844851-97-4Relevant academic research and scientific papers
Cationic NHC-Phosphine Iridium Complexes: Highly Active Catalysts for Base-Free Hydrogenation of Ketones
Quan, Xu,Kerdphon, Sutthichat,Peters, Bram B. C.,Rujirawanich, Janjira,Krajangsri, Suppachai,Jongcharoenkamol, Jira,Andersson, Pher G.
supporting information, p. 13311 - 13316 (2020/09/22)
Novel bidentate N-heterocyclic carbene-phosphine iridium complexes have been synthesized and evaluated in the hydrogenation of ketones. Reported catalytic systems require base additives and, if excluded, need elevated temperature or high pressure of hydrogen gas to achieve satisfactory reactivity. The developed catalysts showed extremely high reactivity and good enantioselectivity under base-free and mild conditions. In the presence of 1 mol % catalyst under 1 bar hydrogen pressure at room temperature, hydrogenation was complete in 30 minutes giving up to 96 % ee. Again, this high reactivity was achieved in additive-free conditions. Mechanistic experiments demonstrated that balloon pressure of hydrogen was sufficient to form the activate species by reducing and eliminating the 1,5-cyclooctadiene ligand. The pre-activated catalyst was able to hydrogenate acetophenone with 89 % conversion in 5 min.
FUSED-RING OR TRICYCLIC ARYL PYRIMIDINE COMPOUND USED AS KINASE INHIBITOR
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, (2018/03/25)
Disclosed is a fused-ring or tricyclic aryl pyrimidine compound used as a mutation selectivity EGFR inhibitor. Specifically, disclosed is a compound represented by formula (I) and used as an EGFR inhibitor or a pharmaceutically acceptable salt thereof.
Chiral phosphino- and (phosphinooxy)-substituted N-heterocyclic carbene ligands and their application in indium-catalyzed asymmetric hydrogenation
Nanchen, Steve,Pfaltz, Andreas
, p. 1559 - 1573 (2007/10/03)
Enantiomerically pure iridium complexes with phosphino- and (phosphinooxy)-substituted N-heterocyclic carbene (NHC) ligands were synthesized. Investigation of their electronic properties showed a similar trans influence of the phosphino (or phosphinooxy) and the NHC units. The complexes were tested in iridium-catalyzed hydrogenation. While low conversions were observed with unfunctionalized olefins, the catalysts proved to be suitable for hydrogenation of the α,β-unsaturated ester 20, allylic alcohol 21, and imine 22. The enantioselectivities were, however, moderate.
