A Study of the Reactions of 3‐Bromopropenals with Anilines for the Synthesis of α‐Bromo Enaminones
作者:Sundaram Suresh、Prakash Bhimrao Patil、Pao‐Hsing Yu、Chia‐Chi Fang、Yin‐Zhi Weng、Veerababurao Kavala、Ching‐Fa Yao
DOI:10.1002/adsc.202100779
日期:2021.11.9
The reactions proceed via the p-toluenesulfonic acid monohydrate (TsOH ⋅ H2O) catalyzed reactions of 3-bromopropenals with anilines in dimethyl sulfoxide (DMSO) and does not require an external brominating agent. The chemoselective 1,2-addition was accomplished by employing aniline with a sterically hindered electron-withdrawing group attached at the ortho-position. In addition, the reactions involving
Divergent NHC-Catalyzed Oxidative Transformations of 3-Bromoenal: Selective Synthesis of 2<i>H</i>-Pyran-2-ones and Chiral Dihydropyranones
作者:Gang Wang、Xia Chen、Gaohan Miao、Weijun Yao、Cheng Ma
DOI:10.1021/jo400950j
日期:2013.6.21
A selectivesynthesis of either 2H-pyran-2-ones (4) or chiral dihydropyranones (6) from the same substrates of 3-bromoenals and 1,3-dicarbonyl compounds upon oxidative N-heterocyclic carbene catalysis is presented. It is shown that the oxidative transformation of 3-bromoenals under NHC catalyst can be well controlled to proceed through two pathways, i.e., elimination of reducible β-bromide or by an
into each of the furan units, are rapidly and efficiently synthesized by de novo metal-free synthesis of α-bi(arylfuran) monomers. The characterization of α-oligo(arylfuran)s demonstrates that photoelectric properties of coplanar α-oligo(arylfuran)s can be tuned through varying aryl groups with different electrical properties. These novel α-oligo(arylfuran)s have good hole transport capacity and can function
allows the divergent and practical de novo synthesis of various α-furanyl pyrroles and α-cyclopropenyl pyrroles derivatives with good to excellent yields and high efficiency under mild conditions. This approach features readily accessible starting materials, high functionalgroup compatibility, step economy and scalability, which would complement previous methods and support expansion of the toolbox for
N-Heterocyclic Carbene-Catalyzed δ-Carbon LUMO Activation of Unsaturated Aldehydes
作者:Tingshun Zhu、Chengli Mou、Baosheng Li、Marie Smetankova、Bao-An Song、Yonggui Robin Chi
DOI:10.1021/jacs.5b02219
日期:2015.5.6
An N-heterocyclic carbene (NHC) catalyzed domino reaction triggered by a delta-LUMO activation of alpha,beta-gamma,delta-diunsaturated enal has been developed for the formal [4 + 2] construction of multisubstituted arenes and 3-ylidenephthalide. These two products, formed in a highly chemo- and regioselective manner, were obtained via different catalytic pathways due to a simple change of the substrate. The activation of the remote delta-carbon of unsaturated aldehydes expands the synthetic potentials of NHC organocatalysis.