214288-76-3Relevant academic research and scientific papers
Palladium-catalyzed diastereoselective synthesis of β,β-diarylpropionic acid derivatives and its application to the total synthesis of (R)-tolterodine and the enantiomer of a key intermediate for MK-8718
Zhi, Wubin,Li, Jingya,Zou, Dapeng,Wu, Yangjie,Wu, Yusheng
supporting information, p. 537 - 540 (2018/01/17)
Palladium-catalyzed diastereoselective synthesis of optically active β,β-diarylpropionic acid derivatives employing 4-(tert-butyl)oxazolidin-2-one as the chiral auxiliary under an air atmosphere in excellent yields with high diastereoselectivity is reported. The catalytic system is applied to the total synthesis of (R)-tolterodine and the enantiomer of a key intermediate for MK-8718.
Diastereoselective ru-catalyzed cross-metathesis-dihydroxylation sequence. An efficient approach toward enantiomerically enriched syn-diols
Neisius, N. Matthias,Plietker, Bernd
, p. 3218 - 3227 (2008/09/19)
(Chemical Equation Presented) Sequential catalysis has evolved as a powerful concept within the past years and allows the more efficient use of catalytically active expensive transition metals in organic synthesis. In this paper we present the stereoselective cross-metathesis-dihydroxylation of various olefins with chiral auxiliary substituted acrylamides. The chiral information (i.e., the auxiliary) introduced in the metathesis reactions allows for a stereoselective subsequent RuO4-catalyzed dihydroxylation. The sequence is concluded by an unusual kinetic resolution of the diastereomeric diols obtained in the oxidation reaction. As a consequence a variety of structurally diverse enantiomerically enriched diols are obtained. To the best of our knowledge the results summarized in this paper represent the first highly efficient diastereoselective RuO4-catalyzed oxidation.
SuperQuat 5,5-dimethyl-4-iso-propyloxazolidin-2-one as a mimic of Evans 4-tert-butyloxazolidin-2-one
Bull, Steven D.,Davies, Stephen G.,Garner, A. Christopher,Kruchinin, Dennis,Key, Min-Suk,Roberts, Paul M.,Savory, Edward D.,Smith, Andrew D.,Thomson, James E.
, p. 2945 - 2964 (2008/02/09)
The incorporation of a gem-dimethyl group at the 5-position of a chiral oxazolidinone biases the conformation of the adjacent C(4)-stereodirecting group such that the gem-dimethyl-4-iso-propyl combination mimics a C(4)-tert-butyl group, providing higher levels of stereocontrol than a simple 4-iso-propyloxazolidinone. The generality of this principle is demonstrated with applications in stereoselective enolate alkylations, kinetic resolutions, Diels-Alder cycloadditions and Pd-catalysed asymmetric acetalisation reactions. The Royal Society of Chemistry 2006.
Highly diastereoselective conjugate additions of monoorganocopper reagents to chiral imides
Dambacher, Jesse,Anness, Robert,Pollock, Patrick,Bergdahl, Mikael
, p. 2097 - 2110 (2007/10/03)
Stereoselective conjugate additions to chiral N-enoyl amides employing various monoorganocuprate reagents, Li[RCuI], are described. The presence of TMSI in the addition of Li[RCuI] in THF provided the highest stereoselectivities. Reversed major diastereom
trans-3,4-Disubstituted pyrrolidines by 1,3-dipolar cycloaddition: Enantioselective approaches and their limitations
Karlsson, Staffan,Han, Fusen,Hoegberg, Hans-Erik,Caldirola, Patrizia
, p. 2605 - 2616 (2007/10/03)
In the presence of a chiral Lewis acid as co-catalyst, the acid- catalysed 1,3-dipolar cycloaddition reaction yielding trans-3,4-disubstituted pyrrolidines from an azomethine ylide and achiral α,β-unsaturated dipolarophiles proceeded with low enantioselectivity. Therefore a number of α,β-unsaturated dipolarophiles linked to chiral auxiliaries were examined as substrates. Camphorsultam was the best auxiliary and gave good diastereoselectivity (dr=74:26). When combining chiral Lewis acids with a dipolarophile linked to a chiral auxiliary, the enantio-selectivity could be slightly increased. As judged by 13C NMR, the small effect of the chiral Lewis acids on selectivity was probably due to breakdown of the initially formed complex with the dipolarophile caused by the dipole precursor.
