Electrophilic Cyclization of o-Anisole- and o-Thioanisole-Substituted Ynamides: Synthesis of 2-Amidobenzofurans and 2-Amidobenzothiophenes
摘要:
A facile synthesis of 3-substituted 2-amidobenzofurans and 2-amidobenzothiophenes via electrophilic cyclization reaction of o-anisole- and o-thioanisole-substituted ynamides with I-2, NBS and NCS was developed. The products 3-iodo-2-amidobenzofurans were further transferred into 3-aryl-, 3-alkynyl, and 3-vinyl-2-amidobenzofurans via Pd-catalyzed reactions such as Suzuki-Miyaura and Sonogashira cross-coupling reactions and the Heck reaction.
Synthesis of 3-Alkyl- or 3-Allenyl-2-amidobenzofurans via Electrophilic Cyclization of <i>o</i>-Anisole-Substituted Ynamides with Carbocations
作者:Yulong Kong、Kezhi Jiang、Jian Cao、Lingzi Fu、Lian Yu、Guoqiao Lai、Yuming Cui、Ziqiang Hu、Guanhai Wang
DOI:10.1021/ol303474a
日期:2013.1.18
A facile carbocation-induced electrophilic cyclization reaction has been developed for the synthesis of 3-alkyl- or 3-allenyl-2-amidobenzofurans from o-anisole-substituted ynamides and diarylmethanol or 1,1-diarylprop-2-yn-1-ol.
Gold-Catalyzed <i>syn</i>-1,2-Difunctionalization of Ynamides via Nitrile Activation
作者:Rajeshwer Vanjari、Shubham Dutta、Manash P. Gogoi、Vincent Gandon、Akhila K. Sahoo
DOI:10.1021/acs.orglett.8b03830
日期:2018.12.21
Developed is an unprecedented Au(I)-catalyzed syn-1,2-difunctionalization of ynamides with 2-aminobenzonitriles via nitrile activation. The coupling between ynamides and 2-aminobenzonitriles is explicitly regioselective, providing a straightforward access to 2,4-diamino-substituted quinolines. Density functional theory (DFT) study provides insightful information and rationalizes the reaction pathway
The synthesis of ynamides in water was achieved by a micellarcatalysis strategy using rosin‐based surfactant APGS‐550‐M, which can be easily prepared from natural abundant biomass.
Copper-Mediated Selective Cross-Coupling of 1,1-Dibromo-1-alkenes and Heteronucleophiles: Development of General Routes to Heterosubstituted Alkynes and Alkenes
site-selective, double, or alkynylative cross-coupling, therefore providing divergent and straightforward entries to numerous building blocks such as bromoenamides, ynamides, ketene N,N-acetals, bromoenol ethers, ynol ethers, keteneO,O-acetals, or vinylphosphonates and further expanding the copper catalysis toolbox with useful and versatile processes.
Synthesis of Amide Enol Carbamates and Carbonates through Cu(OTf)<sub>2</sub>-Catalyzed Reactions of Ynamides with <i>t</i>-Butyl Carbamates/Carbonates
作者:Pan Han、Zhuo-Ya Mao、Ming Li、Chang-Mei Si、Bang-Guo Wei、Guo-Qiang Lin
DOI:10.1021/acs.joc.9b03512
日期:2020.4.3
A highly regioselective approach to access amide enol carbamates and carbonates 5a–5c′, 7a–7h, and 9 was developed through Cu(OTf)2-catalyzed reactions of ynamides 4 with t-butyl carbamates 2 and 8 and t-butyl carbonates 6. Moreover, this strategy was successfully applied to generate amide enol carbamates 11a–11s and 14a–14f from imides 10 and 13 with ynamides through an N-Boc cleavage–addition ring-opening