Synthesis of Fatty Acetoacetates Under Microwave Irradiation Catalysed by Sulfamic Acid in a Solvent-Free System
The 1,3-dicarbonyl compounds are important building blocks to obtain products with various biological activities and technological applications. In this work, we used a simple transesterification method to develop fatty acetoacetates in a solvent-free medium using a green catalyst, sulfamic acid (NH2SO3H), under microwave irradiation. The experimental results demonstrate good yields in a short reaction time (13 min), which makes this method an efficient approach to synthesize fatty acetoacetates from a wide range of saturated, unsaturated, and polyunsaturated long chain fatty alcohols, and ricinoleic derivatives. Experiments of recycling of the catalyst were performed and no decrease in catalytic activity of sulfamic acid was observed.
KeywordsCastor oil Renewable resources Transesterification reaction 1,3-dicarbonyl compounds Microwave-assisted
The authors are thankful for financial support from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação de Apoio à Pesquisa do Estado do Rio Grande do Sul (FAPERGS/PRONEM), and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). Fellowships from CAPES (A. C. H. Weber) and CNPq (D. Russowsky and M. G. Montes D’Oca) are also acknowledged.
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Conflict of interest
The authors declare no conflict of interests.
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