Ruthenium-Catalyzed Enantioselective Hydrogenation of Hydrazones
作者:Christopher H. Schuster、James F. Dropinski、Michael Shevlin、Hongming Li、Song Chen
DOI:10.1021/acs.orglett.0c02756
日期:2020.10.2
Prochiral hydrazones undergo efficient and highly selective hydrogenation in the presence of a chiral diphosphine ruthenium catalyst, yielding enantioenriched hydrazine products (up to 99% ee). The mild reaction conditions and broad functional group tolerance of this method allow access to versatile chiral hydrazine building blocks containing aryl bromide, heteroaryl, alkyl, cycloalkyl, and ester substituents
An asymmetric reductive amination of ketones using both arylamines and benzhydrazide in the presence of nickel catalysts was developed. A one‐pot synthesis of tetrahydroquinoxalines was also developed starting directly from α‐ketoaldehydes and 1,2‐diaminobenzene. Formic acid was used as a safe and economic surrogate for high‐pressure hydrogen gas. Strongly σ‐donating bis(alkylphosphine)s are crucial
Nickel-Catalyzed N-Alkylation of Acylhydrazines and Arylamines Using Alcohols and Enantioselective Examples
作者:Peng Yang、Caili Zhang、Yu Ma、Caiyun Zhang、Aijie Li、Bo Tang、Jianrong Steve Zhou
DOI:10.1002/anie.201708949
日期:2017.11.13
atom‐economic way to prepare alkylamines, ideally with water as the sole byproduct. Herein, nickel catalysts are used for direct N‐alkylation of hydrazides and arylamines using racemic alcohols. Moreover, a nickel catalyst of (S)‐binapine was used for an asymmetric N‐alkylation of benzohydrazide with racemic benzylic alcohols.
Chirale Diphosphinoterpene und deren Übergangsmetallkomplexe
申请人:LANXESS Deutschland GmbH
公开号:EP1595886A1
公开(公告)日:2005-11-16
Die vorliegende Erfindung betrifft chirale Diphosphinoterpene und deren Übergangsmetallkomplexe, ein Verfahren zur Herstellung chiraler Diphosphinoterpene bzw. deren Oxide und Übergangsmetallkomplexe enthaltend die chiralen Diphosphinoterpene. In einem weiteren Aspekt betrifft die Erfindung die Verwendung der chiralen Diphosphinoterpene bzw. deren Übergangsmetallkomplexe in asymmetrischen Synthesen.
Catalytic asymmetric reductive amination of ketones via highly enantioselective hydrogenation of the CN double bond
作者:Mark J. Burk、Jose P. Martinez、John E. Feaster、Nick Cosford
DOI:10.1016/s0040-4020(01)89375-3
日期:1994.4
a convenient, chemoselective asymmetric reductive amination procedure for the conversion of ketones to chiral hydrazines and amines. The key step in the three-step process is enantioselective DuPHOS-Rh-catalyzed hydrogenation of the CN double bond of N-acylhydrazones. Detailed optimization studies revealed the effect of solvent, temperature, and the N-acyl group on the enantioselectivity and catalytic