Single-Component Phosphinous Acid Ruthenium(II) Catalysts for Versatile C−H Activation by Metal-Ligand Cooperation
作者:Daniel Zell、Svenja Warratz、Dmitri Gelman、Simon J. Garden、Lutz Ackermann
DOI:10.1002/chem.201504851
日期:2016.1.22
Well‐defined ruthenium(II) phosphinousacid (PA) complexes enabled chemo‐, site‐, and diastereoselective C−H functionalization of arenes and alkenes with ample scope. The outstanding catalytic activity was reflected by catalyst loadings as low as 0.75 mol %, and the most step‐economical access reported to date to angiotensin II receptor antagonist blockbuster drugs. Mechanistic studies indicated a
methylheteroarenes (2-methylbenzothiophene, 2-methylbenzofuran, and 2-, 3-, or 4-methylpyridines) are used as nucleophiles. Application to enamine synthesis using DMF as an electrophile is also shown. The present system is effective for toluenes (4-phenyl-, 4-bromo-, 2-bromo-, and 4-chlorotoluenes) having lowreactivity.
Electrochemical Hydrogenation with Gaseous Ammonia
作者:Jin Li、Lingfeng He、Xu Liu、Xu Cheng、Guigen Li
DOI:10.1002/anie.201813464
日期:2019.2.4
serves as high‐energy‐density hydrogen‐storage material. It is important to develop new reactions able to utilize ammonia as a hydrogen source directly. Herein, we report an electrochemical hydrogenation of alkenes, alkynes, and ketones using ammonia as the hydrogen source and carbon electrodes. A variety of heterocycles and functional groups, including for example sulfide, benzyl, benzyl carbamate, and
Rhodium/N-Heterocyclic Carbene Catalyzed Direct Intermolecular Arylation of sp<sup>2</sup>and sp<sup>3</sup>CH Bonds with Chelation Assistance
作者:Min Kim、Jaesung Kwak、Sukbok Chang
DOI:10.1002/anie.200903500
日期:2009.11.9
chelation‐assisted direct intermolecular arylation using an N‐heterocyclic carbene and phosphine ligands (see scheme; IMes=1,3‐bis(2,4,6‐trimethylphenyl)imidazol‐2‐ylidene). The reaction is operationally simple, proceeds under mild reaction conditions to afford mono‐ or diarylated products in excellent yields, and is applicable to the arylation at the sp3 or sp2CH bonds of 2‐pyridyl‐containing aryl, vinyl