Copper-Catalyzed Vinylogous Aerobic Oxidation of Unsaturated Compounds with Air
作者:Hai-Jun Zhang、Alexander W. Schuppe、Shi-Tao Pan、Jin-Xiang Chen、Bo-Ran Wang、Timothy R. Newhouse、Liang Yin
DOI:10.1021/jacs.8b01886
日期:2018.4.18
A mild and operationally simple copper-catalyzed vinylogous aerobic oxidation of β,γ- and α,β-unsaturated esters is described. This method features good yields, broad substrate scope, excellent chemo- and regioselectivity, and good functional group tolerance. This method is additionally capable of oxidizing β,γ- and α,β-unsaturated aldehydes, ketones, amides, nitriles, and sulfones. Furthermore, the
描述了一种温和且操作简单的铜催化乙烯基有氧氧化 β,γ-和 α,β-不饱和酯。该方法具有收率好、底物范围广、化学选择性和区域选择性好、官能团耐受性好等特点。该方法还能够氧化β,γ-和α,β-不饱和醛、酮、酰胺、腈和砜。此外,本催化体系适用于双乙烯基和三乙烯基氧化。发现四甲基胍 (TMG) 作为碱的作用至关重要,但我们也推测它可以作为三氟甲磺酸铜 (II) 的配体来生产活性铜 (II) 催化剂。进行的机械实验表明,通过烯丙基铜 (II) 物质存在一个合理的反应途径。最后,
Palladium-Catalyzed Allenamide Carbopalladation/Allylation with Active Methine Compounds
作者:Xiaoyi Zhu、Ruibo Li、Hequan Yao、Aijun Lin
DOI:10.1021/acs.orglett.1c01369
日期:2021.6.18
carbopalladation/allylation with active methine compounds has been developed. Various indoles and isoquinolinones bearing a quaternary carbon center were achieved with good efficiency, a broad substrate scope and good functional group tolerance. This reaction underwent cascade oxidative addition, carbopalladation, and allylicalkylation, and two new C–C bonds were formed in one pot.
作者:Subir Goswami、Kenichi Harada、Mohamed F. El‐Mansy、Rajinikanth Lingampally、Rich G. Carter
DOI:10.1002/anie.201805370
日期:2018.7.16
The efficient, 12–14 step (LLS) total synthesis of (−)‐halenaquinone has been achieved. Key steps in the synthetic sequence include: (a) proline sulfonamide‐catalyzed, Yamada–Otani reaction to establish the C6 all‐carbon quaternary stereocenter, (b) multiple, novel palladium‐mediated oxidative cyclizations to introduce the furan moiety, and (c) oxidative Bergman cyclization to form the final quinone
Pummerer Cyclization Revisited: Unraveling of Acyl Oxonium Ion and Vinyl Sulfide Pathways
作者:Xin Li、Rich G. Carter
DOI:10.1021/acs.orglett.8b02059
日期:2018.9.21
Two viable pathways (vinyl sulfide and acyl oxoniumion) for the Pummerer cyclization have been unraveled that expand the reaction scope and capabilities. Use of Brønsted-enhanced Lewis acidity was key to realization of the vinyl sulfide pathway, whereas selective complexation of the sulfur lone pair facilitated the unprecedented acyl oxoniumion pathway. Preliminary mechanistic investigations support