcohols 3, and methyl or ethyl acetoacetate 2 is reported by the Cu(OAc)2, TEMPO catalyzed dehydrogenative Friedlander annulation/sp3–CH‐functionalization/regioselective 1,3‐ dipolar cyclo‐ addition. Likewise, chimanine A analogues 7 were obtained using a similar strategy in DES (Deep Eutectic Solvents) as a reaction medium in excellent yields. [ABSTRACT FROM AUTHOR]

An efficient one‐pot strategy evolved in the synthesis of (E)‐4‐benzylidenylacridin‐1(2H)‐ones, (4 or 9) (E)‐2‐styryl quinoline‐3‐carboxamides (5 or 10) by sequential Suzuki–Miyaura coupling‐dehydrogenative Friedländer‐sp3 C–H activation. The 2‐amino‐5‐chloro benzhydrol 1, aromatic alcohol 2 or 6 ketones 3 or 3', and phenylboronic acid 7 underwent a smooth reaction in a basic deep eutectic solvent consisting of K2CO3 and ethylene glycol (DES‐1,1:1). DES‐1 could enable the Pd‐catalyzed Suzuki coupling reaction of 6, as well as the rapid oxidation of primary, secondary, and Suzuki coupled primary alcohols (2, 1, and 8) in the presence of an iridium catalyst and 1,10‐phenanthroline. The acidic DES‐2 (dimethyl urea/tartaric acid, 7:3) assists the Friedländer annulation and subsequent sp3‐C–H functionalization resulting in (E)‐4‐benzylidenylacridin‐1(2H)‐ones (4 or 9) and (E)‐2‐styryl quinoline‐3‐carboxamides (5 or 10). [ABSTRACT FROM AUTHOR]

Choline chloride (ChCl) based deep eutectic solvent (DES), facilitated the regioselective synthesis of (E)‐1‐(4‐phenyl‐2‐styrylquinolin‐3‐yl)ethan‐1‐one (4), and (E)‐3‐phenyl‐1‐(4‐phenyl‐2‐((E)‐styryl)quinolin‐3‐yl)prop‐2‐en‐1‐ones, (5) from the corresponding 2‐amino‐5‐chloro benzhydrol, (1) in one‐pot strategy. The 2‐methyl‐3‐acetylquinoline generated in situ from the 2‐amino‐5‐chloro benzhydrol, (1) and acetyl acetone, (2) via dehydrogenative Friedlander reaction in DES could enable subsequent regio‐selective C‐2 methyl group sp3 C–H activation and rapid alkenylation with alcohols, (3) to provide the desired (E)‐2‐styrylquinolin‐3‐yl)ethan‐1‐ones, 4 in short reaction time and high yields and purity. Likewise, through the simultaneous C‐2 and C‐3 sp3 C–H activation with aromatic alcohols, (3) the (E)‐2‐styrylquinolin‐3‐yl)prop‐2‐en‐1‐ones, (5) formation was carried out in DES in high yields and purity. The physicochemical properties viz., UV/Vis, and fluorescence studies of the synthesized compounds were investigated. The absorption and emission properties of these luminophores are attributable to the presence of auxochromes in the 6‐position of quinoline moiety, styryl‐functional group at the 2‐position, and the enone group at 3‐position. [ABSTRACT FROM AUTHOR]

A new method has been developed for the synthesis of imidazo[1,2‐a]pyridines, imidazo[2,1‐b]thiazoles, and benzo[d]imidazo[2,1‐b]thiazoles attached to a cycloalkyl or saturated heterocycle containing a tertiary hydroxy substitution. Readily available substituted 2‐aminopyridines, 2‐aminothiazoles, and 2‐aminobenzothiazoles were treated with bromohydroxycycloalkyl ethanones to afford the desired products in good yields. [ABSTRACT FROM AUTHOR]