Enantio- and Diastereoselective 1,2-Additions to α-Ketoesters with Diborylmethane and Substituted 1,1-Diborylalkanes
نویسندگان
چکیده
منابع مشابه
Enantio and diastereoselective addition of phenylacetylene to racemic α-chloroketones.
In this report, we have presented the first diastereoselective addition of phenylacetylene to chiral racemic chloroketones. The addition is controlled by the reactivity of the chloroketones that allowed the stereoselective reaction to be performed at -20 °C. Chiral racemic chloroketones are used in the reaction. By carefully controlling the temperature and the reaction time we were able to isol...
متن کاملa comparison of teachers and supervisors, with respect to teacher efficacy and reflection
supervisors play an undeniable role in training teachers, before starting their professional experience by preparing them, at the initial years of their teaching by checking their work within the proper framework, and later on during their teaching by assessing their progress. but surprisingly, exploring their attributes, professional demands, and qualifications has remained a neglected theme i...
15 صفحه اولSquaramide-catalysed enantio- and diastereoselective sulfa-Michael addition of thioacetic acid to α,β-disubstituted nitroalkenes.
A highly enantio- and diastereoselective sulfa-Michael addition of thioacetic acid to α,β-disubstituted nitroalkenes catalysed by a chiral squaramide organocatalyst has been described. This organocatalytic reaction at an extremely low catalyst loading (0.2 mol%) furnished synthetically useful β-nitro sulfides in excellent yields with good diastereoselectivities and high enantioselectivities (up...
متن کاملThiourea-catalyzed highly enantio- and diastereoselective additions of oxindoles to nitroolefins: application to the formal synthesis of (+)-physostigmine.
Oxindoles and their indoline derivatives are common structural motifs found in a wide array of natural and biologically active molecules. Most catalytic methods for the asymmetric syntheses of these compounds rely heavily on the use of transition-metal catalysts. In contrast, alternative catalytic procedures involving organocatalysis are scarce. Herein we disclose a conceptually novel organocat...
متن کاملOrganocatalytic enantio- and diastereoselective synthesis of highly substituted δ-lactones via a Michael-cyclization cascade.
An organocatalyzed Michael-cyclization cascade approach of readily available α,β-unsaturated aldehydes and pyrazoleamides has been developed to get highly substituted δ-lactones in excellent enantioselectivities (up to 97%) and diastereoselectivities. The δ-lactones so obtained could easily be transformed into benzazepine derivatives with excellent enantio- and diastereoselectivities. Furthermo...
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: 2016
ISSN: 1433-7851
DOI: 10.1002/anie.201603465