Absolute Configuration of Lactams and Oxazolidinones Using Kinetic Resolution Catalysts
摘要:
A simple method for determining the absolute configuration of oxazolidinones, lactams, and their derivatives using kinetic resolution catalysts is described. The optically pure substrates were acylated using the (S)-HBTM and the (R)-HBTM catalyst, and the faster reaction was determined. An empirical mnemonic was developed for the assignment of the absolute configuration based on the fast-reacting catalyst.
Palladium-Catalyzed Enantioselective Relay Heck Arylation of Enelactams: Accessing α,β-Unsaturated δ-Lactams
作者:Qianjia Yuan、Matthew S. Sigman
DOI:10.1021/jacs.8b02752
日期:2018.5.30
In this Communication, we describe the construction of chiral α,β-unsaturated δ-lactams, widely used as pharmacophores, in high yields and excellent enantioselectivities using an oxidative relay Heckarylation reaction. This strategy also allows facile access to 7-substituted α,β-unsaturated ε-lactam products and δ-lactams containing a tetrasubstituted nitrogen-bearing stereocenter.
Asymmetric synthesis and applications of β-amino Weinreb amides: asymmetric synthesis of (S)-coniine
作者:Anthony J. Burke、Stephen G. Davies、A. Christopher Garner、Tom D. McCarthy、Paul M. Roberts、Andrew D. Smith、Humberto Rodriguez-Solla、Richard J. Vickers
DOI:10.1039/b402531h
日期:——
Conjugate addition of lithium (S)-N-benzyl-N-alpha-methylbenzylamide to a range of alpha, beta-unsaturated Weinreb amides proceeds with high levels of diastereoselectivity (>95% de). The beta-amino Weinreb amide products may be transformed into beta-amino ketones via reactions with Grignard reagents, while treatment with DIBAL-H furnishes beta-amino aldehydes. Trapping of the aldehyde via Wadsworth-Emmons
Synthesis of γ-, δ-, and ε-Lactams by Asymmetric Transfer Hydrogenation of <i>N</i>-(<i>tert</i>-Butylsulfinyl)iminoesters
作者:David Guijarro、Óscar Pablo、Miguel Yus
DOI:10.1021/jo400164y
日期:2013.4.19
Highly enantiomerically enriched γ- and δ-lactams have been prepared by a simple and very efficient procedure that involves the asymmetrictransferhydrogenation of N-(tert-butylsulfinyl)iminoesters followed by desulfinylation of the nitrogen atom and spontaneous cyclization to the desired lactams during the basic workup procedure. Five- and six-membered ring lactams bearing aromatic, heteroaromatic
Conversion of γ- and δ-Keto Esters into Optically Active Lactams. Transaminases in Cascade Processes
作者:Ángela Mourelle-Insua、Luiz Arthur Zampieri、Iván Lavandera、Vicente Gotor-Fernández
DOI:10.1002/adsc.201701304
日期:2018.2.15
biotransamination of ethyl or methyl keto esters bearing different alkyl or aryl substitution patterns at α‐position to the ketone functionality. In this manner, the keto esters were transformed into the corresponding amino esters with excellent conversions, which underwent spontaneous cyclisation in the reaction medium without addition of external reagents. Depending on the transaminase selectivity, both lactam
New P,N-Ferrocenyl Ligands for the Asymmetric Ir-Catalyzed Hydrogenation of Imines
作者:Murthy N. Cheemala、Paul Knochel
DOI:10.1021/ol071168t
日期:2007.8.1
The Ir-catalyzed enantioselective hydrogenation of various N-(3,5-dimethyl-4-methoxy)phenylimines was performed under mild conditions in the presence of new P,N-ferrocenyl iridium complexes leading to (R)-N-(3,5-dimethyl-4-methoxy)phenylamines in high yields and enantioselectivities (up to 99%). These chiral aryl amines can be readily deprotected using Ce(NH4)2(NO3)6.