Efficient one-pot synthesis of 14-aryl-14H-dibenzo[a,j]xanthene derivatives promoted by niobium pentachloride

Abstract

A simple and efficient procedure for the synthesis of 14-aryl-14H-dibenzo[a,j ]xanthene derivatives through one-pot condensation of 2-naphthol with aryl aldehydes in the presence of niobium pentachloride is described. The reactions were carried out using 25 mole % of NbCl5, at ambient temperature, and in acceptable reaction times, affording excellent yields of the products.

Facile and efficient synthesis of xanthenedione derivatives promoted by niobium pentachloride

“…Xanthene derivatives can be prepared by several methods: cyclodehydration (Bekaert et al, 1992), the trapping of benzynes by phenols (Knight & Little, 2001), the palladium-catalysed cyclisation of polycyclic aryltriflate esters (Wang & Harvey, 2002), a simple and efficient procedure for the synthesis of xanthene derivatives through one-pot condensation of 2-naphthol with aryl aldehydes in the presence of niobium pentachloride (Bartolomeu et al, 2014), the condensation of cyclohexane-1,3-diones and aromatic aldehydes in the presence of solid acids (Karami et al, 2013a), amongst others (Horning & Horning, 1946;John et al, 2006;Saini et al, 2006;Zhang & Tao 2008;Zhang & Liu, 2008;Wang et al, 2008;Urinda et al, 2009;Lü et al, 2009;Maleki et al, 2011;Soleimani et al, 2011;Pramanik & Bhar, 2012;Dharma Rao et al, 2012;Karami et al, 2013bKarami et al, , 2013aKarami et al, , 2014Li et al, 2013;Cao et al, 2013;Shirini et al, 2013;Iniyavan et al, *Corresponding author, e-mail: lcsilva@fc.unesp.br 2014; Shirini et al, 2014Shirini et al, , 2015Preetam et al, 2015;Ilangovan et al, 2011). However, some of these methods involve long reaction times, extreme reaction conditions, expensive reagents and unsatisfactory yields, hence the improvement of these syntheses has been the target of several studies.…”

14-(4-Chlorophenyl)-14H-dibenzo[a,j]xanthene

“…In the arena of materials, dibenzo [a,j]xanthene derivatives have been reported to be promising hole-transporting materials for organic optoelectronic devices (Martins et al, 2017). Many reports on the synthesis of this class of compounds have been reported (Bartolomeu et al, 2014;Mirjalili et al, 2011). The present study of the title compound is a part of our work on the rapid synthesis of substituted dibenzo [a,j]xanthene derivatives as potential optical materials.…”

Highly Efficient Synthesis of 1-Thioamidoalkyl-2-naphthols and 14-Aryl-14H-dibenzo[a,j]xanthenes using a Novel Ionic Liquid: Catalyst Preparation, Characterization and Performing the Reactions

“…A mixture of arylaldehyde (1 mmol), 2-naphthol (2 mmol) and [TEASA][TFA] (0.044 g, 0.15 mmol) was initially stirred by a magnet at 100 °C, and after the reaction was solidified, it was stirred with a small rod at that temperature. After the reaction was completed {as monitored by TLC) n-hexane/ethyl acetate: 3/1)} , the mixture was cooled to room temperature, and the solid residue (crude product) was purified by recrystallization from hot ethanol (95%) [8,[32][33][34][35][36][37][38][39][40].…”

“…Moreover, these compounds can be applied as pHsensitive fluorescent materials for visualization of biomolecules, as sensitizers in photodynamic therapy, and in laser technology [29][30][31]. The general method for synthesis of 14-aryl-14Hdibenzo [a,j]xanthenes, as a significant class of xanthenes, involves the reaction of arylaldehydes with 2-naphthol in the presence of a catalyst [8,[32][33][34][35][36][37][38][39][40].…”