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.
Chiral phosphoramidite–olefin hybrid ligands were found to be effective in the iridium-catalyzed asymmetric alkylation of N-arylbenzamides with vinyl ethers. The reaction is catalyzed by a hydroxoiridium catalyst coordinated with the hybrid ligand to give the corresponding products in high yields with high branch selectivity and enantioselectivity.
Rhodium(III)-Catalyzed C(sp<sup>2</sup>)–H Chemoselective Annulation to O-Cyclized Isochromen-imines from Benzamides
作者:Ping Zhang、Wenju Chang、Yan-Shang Kang、Wenxuan Zhao、Pei-Pei Cui、Yong Liang、Wei-Yin Sun、Yi Lu
DOI:10.1021/acs.orglett.0c03425
日期:2020.12.18
selective annulation of benzamides with internal alkynes has been achieved to the formation of O-cyclized isochromen-imines. Various substituents are well-tolerated under mild reaction conditions. Density functional theory calculations indicate that silver carbonate could act as a Lewis acid to assist the ligand to improve the chemical selectivity of the reaction in a catalyticsystem.
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