Synthesis of functionalized chromene and spirochromenes using l -proline-melamine as highly efficient and recyclable homogeneous catalyst at room temperature
commercially cheap l-proline and melamine for the synthesis of chromenes and spirochromenes (spirooxindoles) via multicomponent reactions at room temperature. Systematic studies were conducted in order to achieve desired reactivity and recyclability of the catalyst using various α-amino acids and aromatic amines as donor-acceptor pairs. Among the screened combinations, l-proline and melamine (3:1 ratio;
A mild, simple and convenient procedure for the synthesis of spiro-oxindole heterocycles containing fused 4H-pyran ring and also bis-2-amino-4H-pyrans derivatives was described using C4(DABCO-SO3H)2·4Cl as a nano, efficient, cheap, and reusable catalyst under mild and homogeneous conditions.
One-Pot Three-Component Synthesis of Spirooxindoles Catalyzed by Hexamethylenetetramine in Water
作者:Guo-Dong Wang、Xiao-Nan Zhang、Zhan-Hui Zhang
DOI:10.1002/jhet.994
日期:2013.1
convenient, and multicomponent strategy for synthesis of spirooxindole derivatives has been developed. This strategy provides a rapid access to construct a diversity‐oriented library of spirooxindoles by using three simple and readily available isatin, malononitrile or cyanoacetic ester, and 1,3‐dicarbonyl compound catalyzed by hexamethylenetetramine in water.
Efficient One-Pot Synthesis of Spirooxindole Derivatives Catalyzed by <scp>l</scp>-Proline in Aqueous Medium
作者:Yuling Li、Hui Chen、Chunling Shi、Daqing Shi、Shunjun Ji
DOI:10.1021/cc9001185
日期:2010.3.8
An efficient one-potsynthesis of spirooxindole derivatives by three-component reaction of isatins, malononitrile (cyanoacetic ester) and 1,3-dicarbonyl compounds in water in the presence of l-proline is reported. This new protocol has the advantages of environmental friendliness, higher yields, shorter reaction times, low cost, and convenient operation.
Na2EDTA: an efficient, green and reusable catalyst for the synthesis of biologically important spirooxindoles, spiroacenaphthylenes and spiro-2-amino-4H-pyrans under solvent-free conditions
For the first time, the organic salt Na2EDTA was used as a catalyst for an effective and facile preparation of spiro-4H-pyrans via single-pot three-component condensation of isatin/acenaphthoquinone/ninhydrin, malononitrile, and CH-acids through Knoevenagel–Michael–annulation sequence. This new protocol employing Na2EDTA, which is a green, recyclable, and inexpensive catalyst, offers advantages such
第一次,将有机盐Na 2 EDTA用作催化剂,通过Isatin / ac萘醌/茚三酮,丙二腈和CH-酸的单锅三组分缩合反应,有效而便捷地制备spiro-4 H -pyrans通过Knoevenagel–Michael–环形序列。这项采用Na 2 EDTA的新方案是一种绿色,可回收且廉价的催化剂,具有无溶剂,高效反应条件,反应时间短(10-15分钟),后处理容易,收率高等优点。比其他环境合成方法更经济。