Diastereoselective Access to Enantiomerically Pure cis-2,3-Disubstituted Pyrrolidines
作者:Pierre-Olivier Delaye、Tarun K. Pradhan、Émilie Lambert、Jean-Luc Vasse、Jan Szymoniak
DOI:10.1002/ejoc.201000255
日期:——
3-disubstituted pyrrolidines is reported that involves diastereoselective allylation of (R)-phenylglycinol-derived imines and a sequential hydrozirconation-cyclization. A number of pyrrolidine derivatives bearing aryl, heteroaryl, alkyl and alkenyl groups have been prepared in this way. Such compounds are useful buildingblocks in the synthesis of molecules of biological interest, as illustrated by
the Zr–Zn transmetallation step, which appears to be beneficial for the stereoselectivity of the reaction. In the specific case of coupling of imines with racemic chiral allylzinc compounds, this method provides highlydiastereoselective access to valuable enantiomerically enriched amines with high synthetic potential.
Cyclopent-2-enylaluminium as allylzinc precursor for the diastereoselective allylmetallation of non-racemic imines: applications to the synthesis of enantiomerically enriched heterocycles
A sequential titanium-catalyzed/hydroalumination/transmetallation/allylation of non-racemic imines which provides tunable homoallylamines for heterocyclic synthesis is presented.
一种顺序进行的钛催化/氢化铝/金属转移/烯丙基化反应,用于合成杂环化合物中可调节的同烯丙基胺。
Homoallylic amines as efficient chiral inducing frameworks in the conjugate addition of amides to α,β-unsaturated esters. An entry to enantio-enriched diversely substituted amines
The diastereoselective conjugateaddition of secondary homoallylamines, obtained in the enantioenriched form via allylmetallation of imines, to α,β-unsaturated esters is reported. This method allows access to valuable building blocks as well as heterocyclic skeletons, providing tertiary amines bearing two chains integrating a stereogenic center adjacent to the nitrogen atom.