Green Synthesis of 3‐Alkylidenefuran‐2‐ones by Palladium‐Catalyzed Cyclocarbonylation of Aryl Iodides with Benzyl Acetylenes in 2‐MeTHF
作者:Jianan Zhan、Junmin Chen、Li Wei、Mingzhong Cai
DOI:10.1002/ejoc.202301152
日期:2024.1.22
A general, efficient and practical method for the synthesis of 3-alkylidenefuran-2-ones has been developed from readily accessible aryl iodides and benzyl acetylenes via a recyclable palladium-catalyzedcarbonylative coupling reaction in a green solvent 2-MeTHF. The reaction proceeds smoothly under a CO atmosphere and mild conditions, yielding a wide range of furanones in good to excellent yields.
通过在绿色溶剂 2-MeTHF 中进行可回收的钯催化的羰基化偶联反应,由易于获得的芳基碘和苄基乙炔开发了一种通用、有效且实用的合成 3-亚烷基呋喃-2-酮的方法。反应在 CO 气氛和温和条件下顺利进行,以良好到优异的收率产生各种呋喃酮。
Cu-Catalyzed C–H Trifluoromethylation of 3-Arylprop-1-ynes for the Selective Construction of Allenic Csp<sup>2</sup>–CF<sub>3</sub> and Propargyl Csp<sup>3</sup>–CF<sub>3</sub> Bonds
A new method has been developed for the Cu-catalyzed C-H trifluoromethylation of 3-arylprop-1-ynes for the selective construction of allenic Csp(2)-CF3 and propargyl Csp(3)-CF3 bonds. The selective formation of allenic Csp(2)-CF3 and propargyl Csp(3)-CF3 bonds can be controlled by modifying the reaction conditions.
Comparison of the electronic and steric structures of 1-vinyl-and 1-(prop-1-en-1-yl)pyrroles according to the 1H and 13C NMR data
作者:A. V. Afonin、I. A. Ushakov、D. E. Simonenko、O. A. Tarasova、M. A. Maksimova、B. A. Trofimov
DOI:10.1134/s1070428007030116
日期:2007.3
According to the H-1 and C-13 NMR data, 1-isopropenylpyrroles are characterized by larger dihedral angles between the heteroring and exocyclic double bond planes, as compared to isostructural 1-vinylpyrroles, due to steric effect of the alpha-methyl group in the propenyl fragment. As a result, p-pi conjugation with the propenyl group is weaker than with the vinyl group. The propenyl group in 1-isopropenylpyrrole having no other substituents in the heteroring is forced out from the heteroring plane, while the 1-vinylpyrrole molecule is planar. If substituents are present in positions 2 and 5 of the pyrrole ring, the propenyl group on the nitrogen atom becomes orthogonal with respect to the pyrrole ring plane, so that no p-pi conjugation is possible. The steric structures of (E)-1-(prop-1-en-1-yl)pyrrole and (Z)-1-(prop-l-en-l-yl)pyrrole are different: the propenyl group in the former is turned relative to the heteroring plane, while the latter molecule is planar.