Enantioselective N-heterocyclic carbene-catalyzed nucleophilic dearomatization of alkyl pyridiniums.
نویسندگان
چکیده
NHC-catalyzed nucleophilic dearomatization of alkyl pyridiniums has been achieved to generate 1,4-dihydropyridines with high enantioselectivity. This is a rare example of catalytic, asymmetric addition of a nucleophile to the activated pyridinium that prefers C-4 functionalization leading to the 1,4-dihydropyridine with high selectivity.
منابع مشابه
Enantioselective N-heterocyclic carbene-catalyzed nucleophilic dearomatization of alkyl pyridiniums† †Electronic supplementary information (ESI) available: Experimental conditions and compound characterization. CCDC 1555492. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7sc02648j Click here for additional data file. Click here for additional data file.
All reactions were carried out with magnetic stirring under an atmosphere of argon in oven-dried glassware. Methanol was purchased from Sigma-Aldrich and stored in an anhydrous atmosphere. Sodium acetate was purchased from Aldrich and stored under anhydrous atmosphere. H NMR spectra were recorded on Varian 400 MHz spectrometer at ambient temperature or a Bruker Avance III 500 (500 MHz). Data is...
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ورودعنوان ژورنال:
- Chemical science
دوره 8 9 شماره
صفحات -
تاریخ انتشار 2017