Photocatalytic Giese Addition of 1,4-Dihydroquinoxalin-2-ones to Electron-Poor Alkenes Using Visible Light
作者:Jaume Rostoll-Berenguer、Gonzalo Blay、José R. Pedro、Carlos Vila
DOI:10.1021/acs.orglett.0c02953
日期:2020.10.16
The optimized reaction conditions provide a good yield for the radical conjugate addition products (44 examples) with a wide range of structurally different Michael acceptors. A gram scale reaction using sunlight irradiation is also described. Furthermore, several transformations were carried out with the Giese addition products.
使用Ru(bpy)3 Cl 2作为光催化剂和(PhO)2 PO 2 H作为添加剂,实现了1,4-二氢喹喔啉-2-酮与Michael受体的可见光光氧化还原催化偶联。优化的反应条件为具有广泛结构上不同的迈克尔受体的自由基共轭加成产物(44个实例)提供了良好的收率。还描述了使用阳光照射的克级反应。此外,使用Giese添加产品进行了几次转化。
Base-Promoted Tandem Cyclization for the Synthesis of Benzonitriles by C−C Bond Construction
作者:Cheng-Zhi Zhu、Yin Wei、Min Shi
DOI:10.1002/adsc.201701329
日期:2018.2.15
A facile synthesis of benzonitriles via a base‐promoted tandem cyclization reaction of α,β‐unsaturated enones having electron‐withdrawing group (EWG) and 2‐acyl‐acrylonitriles was developed. This new synthetic method to access benzonitriles is suitable for a wide range of substrates. A plausible reaction mechanism is proposed on the basis of previous literature and our own investigations.
A simple method for the preparation of functionalized trisubstituted alkenes and α,β,γ,δ-unsaturated carbonyl compounds by using natural amino acid l-tryptophan
作者:Ying Hu、Yan-Hong He、Zhi Guan
DOI:10.1016/j.catcom.2010.01.016
日期:2010.3
reactive acetylacetone and ethyl acetoacetate. The reactions were carried out at room temperature and gave good yields. It is a convenient entry for preparation of functionalizedtrisubstituted alkenes and α,β,γ,δ-unsaturated carbonyl compounds.
Enzyme catalytic promiscuity: The papain-catalyzed Knoevenagel reaction
作者:Wen Hu、Zhi Guan、Xiang Deng、Yan-Hong He
DOI:10.1016/j.biochi.2011.09.018
日期:2012.3
Knoevenagel reactions in DMSO/water. A wide range of aromatic, hetero-aromatic and α,β-unsaturated aldehydes could react with less active methylene compounds acetylacetone and ethyl acetoacetate. The products were obtained in moderate to excellent yields with Z/E selectivities of up to 100:0. This case of biocatalytic promiscuity not only widens the application of papain to new chemical transformations
Enantioselective Zinc-Mediated Conjugate Addition of Terminal Alkynes to Enones
作者:Gonzalo Blay、Luz Cardona、José R. Pedro、Amparo Sanz-Marco
DOI:10.1002/chem.201201765
日期:2012.10.8
Zinc for conjugate alkynylation: The enantioselectiveconjugateaddition of terminalalkynes to 2‐arylidene‐1,3‐diketones in the presence of diethylzinc and a catalytic amount of (R)‐VANOL has been developed. The reaction can be applied to different aromatic and heteroaromatic alkynes and enones, giving the expected products in good yield and with enantiomeric excesses up to 91 %. The products can