Single step synthesis of coumarin derivatives over Al-MCM-41 and its supported catalysts under solvent-free condition

Autor:	K. Venkatachalam, Velayutham Murugesan, S. Sudha, S. Vishnu Priya, J. Herbert Mabel, Muthiahpillai Palanichamy
Rok vydání:	2008
Předmět:	Process Chemistry and Technology Resorcinol Molecular sieve Catalysis chemistry.chemical_compound chemistry MCM-41 Ethyl acetoacetate Pyridine Organic chemistry Phosphotungstic acid Physical and Theoretical Chemistry Pechmann condensation Nuclear chemistry
Zdroj:	Journal of Molecular Catalysis A: Chemical. 291:22-29
ISSN:	1381-1169
DOI:	10.1016/j.molcata.2008.04.021
Popis:	Al-MCM-41 (Mobil Composition Mater) (Si/Al = 25) molecular sieve was synthesized hydrothermally and 20 and 40 wt% phosphotungstic acid (PW) was supported on it. The materials were characterized using XRD, pyridine adsorbed FT-IR, 31P and 1H MAS NMR techniques. Catalytic performance of the materials was examined in the liquid phase condensation of resorcinol and ethyl acetoacetate. 7-Hydroxy-4-methylcoumarin was the only product observed in this reaction. The results revealed that 20 wt% PW/Al-MCM-41 is found to be more active than other catalysts. The reaction parameters were optimized to obtain high selectivity of the desired product at maximum resorcinol conversion. The reaction was also performed with substituted phenolic derivatives and ethyl acetoacetate in order to realize the substituent effect.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::b0a6c87b91fbce06992171681e7dde80 https://doi.org/10.1016/j.molcata.2008.04.021 Zobrazit plný text záznamu Full Text from ScienceDirect