Iodine-catalyzed efficient synthesis of xanthene/thioxanthene-indole derivatives under mild conditions

Abstract

<p>An efficient synthesis of xanthene/thioxanthene-indole derivatives has been developed through iodine-catalyzed nucleophilic substitution reaction of xanthen-9-ols and thioxanthen-9-ol with indoles.</p>

Introduction of a trinuclear manganese(iii) catalyst on the surface of magnetic cellulose as an eco-benign, efficient and reusable novel heterogeneous catalyst for the multi-component synthesis of new derivatives of xanthene

“…The synthesis of new compounds comprising heterocyclic systems grabs an important position in the scope of synthetic organic chemistry. [7][8][9] xanthene and its derivatives have become an important class of organic chemistry in the last few decades because of their wide range of biological and pharmaceuticals such as anti-inammatory, 10 antibacterial, 11 anti-plasmodial, 12 antidepressants, 13 antimalarial agent 14 and antiviral. 15 They also have basic applications in biodegradable processes such as photodynamic therapy, 16 agrochemicals, 17 uorescent materials, 18 laser technologies, 19 and luminescent sensors.…”

Molecular Iodine‐Catalysed Reductive Alkylation of Indoles: Late‐Stage Diversification for Bioactive Molecules

“…Molecular iodine, an eco‐friendly and inexpensive reagent, has found widespread application in synthetic organic chemistry [5b,12] . Notably, it could serve as a powerful substitute for transition‐metal catalyst, which is extremely attractive to the pharmaceutical industry.…”

Transition-metal-free intramolecular Friedel–Crafts reaction by alkene activation: A method for the synthesis of some novel xanthene derivatives

“…To summarize the main syntheses of these studies: in particular, transition metal-catalyzed cascade benzylation–cyclization [ 17 ], cyclization of polycyclic aryl triflate esters [ 18 ], reaction of β-naphthol and aldehydes [ 19 – 20 ] or inter- or intramolecular coupling of arynes by aldehydes or phenols [ 21 – 24 ], and Lewis acid-catalyzed cyclization of salicylaldehydes and cyclohexenones or tetralones [ 25 ]. Some other new and prominent synthesis methods of xanthenes are the tandem arylation/Friedel–Crafts reaction of o -hydroxy bisbenzylic alcohols with diaryliodonium salts [ 26 ], the Sc(OTf) 3 -catalyzed domino reaction [ 27 ], and the iodine-catalyzed nucleophilic substitution reaction of xanthen-9-ol [ 28 ]. As an example of an intramolecular hydroarylation of an olefin, 9,10-dihydroacridines, which are N derivatives of xanthenes, were synthesized using the combination of hexafluoroisopropanol and triflimide as a catalyst [ 29 ].…”