Preparation of Chiral Allenes through Pd-Catalyzed Intermolecular Hydroamination of Conjugated Enynes: Enantioselective Synthesis Enabled by Catalyst Design
作者:Nathan J. Adamson、Haleh Jeddi、Steven J. Malcolmson
DOI:10.1021/jacs.9b02637
日期:2019.5.29
surrogate to afford primary amines in a two-step/one-pot process. Examination of chiral catalysts revealed a high degree of reversibility in the C-N bond formation that negatively impacted enantioselectivity. Consequently, an electron-poor ferrocenyl-PHOX ligand was developed to enable efficient and enantioselective enyne hydroamination.
A gold catalyzed formal intermolecular [2+3] cyclo-coupling of 1,3-enynes with phenols was developed to prepare dihydrobenzofuran derivatives with the addition of 2,6-dichloropyridine N-oxide, in which, a highly ortho-selective phenol SEAr functionalization was achieved by using 1,3-enynes as α-oxo vinyl gold carbenoid surrogates.
开发了金催化的 1,3-烯炔与苯酚的正式分子间 [2+3] 环偶联,通过添加 2,6-二氯吡啶N-氧化物制备二氢苯并呋喃衍生物,其中,高度邻位选择性的苯酚 S E Ar 官能化是通过使用 1,3-烯炔作为 α-氧代乙烯基金卡宾酸替代物来实现的。
A radical-mediated 1,3,4-trifunctionalization cascade of 1,3-enynes with sulfinates and <i>tert</i>-butyl nitrite: facile access to sulfonyl isoxazoles
作者:Xin Yue、Ming Hu、Xingyi He、Shuang Wu、Jin-Heng Li
DOI:10.1039/d0cc01659d
日期:——
indium-promoted three-component 1,3,4-trifunctionalization cascade of 1,3-enynes with sodium sulfinates and tert-butyl nitrite (TBN) to access 5-sulfonylisoxazoles via [3+2] annulation is reported. By employing TBN as both the radical initiator and the N–O two atom unit, this method enables the formation of three new carbon–heteroatom bonds, C–S, C–N and C–Obonds, in a single reactionthrough a sequence
Cobalt-Catalyzed gem-Cross-Dimerization of Terminal Alkynes
作者:Jia-Feng Chen、Changkun Li
DOI:10.1021/acscatal.9b05078
日期:2020.3.20
Transition-metal-catalyzed dimerization of two different terminalalkynes provides an atom-economic synthesis of valuable conjugated 1,3-enynes. Despite many catalyst systems developed, the state-of-the-art solutions are still limited to special alkynes. A practical catalyst, which could be used to cross-dimerize general aryl alkynes and aliphatic alkynes, is still highly desired. Herein we present
Regioselective Access to 3‐Ethylideneflavanones via Rhodium(I)‐Catalyzed 1,3‐Enyne Hydroacylation/Annulation Cascades
作者:Zhi‐Xin Chang、Fu‐Rong Li、Chengcai Xia、Fei Li、Hong‐Shuang Li
DOI:10.1002/adsc.202001565
日期:2021.3.16
The highly efficient synthesis of 3‐ethylideneflavanones throughsequential rhodium(I)‐catalyzed hydroacylation of terminal aryl‐substituted 1,3‐enynes with chelating aldehydes and annulation is described. This straightforward protocol highlights an unprecedented C3‐regioselective hydroacylation of 1,3‐enynes, excellent functional group compatibility, and complete atom economy.