The First High-yielding Benzyne Cyclisation Using a Phenolic Nucleophile: A New Route to Xanthenes

Abstract

Condensation of dianion 2 derived from aminobenzotriazole

Benzotriazole-Mediated Synthesis of Oxygen-Containing Heterocycles

“…The corresponding benzyne derivative underwent an intramolecular cyclization to give the iodoxanthenes 147 in excellent overall yields. This work demonstrated for the first time a viable method for the intramolecular trapping of benzyne derivatives by phenolic groups (Scheme 30) [50,51].…”

2,6-Pyridinedicarboxylic acid as an efficient and mild organocatalyst for the one-pot synthesis of xanthene derivative

“…Many methods using the synthesis of xanthene and benzoxanthene have been reported in the literature, including cyclodehydration [7][8][9][10], cyclization of polyclic aryl triflate esters [11], trapping of benzynes by phenols [12], intermolecular phenyl carbonyl coupling reactions of benzaldehydes and acetophenones [13] and cyclocondensation between 2-hydroxy aromatic aldehydes and 2-tetralone [14].…”

Nano Nickel-Cobalt Ferrite Catalyzed One Pot Synthesis of 14-Aryl-14H-Dibenzo[A, J]Xanthenes and 12-Aryl-8, 9, 10, 12-Tetrahydrobenzo[A]Xanthene-11-One Derivatives

“…Many synthetic strategies has been developed for synthesis of xanthenes and benzoxanthenes because of their pharmacological and biological activities such as cyclo-acylation of carbamates 11 , trapping of benzynes by phenol 12 , cyclocondensation between 2-hydroxy aromatic aldehydes and 2-tetralone 13 , cyclodehydrations 14 and cyclization of polycyclic aryltriflate esters 15 . Recently the synthesis of benzoxanthenes has been achieved by the condensation of aromatic aldehydes with 2-naphthol by cyclodehydration in the presence of various catalysts such as amberlyst-15 16 , sulfamic acid 17 , molecular iodine 18 , Al(HSO 4 .…”