Copper(II)-Promoted Cyclization/Difunctionalization of Allenols and Allenylsulfonamides: Synthesis of Heterocycle-Functionalized Vinyl Carboxylate Esters
摘要:
A unique method to affect intramolecular aminooxygenation and dioxygenation of allenols and allenylsulfonamides is described. These operationally simple reactions occur under neutral or basic conditions where copper(II) carboxylates serve as reaction promoter, oxidant, and carboxylate source. Moderate to high yields of heterocycle-functionalized vinyl carboxylate esters are formed with moderate to high levels of diastereoselectivity. Such vinyl carboxylate esters could serve as precursors to alpha-amino and alpha-oxy ketones and derivatives thereof.
Copper(II)-Promoted Cyclization/Difunctionalization of Allenols and Allenylsulfonamides: Synthesis of Heterocycle-Functionalized Vinyl Carboxylate Esters
摘要:
A unique method to affect intramolecular aminooxygenation and dioxygenation of allenols and allenylsulfonamides is described. These operationally simple reactions occur under neutral or basic conditions where copper(II) carboxylates serve as reaction promoter, oxidant, and carboxylate source. Moderate to high yields of heterocycle-functionalized vinyl carboxylate esters are formed with moderate to high levels of diastereoselectivity. Such vinyl carboxylate esters could serve as precursors to alpha-amino and alpha-oxy ketones and derivatives thereof.
Palladium-Catalyzed Arylation of α-Methylene-γ-butyrolactone: 3-Benzylfuran-2(5<i>H</i>)-ones vs (<i>Z</i>)-Benzylidene-γ-butyrolactones and Their Reduction to 3-Benzyl-γ-butyrolactones
[GRAPHICS]The palladium-catalyzed arylation of the alpha-methylene-gamma-butyrolactone proceeds in good yields and may be directed toward the synthesis of 3-benzylfuran-2(5H)-ones when the starting aryl iodides contain strongly electron withdrawing groups. The combined palladium-catalyzed arylation/hydrogenation of the alpha-methylene-gamma-butyrolactone represents a new simple entry into functionalized alpha-benzyl-gamma-butyrolactones.
Palladium-Catalysed Vinylic Substitution of Aryl/Vinyl Iodides and Triflates with α-Methylene-γ-butyrolactone − An Application to the Synthesis of 3-Alkyl-γ-Butyrolactones through Combined Palladium-Catalysed Coupling/Hydrogenation Reactions
Copper(II)-Promoted Cyclization/Difunctionalization of Allenols and Allenylsulfonamides: Synthesis of Heterocycle-Functionalized Vinyl Carboxylate Esters
作者:Barbara J. Casavant、Zainab M. Khoder、Ilyas A. Berhane、Sherry R. Chemler
DOI:10.1021/acs.orglett.5b02833
日期:2015.12.18
A unique method to affect intramolecular aminooxygenation and dioxygenation of allenols and allenylsulfonamides is described. These operationally simple reactions occur under neutral or basic conditions where copper(II) carboxylates serve as reaction promoter, oxidant, and carboxylate source. Moderate to high yields of heterocycle-functionalized vinyl carboxylate esters are formed with moderate to high levels of diastereoselectivity. Such vinyl carboxylate esters could serve as precursors to alpha-amino and alpha-oxy ketones and derivatives thereof.