Ligand‐Promoted Rh
<sup>III</sup>
‐Catalyzed Thiolation of Benzamides with a Broad Disulfide Scope
作者:Yan‐Shang Kang、Ping Zhang、Min‐Yan Li、You‐Ke Chen、Hua‐Jin Xu、Jing Zhao、Wei‐Yin Sun、Jin‐Quan Yu、Yi Lu
DOI:10.1002/anie.201903511
日期:2019.7
A ligand‐promoted RhIII‐catalyzed C(sp2)−H activation/thiolation of benzamides has been developed. Using bidentate mono‐N‐protected amino acid ligands led to the first example of RhIII‐catalyzed aryl thiolation reactions directed by weakly coordinating directing amide groups. The reaction tolerates a broad range of amides and disulfide reagents.
Selective radical amination of aldehydic C(sp<sup>2</sup>)–H bonds with fluoroaryl azides via Co(<scp>ii</scp>)-based metalloradical catalysis: synthesis of N-fluoroaryl amides from aldehydes under neutral and nonoxidative conditions
作者:Li-Mei Jin、Hongjian Lu、Yuan Cui、Christopher L. Lizardi、Thiago N. Arzua、Lukasz Wojtas、Xin Cui、X. Peter Zhang
DOI:10.1039/c4sc00697f
日期:——
proven to be an effective metalloradical catalyst for intermolecularamination of C(sp2)–H bonds of aldehydes with fluoroaryl azides. The [Co(P1)]-catalyzed process can employ aldehydes as the limiting reagents and operate under neutral and nonoxidative conditions, generating nitrogen gas as the only byproduct. The metalloradical aldehydic C–H amination is suitable for different combinations of aldehydes
D 2h对称酰胺卟啉 3,5-Di t Bu-IbuPhyrin [Co( P1 )]的 Co( II ) 配合物已被证明是一种有效的金属基催化剂,用于 C(sp 2 )–H 键的分子间胺化醛与氟芳基叠氮化物。[Co( P1 )]-催化过程可以使用醛作为限制试剂并在中性和非氧化条件下运行,产生氮气作为唯一的副产品。金属基醛 C-H 胺化适用于醛和氟芳基叠氮化物的不同组合,产生相应的N-氟芳基酰胺的产率非常好。一系列机理研究支持 Co( II ) 催化的分子间 C-H 胺化的逐步自由基机制。
Rh(<scp>iii</scp>)-catalyzed C–H olefination of N-pentafluoroaryl benzamides using air as the sole oxidant
作者:Yi Lu、Huai-Wei Wang、Jillian E. Spangler、Kai Chen、Pei-Pei Cui、Yue Zhao、Wei-Yin Sun、Jin-Quan Yu
DOI:10.1039/c4sc03350g
日期:——
The oxidative olefination of a broad array of arenes and heteroarenes with a variety of activated and unactivated olefins has be achieved via a rhodium(III)-catalyzed C–H activation reaction. The use of an N-pentafluorophenyl benzamide directinggroup is crucial for achieving catalytic turnovers in the presence of air as the sole oxidant without using a co-oxidant.
Ligand development for rhodium(III)‐catalyzed C−Hactivation reactions has largely been limited to cyclopentadienyl (Cp) based scaffolds. 2‐Methylquinoline has now been identified as a feasible ligand that can coordinate to the metal center of Cp*RhCl to accelerate the cleavage of the C−H bond of N‐pentafluorophenylbenzamides, providing a new structural lead for ligand design. The compatibility of
compounds. The conformational ratio of these compounds in solution was correlated linearly with Hammett’s σp value of the substituent on the anilide ring, reflecting the repulsive interaction between the carbonyl group and the electron-rich aryl group. The addition of acid into the solution of 6, bearing pentafluorobenzoyl group, switched the stable amide conformation. In addition, the sizeable rotational
基于酰胺的分子开关在结构多样性上有其局限性。在这项工作中,我们设计并合成了一系列基于五氟苯甲酰基的苯甲酰苯胺化合物。这些化合物在溶液中的构象比与苯胺环上取代基的Hammett σ p值线性相关,反映了羰基和富电子芳基之间的排斥相互作用。在带有五氟苯甲酰基的6溶液中加入酸,改变了稳定的酰胺构象。此外,由五氟苯甲酰基部分诱导的6的相当大的旋转屏障使我们能够通过1 H NMR 光谱监测构象转变。