Synthesis and Characterization of Alkyllanthanum Biphenolate Complexes as Catalysts for Hydroamination/Cyclization and Hydrosilylation
作者:Denis V. Gribkov、Frank Hampel、Kai C. Hultzsch
DOI:10.1002/ejic.200400265
日期:2004.10
phenolate groups of the biphenolate ligands. The two different phenolate groups undergo an intramolecular exchange process in solution leading to their equivalence on the NMR timescale. The biphenolate alkyl complex shows high catalytic activity for hydroamination/cyclization of aminoalkenes, similar to previously known lanthanocene catalysts, but only low enantioselectivity. Addition of THF to [La(R)-Biphen}CH(SiMe3)2}]2
Chelating Bis(thiophosphinic amidate)s as Versatile Supporting Ligands for the Group 3 Metals. An Application to the Synthesis of Highly Active Catalysts for Intramolecular Alkene Hydroamination
Bis(thiophosphinic amidate) complexes (i.e., 1) of representative group 3 and lanthanide metals have been quantiatively prepared in situ from the corresponding thiophosphinic amides and Ln[N(TMS)2]3. These unusual pentacoordinate complexes exhibit very high activity as catalysts for intramolecular alkene hydroamination.
Iron-Catalyzed Synthesis of α-Dienyl Five- and Six-Membered N-Heterocycles
作者:Laurine Gonnard、Amandine Guérinot、Janine Cossy
DOI:10.1002/ejoc.201700977
日期:2017.11.9
The iron‐catalyzed synthesis of α‐dienyl N‐heterocycles is reported. The method is cost‐effective, atom‐economic, and led to a range of substituted α‐dienyl heterocycles in moderate to good yields and diastereoselectivities. The α‐dienyl piperidines are key synthetic intermediates as demonstrated by the preparation of a panel of α‐polyenyl N‐heterocycles.
FeCl<sub>3</sub>-Catalyzed Highly Diastereoselective Synthesis of Substituted Piperidines and Tetrahydropyrans
The eco-friendly and highly diastereoselective synthesis of substituted cis-2,6-piperidines and cis-2,6-tetrahydropyrans is described. The key step of this method is the iron-catalyzed thermodynamic equilibration of 2-alkenyl 6-substituted piperidines and 2-alkenyl 6-substituted tetrahydropyrans allowing the isolation of enriched mixtures of the most stable cis-isomers.
PROCESSES AND INTERMEDIATES FOR PREPARING A MACROCYCLIC PROTEASE INHIBITOR OF HCV