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www.ccsenet.org/ijc

International Journal of Chemistry

Vol. 2, No. 2; August 2010

One-pot Preparation of β–amino Carbonyl Compounds by Mannich Reaction Using MgO/ZrO2 as Effective and Reusable Catalyst Deepak.M. Nagrik (Corresponding author) Department of Chemistry, PLIT and MS Buldana-443001, M.S., India E-mail: dmnagrik@rediffmail.com D.M.Ambhore P.G.Department of Chemistry, Jijamata Mahavidyalaya Buldana-443001, M.S., India Manoj.B. Gawande (Corresponding author) Departamento de Química, Faculdade de Ciências and Tecnologia Quinta da Torre, 2829-516 Caparica, Portugal E-mail: mbgawande@yahoo.co.in, m.gawande@fct.unl.pt Abstract A new one-pot and efficient three-component condensation of aldehydes, ketones, and amines in the presence of MgO/ZrO2 as an inexpensive and effective catalyst for the synthesis of β-amino carbonyl compounds by Mannich reaction is described. The present methodology offers several advantages, such as good yields, short reaction times and a recyclable catalyst with a very easy work up. Keywords: Multi-component reaction, MgO/ZrO2, heterogeneous catalyst, β-amino Carbonyl compounds 1. Introduction The synthesis of natural molecules, pharmaceuticals and other nitrogenous biologically active compounds has long been a significant branch of organic synthesis. (B. List, 2002; 2000; R. O. Duthaler, 2003) The Mannich reaction provides one of the most basic and useful methods for the synthesis of such compounds. Multi-component reactions (MCRs) are important for the achievement of high levels of brevity and diversity. They allow more than two simple and flexible building blocks to be combined in practical, time-saving one-pot operations, giving rise to complex structures by simultaneous formation of two or more bonds, according to the domino principle. (Zhu, J., 2005) MCRs contribute to the requirements of an environmentally friendly process by reducing the number of synthetic steps, energy consumption and waste production. Researchers have transformed this powerful technology into one of the most efficient and economic tools for combinatorial and parallel synthesis. (Zhu, J., 2005; Beck, B., 2000) Due to their inherent simple experimental procedures and their one-pot character, they are perfectly suited for automated synthesis. An amine, two carbonyl compounds and catalysts are used to produce β-amino carbonyl compounds (Scheme1) β -amino carbonyl compounds are very useful in pharmaceutical and other biologically related areas of chemistry. One of the many synthetic routes to these compounds is the Mannich reaction which brings together three compounds under appropriate catalytic conditions. These simplified reaction systems fulfill several of the principles of green chemistry including the use of recyclable catalysts and reduced auxiliaries. Mannich reaction is one of the most important C-C bond forming reactions in organic synthesis for the preparation of secondary and tertiary amine derivatives (M. Arend, 1998). These amines are further used for the synthesis of many intermediates, biologically active and natural products such as alkaloids and polyketides. The products of Mannich reaction are mainly β -amino carbonyl compounds and its derivatives that are used for the synthesis of amino alcohols, peptides, and lactams and as precursors to optically active amino acids. The conventional catalysts for classical Mannich reaction of aldehydes, ketones and amines involve mainly organic and mineral acids like proline (B. List, 2002; 2000; R.O. Duthaler, 2003), acetic acid (K. Mogilaiah, 2002),

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ISSN 1916-9698

E-ISSN 1916-9701

www.ccsenet.org/ijc

International Journal of Chemistry

Vol. 2, No. 2; August 2010

p-dodecylbenzenesulfonic acid (K. Manabe, 2001) and some Lewis acids (S. Kobayashi, 2002; P. Desai, 2000). They often suffer from the drawbacks of long reaction times and harsh reaction conditions, toxicity and difficulty in product separation, which limit its use in the...
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