Asymmetric Synthesis of Chiral Primary Amines by Ruthenium-Catalyzed Direct Reductive Amination of Alkyl Aryl Ketones with Ammonium Salts and Molecular H<sub>2</sub>
amination of simple ketones. The strategy makes use of ammonium acetate as the amine source and H2 as the reductant and is a user-friendly and operatively simple access to industrially relevant primary amines. Excellent enantiocontrol (>90% ee for most cases) was achieved with a wide range of alkylarylketones. The practicability of this methodology has been highlighted by scalable synthesis of key intermediates
Chiral diphosphine ligands based on camphor: synthesis and applications in asymmetric hydrogenations
作者:Renat Kadyrov、Ilyas Z. Ilaldinov、Juan Almena、Axel Monsees、Thomas H. Riermeier
DOI:10.1016/j.tetlet.2005.08.103
日期:2005.10
The synthesis of a novel class of atropisomer chiral diphosphineligands with a bornene framework is described. The new ligands showed in Rh catalyzed asymmetric hydrogenation of α- and β-enamides very high ee’s (more than 99%).
Biocatalytic, Intermolecular C−H Bond Functionalization for the Synthesis of Enantioenriched Amides
作者:Soumitra V. Athavale、Shilong Gao、Zhen Liu、Sharath Chandra Mallojjala、Jennifer S. Hirschi、Frances H. Arnold
DOI:10.1002/anie.202110873
日期:2021.11.15
P411 heme enzymes enables intermolecular C−H amidation with high yields and exquisite enantioselectivity. The biocatalytic process utilizes stable hydroxamate esters as nitrenoid precursors and is amenable to scaleup. Mechanistic studies reveal rate-determining nitrenoid formation followed by a stepwise, hydrogen atom transfer-mediated C−Hfunctionalization.
Practical by Ligand Design: A New Class of Monodentate Phosphoramidite Ligands for Rhodium-Catalyzed Enantioselective Hydrogenations
作者:Baoguo Zhao、Zheng Wang、Kuiling Ding
DOI:10.1002/adsc.200606013
日期:2006.6
new class of low-cost and easy-to-prepare monodentate phosphoramidite ligands (CydamPhos) has been developed from readily accessible and cheap trans-1,2-diaminocyclohexane as starting material through a three-step transformation. This type of ligands exhibited excellent enantioseletivities and high activities in rhodium(I)-catalyzed asymmetric hydrogenations of dehydro-α-amino acid methyl esters 9 (ee:
Six-membered bis(azaphosphorinane), readily available ligand for highly enantioselective asymmetric hydrogenations
作者:Yongjun Yan、Xumu Zhang
DOI:10.1016/j.tetlet.2006.01.003
日期:2006.3
A new six-membered bis(azaphosphorinane) ligand has been readily prepared starting from an inexpensive chiral epoxide; excellent enantioselectivities (up to over 99% ee) have been achieved in the Rh-catalyzed asymmetric hydrogenations of β-dehydroamino acid derivatives and α-arylenamides.