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.
The [2+2] cycloaddition of ynamides with the highly polarized reagent Tf2C=CH2 has been developed to regioselectively afford bis(triflyl)aminocyclobutenes in the absence of catalyst under mild conditions. Incidentally, with the ynamides bearing electron‐rich aromatic rings at the C‐terminal, an interesting reactivity switch was observed; a cyclization/hydroxylation sequence yielded 2‐amino‐3‐(trif
酰胺与高极化试剂Tf 2 C = CH 2的[2 + 2]环加成已开发出在温和条件下在不存在催化剂的情况下区域选择性地提供双(三氟乙)氨基环丁烯的方法。顺便说一下,对于在C端带有富电子芳族环的炔基,观察到一个有趣的反应性开关。一个环化/羟基化序列产生2-氨基-3-(triflyl)环丁-2-烯醇。加有醇的氨基环丁烯结构导致通过环化/加氢烷氧基化过程形成氨基环丁烯基醚。此外,通过4个π电子环的制备α-氨基-β,γ-不饱和酮和3-(三氟乙烯)丁a-1,3-二烯-2-胺,证明了官能化的氨基环丁烯作为进一步精细加工的前体的效用。开环。
Aerobic oxidative alkynylation of H-phosphonates and amides: an efficient route for the synthesis of alkynylphosphonates and ynamides using a recyclable Cu–MnO catalyst
作者:Harshvardhan Singh、Tapan Sahoo、Chiranjit Sen、Sunil M. Galani、Subhash Chandra Ghosh
DOI:10.1039/c9cy00275h
日期:——
and efficient route for the synthesis of alkynylphosphonates and ynamides by aerobic oxidative alkynylation of H-phosphonates and amides with both aliphatic and aromatic alkynes using our synthesized recyclable heterogeneous Cu–MnO catalyst has been developed. The phosphorylation was carried out under base- and ligand-free conditions, and in the presence of air as the sole oxidant. The reaction is compatible
Chemo- and regioselective click reactions through nickel-catalyzed azide–alkyne cycloaddition
作者:Woo Gyum Kim、Seung-yeol Baek、Seo Yeong Jeong、Dongsik Nam、Ji Hwan Jeon、Wonyoung Choe、Mu-Hyun Baik、Sung You Hong
DOI:10.1039/d0ob00579g
日期:——
azide-alkyne cycloadditions from competing internal alkynes has been challenging. Herein, we report a nickel-catalyzed [3 + 2] cycloaddition of unsymmetrical alkynes with organic azides to afford functionalized 1,2,3-triazoles with excellent regio- and chemoselectivity control. Terminal alkynes and cyanoalkynes afford 1,5-disubstitutedtriazoles and 1,4,5-trisubstituted triazoles bearing a 4-cyano substituent
Radical Germylzincation of α-Heteroatom-Substituted Alkynes
作者:Karen de la Vega-Hernández、Elise Romain、Anais Coffinet、Kajetan Bijouard、Geoffrey Gontard、Fabrice Chemla、Franck Ferreira、Olivier Jackowski、Alejandro Perez-Luna
DOI:10.1021/jacs.8b09851
日期:2018.12.19
The regio- and stereoselectiveaddition of germanium and zinc across the C-C triple bond of nitrogen-, sulfur-, oxygen-, and phosphorus-substituted terminal and internal alkynes is achieved by reaction with a combination of R3GeH and Et2Zn. Diagnostic experiments support a radical-chain mechanism and the β-zincated vinylgermanes that show exceptional stability are characterized by NMR spectroscopy
通过与 R3GeH 和 Et2Zn 的组合反应,锗和锌在氮、硫、氧和磷取代的末端和内部炔烃的 CC 三键上的区域和立体选择性加成。诊断实验支持自由基链机制,并通过 NMR 光谱和 X 射线晶体学表征显示出异常稳定性的 β-锌化乙烯基锗烷。这种新的自由基锗基锌化反应的独特之处在于,形成的 C(sp2)-Zn 键仍然可用于随后的原位 Cu(I)-或 Pd(0)-介导的 CC 或 C-杂原子键的形成,同时保留双键几何。