Asymmetric Mn(III)-based radical synthesis of functionalized 2,3-dihydrofurans

Manganese(III) Acetate-mediated Oxidative Cyclization of a-Methylstyrene and trans-Stilbene with b-Ketosulfones

“…For cis -2,3-dihydrofuran, the vicinal coupling constant of the two methine protons proved to be J = 7–10 Hz, while for trans -2,3-dihydrofuran the vicinal coupling constant J = 4–7 Hz [38]. Moreover, these results agree with previous studies reporting trans -dihydrofuran diastereoselective synthesis via Mn(OAc) 3 mediated radical oxidative cyclizations starting from 1,2-disubstituted alkenes and β-ketonitriles [39,40] or β-ketoesters [41]. One of these studies [40] showed that the stereochemistry of Mn(OAc) 3 mediated oxidative cyclizations is not influenced by the stereochemistry of the starting alkene ( cis or trans -stilbene).…”

Ionic liquid attached to colloidal silica nanoparticles: as high performance catalyst for the preparation of dihydrofurans under microwave irradiation

“…These features make dihydrofurans useful targets in organic synthesis. A number of methods have been developed for the synthesis of dihydrofurans in the presence of diverse catalysts, such as manganese(III) acetate [6], potassium carbonate [7], piperidine [8], cerium(IV) ammonium nitrate (CAN) [9], copper(I) triflate [10], triphenylphosphine (Ph 3 P) [11], [BMIm]OH [12], N-methyl imidazole [13], NaOH [14], and Et 3 N [15]. Some of the reported procedures endure drawbacks such as long reaction times, and undesirable reaction conditions.…”

Regio- and diastereoselective synthesis of trans-dihydrofuran-3-carboxamides by radical addition of 1,3-dicarbonyl compounds to acrylamides using manganese(III) acetate and determination of exact configuration by X-ray crystallography

“…Manganese(III) acetate [6][7][8][9][10] and cerium(IV) ammonium nitrate (CAN) [11][12][13][14] are widely used for C-C bond formation and synthesis of polyfunctional organic compounds. It is well known that Mn(OAc)3 or CAN mediated radical reaction of 1,3-dicarbonyl compounds with alkenes produce dihydrofuran derivatives.…”

“…It is well known that Mn(OAc)3 or CAN mediated radical reaction of 1,3-dicarbonyl compounds with alkenes produce dihydrofuran derivatives. Mn(OAc)3, CAN or Ag(I)/Celite mediated radical reactions of 1,3-dicarbonyl compounds with unsymmetrically alkenes such as (1-pyridin-2-yl)-enones, 9 unsaturated ketones, 15,16 cinnamates, 7,14 and unsaturated ether, 11,17 have been reported. Our research group has focused on the radical reaction of 1,3-dicarbonyls and 3-oxopropanenitriles with unsaturated systems.…”