Fluorenes and styrenes by Au(I)-catalyzed annulation of enynes and alkynes.
نویسندگان
چکیده
Intermolecular annulation of enynes and propargyl esters to selectively produce styrenes or fluorenes is reported. The divergent arene syntheses involve a Au-catalyzed, two-pot, multistep process proceeding by cis-diastereoselective cyclopropanation, cycloisomerization, and, finally, annulation or elimination.
منابع مشابه
Au(I)-catalyzed intramolecular oxidative cyclopropanation of 1,6-enynes derived from propiolamides with diphenyl sulfoxide.
We have developed gold(I)-catalyzed oxidative cyclopropanation of 1,6-enynes derived from propiolamides employing diphenyl sulfoxide as an oxidant. 1,6-Enynes having a terminal alkyne and a propiolamide tether efficiently transformed into cyclopropane carboxaldehyde derivatives.
متن کاملGold-catalyzed efficient synthesis of 2,4-disubstituted furans from aryloxy-enynes.
A series of (E)-1-aryloxy-1-en-3-ynes has been prepared by Sonogashira coupling of 2-bromo-3-aryloxypropenoates with terminal alkynes using Pd(PPh(3))(4) and CuI as the catalysts in Et(3)N. The resulting enynyl-aryl ethers are found to be highly applicable to the synthesis of 2,4-disubstituted furans with an ester group at C-4 position through an Au/Ag-catalyzed annulation reaction under extrem...
متن کاملAu- and pt-catalyzed cycloisomerizations of 1,5-enynes to cyclohexadienes with a broad alkyne scope.
We describe the development of gold- and platinum-catalyzed cycloisomerizations of 1,5-enynes. This catalytic process displays a wide alkyne scope and furnishes a range of highly functionalized 1,4- and 1,3-cyclohexadienes. In the case of 1-siloxy-1-yne-5-enes, the reactions are efficiently catalyzed by AuCl (1 mol %) at ambient temperature to afford siloxy cyclohexadienes or the corresponding ...
متن کاملCatalytic 1,4-Rhodium(III) Migration Enables 1,3-Enynes to Function as One-Carbon Oxidative Annulation Partners in C–H Functionalizations**
1,3-Enynes containing allylic hydrogens cis to the alkyne are shown to act as one-carbon partners, rather than two-carbon partners, in various rhodium-catalyzed oxidative annulations. The mechanism of these unexpected transformations is proposed to occur through double C-H activation, involving a hitherto rare example of the 1,4-migration of a Rh(III) species. This phenomenon is general across ...
متن کاملStereoselective Ir(III)-catalyzed dimerization reaction of enynes: an entry to functionalized polyunsaturated and cyclic systems.
The Ir(III) complex [Ir(2)H(2)I(3)((rac)-Binap)(2)](+)I(-) efficiently promotes the selective dimerization of 1,6-, 1,7-enynes and functionalized alkynes. This catalytic process results in the formation of head-to-head isomers with (E)-stereoselectivity. Subsequent Rh-catalyzed cycloisomerization under reductive conditions led to the corresponding 1,2-dialkylidenecyclopentane derivatives.
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:
- Journal of the American Chemical Society
دوره 130 12 شماره
صفحات -
تاریخ انتشار 2008