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。
Synthesis of highly substituted oxetanes via [2+2] cycloaddition reactions of allenoates catalyzed by a guanidine Lewis base
作者:Philipp Selig、Aleksej Turočkin、William Raven
DOI:10.1039/c3cc40855h
日期:——
The first synthesis of highly substituted 3-alkyl-oxetan-2-ylidenes from allenoates was developed by using the bicyclic guanidine 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as an exceptionally active nitrogen Lewis base catalyst.
Novel allene-acetylene cross-condensation catalyzed by palladium complexes
作者:Barry M. Trost、Georg Kottirsch
DOI:10.1021/ja00163a062
日期:1990.3
We report our preliminary results, in which we succeeded in achieving such a condensation with an unusual dependence of product regioselectivity on the choice of catalyst
我们报告了我们的初步结果,其中我们成功地实现了这种缩合,并且产物区域选择性异常依赖于催化剂的选择
Synthesis of 1,4-Enamino Ketones by [3,3]-Rearrangements of Dialkenylhydroxylamines
作者:Wiktoria H. Pecak、Jongwoo Son、Amy J. Burnstine、Laura L. Anderson
DOI:10.1021/ol501230e
日期:2014.7.3
4-enamino ketones has been achieved through the [3,3]-rearrangement of dialkenylhydroxylamines generated from the addition of N-alkenylnitrones to electron-deficient allenes. The mild conditions required for this reaction, and the simultaneous installation of a fluorenyl imine N-protecting group as a consequence of the rearrangement, avoid spontaneous cyclization of the 1,4-enamino ketones to form the
Enantioselective γ‐Addition of Pyrazole and Imidazole Heterocycles to Allenoates Catalyzed by Chiral Phosphine
作者:Haiyang Wang、Chang Guo
DOI:10.1002/anie.201813381
日期:2019.2.25
catalyze the enantioselective asymmetric γ‐addition of heteroaromatic compounds to allenoates in good yields with high enantiomeric ratios and regioselectivity in the presence of (S)‐BINOL. Both pyrazole and imidazole could be employed in this process. The synthetic value of these γ‐addition products was demonstrated by the preparation of biologically relevant molecules and structural scaffolds. Remarkably