A mild, efficient and improved protocol for the synthesis of novel indolyl crown ethers, di(indolyl)pyrazolyl methanes and 3-alkylated indoles using H4[Si(W3O10)3]

Novel dibenzo-18-crown-6 ether functionalized bis-benzimidazole derivatives: synthesis and antifungal evaluation

“…The sulfamic acid activates the ([C=O) carbonyl carbon of 4,4 0 -diformyl dibenzo-18-crown-6 ether (1) with formation of Schiff base (4) by removing the water molecules from 4,4 0 -diformyl dibenzo-18-crown-6 ether (1) and orthophenylene diamine (2). Then, the Schiff base (4) activates by protonation with acid, which on intramolecular cyclization with aniline forms intermediate 5, which on further air oxidation affords benzimidazole scaffold (3).…”

“…Macromolecules such as crown ethers are indispensable modules of macrocyclic systems in supramolecular chemistry, typically involving cyclized chains of repeating ethylene oxy [-(CH 2 CH 2 O)-] components [1,2]. Crown ethers have long been considered as biomimetics, due to their host-guest recognition as well as astonishing properties owing to the hydrophobicity of the outer ethylene group and inner oxygen atoms [3].…”

Fe(OTf) 3 -catalysed Friedel–Crafts reaction of benzenoid arenes with α,β-unsaturated carbonyl compounds: easy access to 1,1-diarylalkanes

“…Hydroarylation reaction with alkynes is also well investigated [77][78][79][80][81][82]. The Friedel-Crafts-type alkylation reaction with a variety of Michael acceptors is also extensively investigated, although these reactions are mostly limited to heteroarenes such as indoles, pyrroles and thiophenes [83][84][85][86][87][88][89][90][91][92]. By contrast, the intermolecular Friedel-Crafts-type reactions of benzenoid arenes with electron-deficient alkenes such as α,β-unsaturated cinnamic acid ester derivatives and chalcones as Michael acceptors are not recognized as substrates.…”

Synthesis of bis(indolyl)methanes using molten N-butylpyridinium bromide

“…Many of the methods were designed to use promoters, which include acids [11][12][13][14], surfactants [15], ammonium salts [16,17], trichloro-1,3,5-triazine [18], transition metal complexes [19][20][21][22][23][24][25], zeolites [26][27][28][29], molecular iodine [30,31], montmorillonite K-10 clay [32][33][34], under microwave irradiation [35]. In addition to this neoteric materials (ionic liquids) [36,37], protic solvent [38], and deep eutectic solvent systems [39] have also been used for the synthesis of BIMs.…”