A new MCM-41 supported HPF6 catalyst for the library synthesis of highly substituted 1,4-dihydropyridines and oxidation to pyridines: report of one-dimensional packing towards LMSOMs and studies on their photophysical properties

作者：Ray Suman^*; Brown Mike; Bhaumik Asim; Dutta Arghya; Mukhopadhyay Chhanda

来源：Green Chemistry, 2013, 15(7): 1910-1924.

DOI：10.1039/c3gc40441b

A new heterogeneous MCM-41 silica supported HPF6 catalyst has been synthesized and characterized using an array of sophisticated analytical techniques like BET, XRD, HRTEM, EDX, Si-29 MAS NMR, TGA, FTIR, and pH measurement. The broad applicability of silica-HPF6 was probed through a library synthesis of highly substituted 1,4-dihydropyridines (1,4-DHPs). The 1,4-DHPs are further oxidized to pyridines with aqueous H2O2 as stoichiometric oxidant which is considered as an abundant and green oxidant. The pyridines spontaneously generate low molecular mass self-aggregated organic materials (LMSOMs). Their one-dimensional packing and interesting photophysical properties are reported. Synthesis using water as a solvent is of paramount importance for its sustainable green impact. Further, carbon dioxide and water were the only by-products, which added to its attractiveness. This silica-HPF6 catalyst retained its activity even after being exposed to ambient atmosphere for 10 days.

• 出版日期2013