Gold(III)-Catalyzed Formal [3 + 2] Annulations of <i>N</i>-Acyl Sulfilimines with Ynamides for the Synthesis of 4-Aminooxazoles
作者:Xianhai Tian、Lina Song、Chunyu Han、Cheng Zhang、Yufeng Wu、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1021/acs.orglett.9b01011
日期:2019.4.19
A gold-catalyzed formal 1,3-dipolar [3 + 2] annulation using readily accessible N-acyl sulfilimines and ynamides is reported. This reaction includes the cleavage of a N–S bond and subsequent C–O bond formation. In total, 30 oxazole derivatives bearing diverse functionalities could be prepared in 43–98% yield from the corresponding sulfilimines and ynamides.
A novel method for the synthesis of α-amino alkenyl-substituted hydrazone derivatives was disclosed through silver-catalyzed reaction of sulfonyl hydrazones with ynamides. The present method features mild conditions, highstereoselectivity and good yields. The proposed mechanism involves silver-mediated generation of a keteniminium ion intermediate to facilitate the stereoselective addition of hydrazones
通过银催化磺酰与乙酰胺的反应,公开了一种合成α-氨基烯基取代的derivatives衍生物的新方法。本方法具有温和的条件,高的立体选择性和良好的收率。所提出的机理涉及银介导的酮亚胺离子中间体的产生,以促进在K 2 CO 3存在下立体选择性地添加,而在当前条件下不能构建吡唑环。
Copper-Catalyzed Aerobic Oxidative Amidation of Terminal Alkynes: Efficient Synthesis of Ynamides
作者:Tetsuya Hamada、Xuan Ye、Shannon S. Stahl
DOI:10.1021/ja077406x
日期:2008.1.1
A copper-catalyzed method for the preparation of ynamides has been identified that proceeds via aerobicoxidative coupling of terminal alkynes with various nitrogen nucleophiles, including cyclic carbamates, amides and ureas, and N-alkyl-arylsulfonamides and indoles.
Keteniminium‐Driven Umpolung Difunctionalization of Ynamides
作者:Shubham Dutta、Shengwen Yang、Rajeshwer Vanjari、Rajendra K. Mallick、Vincent Gandon、Akhila K. Sahoo
DOI:10.1002/anie.201915522
日期:2020.6.26
synthesis of novel triaryl‐substituted enamides is described. This transformation represents the first example of an umpolung regioselective unsymmetrical syn ‐1,2‐diarylation/aryl‐olefination of ynamides. The aryl moieties of the diazonium salt (electrophile) and boronic acid (nucleophile) are explicitly incorporated in the electrophilic α‐ and nucleophilic β‐position, respectively, of the ynamide
Synthesis of α-Fluorinated Imides via Direct Fluorohydroxylation of Ynamides
作者:Ji-Lin Li、E. Lin、Xiang-Lei Han、Qingjiang Li、Honggen Wang
DOI:10.1021/acs.orglett.9b01428
日期:2019.6.7
A practical synthesis of α-fluorinated imides via the catalyst-free fluorohydroxylation of ynamides is developed. The reaction employs commercially available Selectfluor (F-TEDA-BF4) and H2O as the fluorine and hydroxyl sources, respectively. A broad range of aryl- or alkyl-substituted ynamides were well applicable to the reaction with good functional group tolerance under simple and mild reaction