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
Exploiting Hydrazones To Improve the Efficiency of 6π-Electrocyclization Reactions of 1-Azatrienes
作者:Matthew P. Ball-Jones、Jasper Tyler、Helena Mora-Radó、Werngard Czechtizky、María Méndez、Joseph P. A. Harrity
DOI:10.1021/acs.orglett.9b02455
日期:2019.9.6
The greater geometric lability of hydrazones compared to that of oximeethers is used as a basis to overcome the reluctance of Z-oxime ether azatrienes to undergo electrocyclization toward the synthesis of borylated (heteroaromatic) pyridines and ring-fused analogues. Such hydrazones now allow access to previously inaccessible tri- and tetrasubstituted 3-borylpyridines in high yields.
A Strategy To Obtain <i>o</i>-Naphthoquinone Methides: Ag(I)-Catalyzed Cyclization of Enynones for the Synthesis of Benzo[<i>h</i>]chromanes and Naphthopyryliums
作者:Feng Wu、Shifa Zhu
DOI:10.1021/acs.orglett.9b00281
日期:2019.3.1
of 2-alkenylphenyl alkynyl ketones and its [4 + 2] annulations with styrenes has been developed. This reaction features high efficiency, mild reaction conditions, as well as flexible substitutions and atom economy. The obtained benzo[h]chromane products were further oxidized to naphthopyryliums, which displayed tunable photophysical properties.
已开发出一种通过Ag(I)催化2-烯基苯基炔基酮的环化反应及其[4 + 2]与苯乙烯的环化反应,通过成环策略获得o -NQM中间体的新策略。该反应具有高效,温和的反应条件,灵活的取代和原子经济性等特点。所获得的苯并[ h ]苯并二氢吡喃产物被进一步氧化成萘并具有可调节的光物理性质。
One-Pot Synthesis of Pyrimidines via Cyclocondensation of β-Bromovinyl Aldehydes with Amidine Hydrochlorides
作者:Shengjiao Yan、Yajuan Tang、Fuchao Yu、Jun Lin
DOI:10.1002/hlca.201000264
日期:2011.3
A series of pyrimidines were prepared by cyclocondensation of β‐bromovinyl aldehydes with amidinehydrochlorides in the presence of Et3N in excellent yields (74–95%).
Stereoselective One-Pot Sequential Dehydrochlorination/<i>trans</i>
-Hydrofluorination Reaction of β-Chloro-α,β-unsaturated Aldehydes or Ketones: Facile Access to (<i>Z</i>
)-β-Fluoro-β-arylenals/β-Fluoro-β-arylenones
作者:Jingli Zhang、Liran Liu、Junxin Duan、Lianghu Gu、Bifeng Chen、Taolei Sun、Yuefa Gong
DOI:10.1002/adsc.201700981
日期:2017.12.19
high potential as a fluorinated synthon in organic synthesis. However, control of the Z/E stereoselectivity of multi‐substituted monofluoroalkene products in one‐pot reactions still remains a challenge. An unprecedented one‐pot approach for the highly regio‐ and stereoselective preparation of functionalized (Z)‐β‐monofluoro tri‐substituted alkenesfrom readily available β‐chloro‐α,β‐unsaturated aldehydes