Phosphine catalyzed [3+2] cyclization/Michael addition of allenoate with CS<sub>2</sub> to form 2-thineyl vinyl sulfide
作者:Weihong Fei、Ping Xu、Jie Hou、Weijun Yao
DOI:10.1039/d0cc05070a
日期:——
have developed a DPPE-catalyzed three molecular two component tandem reaction of γ-substituted allenoate and CS2 to construct 2-thineyl vinyl sulfide through phosphine catalyzed [3+2] cyclization followed by Michaeladdition. The synthetic value of the 2-thineyl vinyl sulfide was demonstrated by a concise synthesis of an anti-glaucoma agent.
Nickel(II)-Catalyzed [3 + 2] Cycloaddition of Nitrones and Allenoates to Access <i>N</i>-Vinylindoles and <i>N</i>-Vinylpyrroles
作者:Pei-Pei Xu、Jun-Yi Liao、Jia-Jie Zhang、Wei-Min Shi、Cui Liang、Gui-Fa Su、Dong-Liang Mo
DOI:10.1021/acs.orglett.1c02695
日期:2021.10.1
A variety of N-vinylindoles and N-vinylpyrroles were prepared in moderate to good yields through the nickel(II)-catalyzed [3 + 2] cycloaddition of α,β-unsaturated nitrones with allenoates under mild reaction conditions. A rational mechanism for the formation of N-vinylindoles was proposed based on the 18O-labeled experiments and key intermediates detected by high-resolution mass spectrometry trace
在温和的反应条件下,通过镍 (II) 催化的 α,β-不饱和硝酮与烯丙酸酯的 [3 + 2] 环加成反应,以中等至良好的收率制备了多种N-乙烯基吲哚和N-乙烯基吡咯。基于18个O标记实验和高分辨率质谱痕量实验检测到的关键中间体,提出了N-乙烯基吲哚形成的合理机制。本方法突出了镍 (II) 控制的环化、原子经济反应、广泛的底物范围、良好的官能团耐受性和烯胺键的高 Z 立体选择性。
Phosphine-mediated Highly Enantioselective Spirocyclization with Ketimines as Substrates
作者:Xiaoyu Han、Wai-Lun Chan、Weijun Yao、Yongjiang Wang、Yixin Lu
DOI:10.1002/anie.201600453
日期:2016.5.23
Phosphine‐catalyzed enantioselectiveannulation reactions involving ketimines are a daunting synthetic challenge owing to the intrinsic low reactivity of ketimine substrates. A highly enantioselective [3+2] cycloaddition reaction that makes use of isatin‐derived ketimines as reaction partners was developed. Notably, both simple and γ‐substituted allenoates could be utilized, and various 3,2′‐pyrrolidinyl
Reactivity of allenoates towards aziridines: synthesis of functionalized methylenepyrrolidines and pyrroles
作者:Fernanda M. Ribeiro Laia、Ana Lúcia Cardoso、Ana Matos Beja、Manuela Ramos Silva、Teresa M.V.D. Pinho e Melo
DOI:10.1016/j.tet.2010.09.081
日期:2010.11
The reactivity of buta-2,3-dienoates towards aziridines is reported. Typically, allenoates react as the 2π-component in the [3+2] cycloaddition with azomethine ylides generated from aziridines, affording 4-methylenepyrrolidines in a site-, regio- and stereoselective fashion. However, N-cyclohexyl- or N-tert-butyl-2-benzoyl-3-phenylaziridines showed a different reactivity in the reaction with buta-2
Reactivity of allenoates toward aziridines: [3+2] and formal [3+2] cycloadditions
作者:Fernanda M. Ribeiro Laia、Teresa M.V.D. Pinho e Melo
DOI:10.1016/j.tetlet.2009.08.088
日期:2009.11
reported. Allenoates react as 2π-component in the [3+2] cycloaddition with the azomethine ylide generated from cis-1-benzyl-2-benzoyl-3-phenylaziridine affording 4-methylenepyrrolidines in a site-, regio-, and stereoselective fashion. Under conventional thermolysis, cis- and trans-2-benzoyl-1-cyclohexyl-3-phenylaziridines showed a different reactivity. These aziridines participate in formal [3+2] cycloadditions