Metal–Ligand Cooperation Facilitates Bond Activation and Catalytic Hydrogenation with Zinc Pincer Complexes
作者:Michael Rauch、Sayan Kar、Amit Kumar、Liat Avram、Linda J. W. Shimon、David Milstein
DOI:10.1021/jacs.0c05500
日期:2020.8.26
A series of PNP zinc pincer complexes capable of bondactivation via aromatization/dearomatization metal–ligand cooperation (MLC) were prepared and characterized. Reversible heterolytic N–H and H–H bondactivation by MLC is shown, in which hemilability of the phosphorus linkers plays a key role. Utilizing this zinc pincer system, base-free catalytic hydrogenation of imines and ketones is demonstrated
Magnesium-Promoted Additions of Difluoroenolates to Unactivated Imines
作者:Alex L. Nguyen、Hari R. Khatri、James R. Woods、Cassidy S. Baldwin、Frank R. Fronczek、David A. Colby
DOI:10.1021/acs.joc.7b03014
日期:2018.3.16
produce fluorinated and trifluoromethylated organic structures, the construction of difluoromethylated compounds remains a synthetic challenge. We have discovered that unactivated imines will react with difluoroenolates under exceedingly mild conditions when using magnesium salts and organic bases. We have applied this approach to the iminoaldol reaction to produce difluoromethylene groups as α,α-dif
The preparation of new Ru(II) complexes incorporating fac-coordinated lutidine-derived CNC ligands is reported. These derivatives are selectively deprotonated by tBuOK at one of the methylene arms of the pincer, leading to catalytically active species in the hydrogenation of imines.
Ruthenium(II) Complexes Containing Lutidine-Derived Pincer CNC Ligands: Synthesis, Structure, and Catalytic Hydrogenation of CN bonds
作者:Martín Hernández-Juárez、Joaquín López-Serrano、Patricia Lara、Judith P. Morales-Cerón、Mónica Vaquero、Eleuterio Álvarez、Verónica Salazar、Andrés Suárez
DOI:10.1002/chem.201406040
日期:2015.5.11
transmetalation with the corresponding silver‐carbene derivatives. Characterization of these derivatives shows both mer and fac coordination of the CNC ligands depending on the wingtips of the N‐heterocycliccarbene fragments. In the presence of tBuOK, the Ru‐CNC complexes are active in the hydrogenation of a series of imines. In addition, these complexes catalyze the reversible hydrogenation of phenantridine. Detailed