Diastereo- and Enantioselective Synthesis of Fluorine Motifs with Two Contiguous Stereogenic Centers
作者:Sudipta Ponra、Wangchuk Rabten、Jianping Yang、Haibo Wu、Sutthichat Kerdphon、Pher G. Andersson
DOI:10.1021/jacs.8b08778
日期:2018.10.24
motifs, in particular, chiral fluorine molecules with two contiguous stereogeniccenters, has attracted much interest in research due to the limited number of methods available for their preparation. Herein, we report an atom-economical and highlystereoselective synthesis of chiral fluorine molecules with two contiguous stereogeniccenters via azabicyclo iridium-oxazoline-phosphine-catalyzed hydrogenation
Diethylzinc-Mediated One-Step Stereoselective Synthesis of α-Fluoroacrylates from Aldehydes and Ketones. Two Different Pathways Depending on the Carbonyl Partner
A efficient methodology allowing the one-pot stereoselective synthesis of alpha-fluoroacrylates, based on the addition of ethyl dibromofluoroacetate to a carbonyl derivative using diethylzinc as organometallic mediator, is described. Two different pathways have been identified depending on the involved carbonyl partner. In the case of aldehydes, an E2-type mechanism has been identified, whereas ketones go through an E1cb-type mechanism.
Extending the Substrate Scope in the Hydrogenation of Unfunctionalized Tetrasubstituted Olefins with Ir-P Stereogenic Aminophosphine–Oxazoline Catalysts
作者:Maria Biosca、Ernest Salomó、Pol de la Cruz-Sánchez、Antoni Riera、Xavier Verdaguer、Oscar Pàmies、Montserrat Diéguez
DOI:10.1021/acs.orglett.8b04084
日期:2019.2.1
MaxPHOX-type ligands have been successfully applied in the challenging asymmetrichydrogenation of tetrasubstitutedolefins under mild reaction conditions. Gratifyingly, these catalyst precursors are able to efficiently hydrogenate not only a range of indene derivatives (ee’s up to 96%) but also 1,2-dihydronapthalene derivatives and acyclic olefins (ee’s up to 99%), which both constitute the most challenging