The Asymmetric Aza-silyl-Prins Reaction: Synthesis of Enantiopure Piperidines
نویسندگان
چکیده
منابع مشابه
Synthesis of Enantioenriched Indolines by a Conjugate Addition/Asymmetric Protonation/Aza-Prins Cascade Reaction.
A conjugate addition/asymmetric protonation/aza-Prins cascade reaction has been developed for the enantioselective synthesis of fused polycyclic indolines. A catalyst system generated from ZrCl4 and 3,3'-dibromo-BINOL enables the synthesis of a range of polycyclic indolines in good yields and with high enantioselectivity. A key finding is the use of TMSCl and 2,6-dibromophenol as a stoichiometr...
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An approach to 2,4,5-trisubstituted piperidines is reported, in which the key step is the Prins or carbonyl ene cyclisation of aldehydes of the type 1. Prins cyclisation catalysed by concentrated hydrochloric acid in CH(2)Cl(2) at -78 degrees C afforded good yields of two of the four possible diastereomeric piperidines, with the 4,5-cis product 7 predominating in a diastereomeric ratio of up to...
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Previously, we reported an efficient asymmetric synthesis of substituted piperidines through an exocyclic chirality induced nitroalkene/amine/enone (NAE) condensation reaction. An effective protecting group strategy was developed herein to achieve enantiopure piperidines (yields up to 92%) with complete chirality retention (ee > 95%). A simple derivatization of the obtained piperidines gave thi...
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ژورنال
عنوان ژورنال: Organic Letters
سال: 2018
ISSN: 1523-7060,1523-7052
DOI: 10.1021/acs.orglett.8b03283