Palladium-catalyzed highly regio- and stereoselective synthesis of (1E)- or (1Z)-1,2-dihalo-1,4-dienes via haloallylation of alkynyl halides.
نویسندگان
چکیده
A highly efficient and selective synthesis of (1E)- or (1Z)-1,2-dihalo-1,4-dienes via Pd-catalyzed coupling of haloalkynes and allylic halides is described. The (1E)-1,2-dihalo-1,4-dienes were generated in good yields with excellent stereoselectivities (1E/1Z up to >98/2), while (1Z)-1,2-dihalo-1,4-dienes were produced in excellent yields and stereoselectivities (1Z/1E up to >98/2) by simply adding stoichiometric lithium halides.
منابع مشابه
Palladium-catalyzed haloallylation of aromatic ynol ethers with allyl chlorides: a highly regio- and stereoselective approach to (1E)-α-chloroenol ethers.
Described herein is a Pd-catalyzed haloallylation of aromatic ynol ethers and allyl chlorides, allowing facile access to (1E)-α-chloroenol ethers in a highly regio- and stereoselective manner. The synthetic utility of this method is demonstrated well by the synthesis of the stereodefined multisubstituted enol ethers and α-allylated carbonyl compounds.
متن کاملHighly stereoselective synthesis of (Z)-1,2-dihaloalkenes by a Pd-catalyzed hydrohalogenation of alkynyl halides.
An unprecedented Pd-catalyzed hydrohalogenation of alkynyl halides for the regio- and stereoselective synthesis of (Z)-1,2-dihaloalkenes has been realized using [(allyl)PdCl](2) as the catalyst and cis,cis-1,5-cyclooctadiene as the ligand. The advantages of this protocol are well illustrated by the assembly of trisubstituted (Z)-enynes and multifunctional benzenes via iterative cross-coupling r...
متن کاملMild and selective palladium-catalyzed dimerization of terminal alkynes to form symmetrical (Z,Z)-1,4-dihalo-1,3-dienes.
A regioselective and stereoselective palladium-catalyzed dimerization of terminal alkynes method for the synthesis of symmetrical (Z,Z)-1,4-dihalo-1,3-dienes is presented. In the presence of a catalytic amount of PdX(2) and 3 equiv of CuX(2) (X = Cl and Br), terminal alkynes were dimerized to afford (Z,Z)-1,4-dihalo-1,3-dienes in good yields. The results showed that the effect of solvent had a ...
متن کامل1-(Triethoxysilyl)buta-1,3-dienes—New Building Blocks for Stereoselective Synthesis of Unsymmetrical (E,E)-1,4-Disubstituted 1,3-dienes
A convenient methodology for the highly stereoselective synthesis of unsymmetrical (1E,3E)-1,4-disubstituted 1,3-dienes based on palladium-catalyzed Hiyama cross-coupling reaction of 1-(triethoxysilyl)-substituted buta-1,3-dienes with aryl iodides is reported.
متن کاملHighly regio- and stereoselective intermolecular tandem reaction to synthesize chloro-substituted 1,3-butadienes.
A palladium catalyzed highly regio- and stereoselective intermolecular tandem reaction of alkynes, CuCl(2) and alkenes by a sequence of chloropalladation/Heck reaction to produce chloro-substituted 1,3-dienes is achieved.
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:
- Chemical communications
دوره 47 7 شماره
صفحات -
تاریخ انتشار 2011