Enantioselective N-Heterocyclic Carbene Catalyzed Annulation Reactions with Imidazolidinones
نویسندگان
چکیده
منابع مشابه
N-Heterocyclic Carbene Catalyzed Enantioselective Annulation of Benzothiazolyl Ethyl Acetates with 2-Bromoenals.
An N-heterocyclic carbene catalyzed enantioselective [3+3] annulation of benzothiazolyl acetates with 2-bromoenals has been developed. The protocol provides a direct asymmetric synthesis of dihydro-1H-benzothiazolopyridinones in good to very good yields and medium ee values. In many cases, the virtually enantiopure heterocycles are available through a single recrystallization (99% ee).
متن کاملN-heterocyclic carbene-catalyzed highly enantioselective synthesis of substituted dihydropyranopyrazolones.
Highly optically pure multisubstituted dihydropyrano[2,3-c]pyrazol-6-(1H)-ones were synthesized via the N-heterocyclic carbene-catalyzed enantioselective [4 + 2] annulation of α-chloroaldehydes and pyrazolone-derived oxodienes.
متن کاملEnantioselective N-heterocyclic carbene-catalyzed synthesis of indenopyrones.
The chiral N-heterocyclic carbene-catalyzed [4 + 2] cyclization of α-chloroaldehydes and arylidene indanediones was developed, giving the corresponding indenopyrones in good yields with high diastereoselectivities and enantioselectivities.
متن کاملEnantioselective N-heterocyclic carbene-catalyzed nucleophilic dearomatization of alkyl pyridiniums.
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.
متن کاملN-heterocyclic carbene-catalyzed radical reactions for highly enantioselective β-hydroxylation of enals.
An N-heterocyclic carbene-catalyzed β-hydroxylation of enals is developed. The reaction goes through a pathway involving multiple radical intermediates, as supported by experimental observations. This oxidative single-electron-transfer reaction allows for highly enantioselective access to β-hydroxyl esters that are widely found in natural products and bioactive molecules.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Angewandte Chemie International Edition
سال: 2013
ISSN: 1433-7851
DOI: 10.1002/anie.201307292