regio-selective hydroarylation of terminal 1,3-dienes has been developed. This chemistry afforded the terminal alkenyl group containing products, which are a kind of versatile precursor for organic synthesis, from 1,3-dienes by a practical one-step reaction. With good functional group tolerance, this protocol could be used to make a series of bio-active compounds using readily accessible starting materials.
allylation product in the presence of a catalytic amount of the (cyclooctadiene)rhodium(I) chloride dimer [Rh(cod)Cl]2}, sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (NaBARF), and triphenyl phosphite [P(OPh)3] in refluxing 1,2-dichloroethane. Primary, secondary and tertiary benzyl acetates could be used for the reaction. Moreover, allylation of gem-benzyl acetate was possible with [Rh(cod)Cl]2, NaBARF
Enantioselective Allylic Alkylation with 4-Alkyl-1,4-dihydro-pyridines Enabled by Photoredox/Palladium Cocatalysis
作者:Hong-Hao Zhang、Jia-Jia Zhao、Shouyun Yu
DOI:10.1021/jacs.8b10766
日期:2018.12.12
alkylation has been achieved enabled by the merger of photoredox and palladiumcatalysis. In this dual catalytic process, alkyl radicals generated from 4-alkyl-1,4-dihydropyridines act as the coupling partners of the π-allyl palladium complexes. The generality of this method has been illustrated through the reaction of a variety of allylesters with 4-alkyl-1,4-dihydropyridines. This mechanistically novel
Palladium-catalyzed cross-coupling reaction of bis(iodozincio)methane with iodoarenes carrying various functionalities such as ester, boryl, cyano, and halo groups proceeded chemoselectively to give the corresponding arenylmethylzinc species efficiently. The moderate reactivity of the gem-dizinc reagent imparted functional group tolerance to the process. The transformations from iodoheteroarenes were also performed; in the case of iodopyridine derivatives, the nickel-catalyzed reaction gave the corresponding organozinc species efficiently. The obtained arenylmethylzinc species underwent the copper-mediated coupling reaction with a range of organic halides.