Regio- and enantioselective cobalt-catalyzed reductive [3+2] cycloaddition reaction of alkynes with cyclic enones: a route to bicyclic tertiary alcohols.
نویسندگان
چکیده
Round and round: An unusual cobalt-catalyzed regio- and enantioselective reductive [3+2] cycloaddition of cyclic enones with alkynes affording bicyclic tertiary alcohols is described. A possible mechanism involving the formation of a cobaltacyclopentene intermediate is proposed.
منابع مشابه
Cobalt-catalyzed reductive coupling of activated alkenes with alkynes.
Cobalt complex/Zn systems effectively catalyze the reductive coupling of activated alkenes with alkynes in the presence of water to give substituted alkenes with very high regio- and stereoselectivity in excellent yields. While the intermolecular reaction of acrylates, acrylonitriles, and vinyl sulfones with alkynes takes place in the presence of CoI2(PPh3)2/Zn, the reaction of enones and enals...
متن کاملChiral bis(imidazolidine)pyridine-cu complex-catalyzed enantioselective [3+2]-cycloaddition of azomethine imines with propiolates.
[3+2] Cycloaddition of azomethine imines with electron-deficient terminal alkynes was smoothly catalyzed by a chiral bis(imidazolidine)pyridine-CuOAc complex to give bicyclic pyrazolo[1,2-a]pyrazolone derivatives with up to 74% ee.
متن کاملA Highly Diastereoselective and Enantioselective Phase-Transfer Catalyzed Epoxidation of β-Trifluoromethyl-β,β-disubstituted Enones with H2O2
Trifluoromethylated organic compounds, especially chiral quaternary alcohols bearing trifluoromethyl group are of important intermediates in drugs, agrochemicals and etc.An efficient epoxidation of β-CF3-β,β-disubstituted unsaturated ketones (6) has been developed with environmental benign hydrogen peroxide as the oxidant and F5-substituted chiral qua...
متن کاملRemarkable access to fluoroalkylated trisubstituted alkenes via highly stereoselective cobalt-catalyzed hydrosilylation reaction of fluoroalkylated alkynes.
Hydrosilylation reaction of various fluoroalkylated alkynes with Et(3)SiH in the presence of a catalytic amount of Co(2)(CO)(8) was investigated. The hydrosilylation of the alkynes having fluoroalkyl and aryl groups took place smoothly with good regioselectivity (ca. 80:20). In sharp contrast, the reaction of the alkynes having a fluoroalkyl group and a benzyl-type substituent, or various propa...
متن کاملRegio- and Enantioselective Cobalt-Catalyzed Sequential Hydrosilylation/Hydrogenation of Terminal Alkynes.
A highly regio- and enantioselective cobalt-catalyzed sequential hydrosilylation/hydrogenation of alkynes was developed to afford chiral silanes. This one-pot method is operationally simple and atom economic. It makes use of relatively simple and readily available starting materials, namely alkynes, silanes, and hydrogen gas, to construct more valuable chiral silanes. Primary mechanistic studie...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Angewandte Chemie
دوره 51 42 شماره
صفحات -
تاریخ انتشار 2012