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Chamosite, a naturally occurring clay as a versatile catalyst for various organic transformations

Published online by Cambridge University Press:  09 July 2018

R. Arundhathi ,
B. Sreedhar  and
G. Parthasarathy
R. Arundhathi
Affiliation:
Inorganic and Physical Chemistry Division, Indian Institute of Chemical Technology (Council of Scientific and Industrial Research), Hyderabad-500007, India
B. Sreedhar*
Affiliation:
Inorganic and Physical Chemistry Division, Indian Institute of Chemical Technology (Council of Scientific and Industrial Research), Hyderabad-500007, India
G. Parthasarathy
Affiliation:
National Geophysical Research Institute (Council of Scientific and Industrial Research), Hyderabad 500007, India
*
*E-mail: sreedharb@iict.res.in
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Abstract

The chlorite-group mineral chamosite occurs in nanocrystalline form (~200 nm grain size) as a naturally occurring clay in the Quaternary marine sedimentary deposits near Kudiamozhi, Tuticorin District, Tamil Nadu, India; samples were used in this study as a reusable catalyst. The clay has the usual alternating tetrahedral-octahedral-tetrahedral silicate/aluminate/silicate layer structural arrangement (sometimes called the 2:1 silicate or talc layer structure). The interlayer and the t-o-t layer are bound together by both electrostatic and hydrogen-bonding forces. This natural clay catalyst has been well characterized by various techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), X-ray diffraction (XRD), temperature programmed desorption (TPD), thermal analysis and BET surface area measurements (Sreedhar et al., 2009); it has been utilized for various organic transformations such as acylation of alcohols and amines, cyclization of arylaldehydes with O-phenylenediamines and C-O bond formation reactions.

Keywords

chamositenatural clayalcoholsaminesacylationO-phenylenediaminesbenzaldehydescyclizationaryliodidesphenolsethersTamil NaduIndia
Type
Research Article
Information
Clay Minerals , Volume 45 , Issue 3 , September 2010 , pp. 281 - 299
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2010

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