Brønsted Acidic Ionic Liquid as an Efficient and Reusable Catalyst for Synthesis of 14-Aryl- or 14-Alkyl-14H-dibenzo[a,j]xanthenes under Solvent-Free Conditions

Abstract

A mild and efficient method has been developed for the preparation of 14-aryl-or 14-alkyl-14H-dibenzo[a,j]xanthenes from one-pot condensation of aldehydes with 2-naphthol using catalytic amount of Brønsted acidic ionic liquid ([TEBSA][HSO 4 ]) under thermal solvent-free conditions. Excellent yields, short reaction times, easy workup and reusability of the catalyst as well as solventfree conditions are advantages of this procedure.

K2FeZrP3O12 as an Efficient Catalyst for Friedel–Crafts Benzylation under Solvent-Free Conditions

“…In continuation of our efforts to develop facile and green chemistry, [16][17][18] in this paper we report the preparation of PIZP according to reported procedure and characterize it by comparing to authentic sample 15 and test the ability of this catalyst for benzylation of aromatic compounds under solvent-free conditions (Scheme 1) which results are summarized in Table 1. The catalyst can be kept under nitrogen atmosphere, in a desiccator on P 2 O 5 and used for months without decreasing its activity, while by keeping the catalyst in laboratory after a week its activity decreased darmatically and this was not mentioned by others.…”

Solvent Free, One Pot Synthesis of Symmetric Xanthene Dyes and Their Electrochemical Study

“…Due to the applicability of the xanthenes and benzoxanthenes, several synthetic protocols have been reported, including the reaction of alkylphenoxymagnesium halides with triethyl orthoformate 17 , the palladiumcatalysed cyclization of polycyclic aryltriflate esters 18 , the cyclocondensation reaction between 2-tetralone and 2-hydroxyarylaldehydes under acidic conditions 19 , and the reaction of the condensation of cyclic 1,3-diketones with aryl aldehydes catalysed by molybdate sulphonic acid 20 . Furthermore, 14-aryl14Hdibenzo [a, j] xanthene derivatives can be prepared by the condensation reaction of 2-naphthol with aryl aldehydes in the presence of different Lewis acids [21][22][23][24][25] and Bronsted acids [26][27][28][29] .The objective of the current research was to synthesize highly fluorescent, thermally and photochemically stable xanthene dyes which could be used in preference over usual fluorescent dyes like fluorescein and rhodamine dyes via short green route. To this end two series of xanthene derivatives (3a-e and 6a-e) from 4,4′-Oxydiphthalic anhydride and 1,4,5,8-Naphthalenetetra-carboxylic dianhydride have been synthesized via Friedel craft reaction in the presence of ammonium chloride.…”

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

“…Furthermore, 14-aryl-14H-dibenzo[a,j ]xanthene derivatives can be prepared by the condensation reaction of 2-naphthol with aryl aldehydes in the presence of different Lewis acids (Ding et al, 2007;Wang et al, 2008;Urinda et al, 2009;Wang et al, 2010;Soleimani et al, 2011;Tabatabaeian et al, 2011;Mirjalili et al, 2011;Zolfigol et al, 2012;Rao et al, 2012;Cao et al, 2013) and Brønsted acids (Gong et al, 2009;Hajipour et al, 2010;Rahmatpour, 2011;Ghassamipour & Sardarian, 2012;Zare et al, 2012).…”