Heterogeneous ditopic ZnFe<sub>2</sub>O<sub>4</sub>catalyzed synthesis of 4H-pyrans: further conversion to 1,4-DHPs and report of functional group interconversion from amide to ester
作者:Paramita Das、Arghya Dutta、Asim Bhaumik、Chhanda Mukhopadhyay
DOI:10.1039/c3gc42095g
日期:——
Highly stable, environmentally benign ZnFe2O4 nanopowder was prepared, characterized and applied in the one-pot, three-component synthesis of 4H-pyrans in water. The ZnFe2O4 catalyst provides both acidic (Fe3+) and basic functionalities (O2−) as the reaction requires. The advantages of this method lie in its simplicity, cost effectiveness, environmental friendliness and easier scaling up for large scale synthesis. Water was exploited both as a reaction medium as well as a medium for synthesis of the catalyst. Moreover, water was the only byproduct. The present report puts forward an application of 4H-pyrans for the synthesis of 1,4-DHPs. This is the first attempt towards the synthesis of 4H-pyran-3-carboxylate from 4H-pyran-3-carboxamide. The corresponding functional group interconversion from amide to ester is rare in organic synthesis.
成功制备、表征并应用了一种稳定且对环境友好的ZnFe2O4纳米粉,在水相中实现了4H-吡喃的一锅法三组分合成。ZnFe2O4催化剂同时提供了反应所需的酸性(Fe3+)和碱性(O2−)功能。该方法的优势在于其简单性、成本效益、环境友好性以及更易于放大进行大规模合成。水既被用作反应介质,也被用作催化剂的合成介质。此外,水是唯一的副产品。本报告提出了一种应用4H-吡喃合成1,4-二氢吡啶(1,4-DHPs)的方法。这是首次尝试从4H-吡喃-3-甲酰胺合成4H-吡喃-3-羧酸酯。在有机合成中,从酰胺到酯的功能团转换是罕见的。