Calcined eggshells as a highly efficient catalyst for the synthesis of 2-amino 4H-chromene derivatives
作者:Swati D. Jadhav、Suresh S. Patil
DOI:10.1007/s11164-023-05109-0
日期:2023.11
A highly efficient and convenient green method using highly efficient natural catalyst calcined eggshell (CES) is described for synthesis of 2-amino 4H-chromenederivatives in ethanol–water system. The new inexpensive green catalyst CES is obtained from waste natural resources. This method offers mild reaction conditions at ambient temperature, with short reaction times and clean work up procedures
NiZnFe2O4: an eco-compatible and magnetically separable catalyst for multicomponent synthesis of 2-amino-4H-chromenes
作者:Sandip P. Patil、Sachinkumar K. Shinde、Vikram M. Desai、Arvind A. Pawar、Jeevan S. Ghodake、Suresh S. Patil
DOI:10.1007/s11164-023-05043-1
日期:2023.8
friendly reusable catalyst for the synthesis of 2-amino-4H-chromene derivatives via a one-pot, three-component condensation reaction of various salicylaldehydes and malononitrile or ethyl cyanoacetate with nitromethane or nitroethane in ethanol at room temperature. There have been no reports of nickel zinc ferrite being used as a catalyst. The catalyst was specified by using several techniques, including DSC–TGA
合成了可磁分离的非均相镍锌铁氧体 (NiZnFe 2 O 4 ) 催化剂,并首次作为环境友好的可重复使用催化剂用于合成 2-amino-4 H-色烯衍生物通过各种水杨醛和丙二腈或氰基乙酸乙酯与硝基甲烷或硝基乙烷在室温下在乙醇中的一锅三组分缩合反应。还没有镍锌铁氧体用作催化剂的报道。该催化剂是通过使用多种技术指定的,包括 DSC–TGA、FT-IR、X 射线衍射 (XRD)、能量色散 X 射线光谱 (EDX)、BET 和扫描电子显微镜 (SEM)。本协议提出了一些好处,包括绿色反应条件、简单的反应后处理、反应时间短、产品产量高、无色谱纯化以及非均相催化剂的高效率。更重要的是,这种催化剂是使用一个简单的外部磁铁从反应混合物中回收的, 图形概要
Aqueous-mediated Michael Addition of Active Methylene Compounds with Nitroalkenes
作者:Wenkai Dong、Dongcheng Xu、Jianwu Xie
DOI:10.1002/cjoc.201200228
日期:2012.8
A simple, atom economical and highly efficient green protocol has been developed for the synthesis of Michael adducts of nitroalkenes and 2‐amino‐2‐chromene derivatives by Michael addition of activemethylenecompounds (such as malononitrile and ethyl cyanoacetate) to nitroalkenes under aqueous‐mediated conditions. This green approach provided the desired products in high yields and the reaction scope