Phosphane-Catalyzed Knoevenagel Condensation: A Facile Synthesis ofα-Cyanoacrylates andα-Cyanoacrylonitriles
作者:Jhillu S. Yadav、Basi V. Subba Reddy、Ashok K. Basak、Boddapati Visali、Akkirala Venkat Narsaiah、Kommu Nagaiah
DOI:10.1002/ejoc.200300513
日期:2004.2
Triphenylphosphane (TPP) has been utilized as a novel and efficient catalyst for the Knoevenagelcondensation of aldehydes with acidic methylene compounds such as ethyl cyanoacetate and malononitrile to afford substituted olefins. The reaction proceeds smoothly under mild and solvent-free conditions and the products are obtained in excellent yields with an E-geometry. This method is applicable for
Knoevenagel condensation catalysed with native and modified chitosan-based heterogeneous catalysts. The efficiency of our hydrogel organocatalysts, chitosan hydrogel beads and ureidyl-chitosan derivative hydrogel disks, was evaluated as function of pH, temperature and catalyst concentration by considering reaction rates, conversions, E/Z stereoselectivities, and kinetic studies of a model reaction between
A Simple, Efficient and Green Procedure for Knoevenagel Condensation in Water or under Solvent-free Conditions
作者:Ya-Qin Yu、Zhong-Liang Wang
DOI:10.1002/jccs.201200391
日期:2013.3
1,4‐Diazabicyclo[2.2.2]octane was used as an efficient catalyst in the Knoevenagelcondensation reaction of various kinds of aromatic/aliphatic/heterocyclic/αβ‐unsaturated aldehydes and ketones with active methylene compounds. This is a convenient and rapid method for Knoevenagelcondensation, which affords the corresponding substituted electrophilic alkenes in excellent yields. The reaction condition
A Simple, Efficient and Green Procedure for the Knoevenagel Condensation of Aldehydes with N-Methylpiperazine at Room Temperature under Solvent-Free Conditions
作者:Chhanda Mukhopadhyay、Arup Datta
DOI:10.1080/00397910802029364
日期:2008.6.20
Abstract Knoevenagelcondensation of aromatic, aliphatic, and heteroaromatic aldehydes with active methylene compounds such as ethylcyanoacetate, malononitrile, and cyanoacetamide proceed very smoothly at room temperature by simply mixing the ingredients together undersolvent-freeconditions in the presence of N-methylpiperazine in excellent yields of the E-configured products.
摘要 芳香族、脂肪族和杂芳香族醛与活性亚甲基化合物如氰乙酸乙酯、丙二腈和氰基乙酰胺的 Knoevenagel 缩合在室温下非常顺利地进行,方法是在 N-甲基哌嗪的存在下,在无溶剂条件下简单地将这些成分混合在一起,收率非常好的 E 配置产品。
Monosubstituted Malononitriles: Efficient One-Pot Reductive Alkylations of Malononitrile with Aromatic Aldehydes
been developed for the reductive alkylation of malononitrile with aromatic aldehydes. This new procedure has vastly improved the yield and efficiency of the process, and increased the scope of the aromatic aldehydes. Incorporating water as the catalyst in ethanol for the condensation step allows stoichiometric amounts of malononitrile and aldehyde to be employed. The reduction step takes place quickly