Manganese(III) Acetate Mediated Free Radical Cyclization of 1,3-Dicarbonyl Compounds with Sterically Hindered Olefins

Authors : Mehmet YILMAZ, Emre BİÇER and A Tarık PEKEL

Pages : 579-587

View : 18 | Download : 9

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The manganeseinsert ignore into journalissuearticles values(III); acetate mediated radical cyclization of dimedone 1a, 2,4-pentanedione 1b, ethyl acetoacetate 1c, 1,3-cyclohexanedione 1d and 5-phenyl-1,3-cyclohexanedione 1e with 1,1-diphenyl-1-butene 2a afforded 4,5-dihydrofurans insert ignore into journalissuearticles values(3c, 3e); and tetrahydrobenzofurans insert ignore into journalissuearticles values(3a, 3g, 3h); in good yields insert ignore into journalissuearticles values(55% - 77%);. Additionally, the reactions of trifluoromethyl-group containing 1,3-dicarbonyls, 4,4,4-trifluoro-1-phenylbutane-1,3-dione 1f and 4,4,4-trifluoro-1-thien-2ylbutane-1,3-dione 1g with 2a 3-trifluoroacetyl-4,5-dihydrofurans gave in 74% and 78% yields, respectively. Treatment of 1a, 1b and 1c with 1,2-diphenyl-1-pentene 2a resulted in the formation of tetrahydrobenzofuran 3b and 4,5-dihydrofurans 3d and 3f in lower yields.
Keywords : Manganese III, acetate, free radical cyclization, 1, 3 dicarbonyl, 4, 5 dihydrofuran, tetrahydrobenzofuran, trifluoroacetyl, oxidative addition