Phosphoric acid supported on alumina (H
as an efﬁcient and reusable catalyst for the one-pot
synthesis of benzoxanthene pigments
Hamid Reza Shaterian
Received: 17 November 2012 / Accepted: 11 January 2013 / Published online: 26 January 2013
Ó Springer Science+Business Media Dordrecht 2013
Abstract Phosphoric acid supported on alumina (H
) is an efﬁcient
catalyst for the catalytic multi-component condensation reaction and a wide variety
of syntheses of benzoxanthene pigments in good yields. The remarkable features of
this new procedure are high conversions, shorter reaction times, cleaner reaction,
and simple experimental and work-up procedures.
Keywords Phosphoric acid Á Alumina Á Benzoxanthene Á
Heterogeneous catalyst Á Solvent-free
Multi-component processes have recently gained considerable economic and
ecological interest, as they direct to speciﬁc destinations essential principles of
synthetic efﬁciency and reaction design. Multi-component reactions (MCRs) have
been proven to be a very reﬁned and rapid way to access complex structures in a
single synthetic operation from simple building blocks and show high atom
economy and high selectivity .
Dyes have played an essential role in human history since primeval days. Dyes
are used in almost every commercial product such as food, clothing, pigments and
paints, etc. .
Derivatives of xanthene are commonly referred to collectively as xanthenes, and
among other uses are the basis of a class of dyes which includes ﬂuorescein, eosins,
and rhodamines. Xanthene dyes tend to be ﬂuorescent, yellow to pink to bluish red,
brilliant dyes .
H. R. Shaterian (&) Á K. Azizi Á N. Fahimi
Department of Chemistry, Faculty of Sciences, University of Sistan and Baluchestan,
PO Box 98135-674, Zahedan, Iran
Res Chem Intermed (2014) 40:1403–1414