Oxindole synthesis by palladium-catalysed aromatic C–H alkenylation
作者:Satoshi Ueda、Takahiro Okada、Hideko Nagasawa
DOI:10.1039/b926560k
日期:——
A strategy involving palladium-catalysed aromatic C-H functionalisation/intramolecular alkenylation provides a convenient and direct synthesis of 3-alkylideneoxindoles. In the presence of 5 mol% of PdCl(2)MeCN(2) and AgOCOCF(3), a wide variety of N-cinnamoylanilines gave 3-alkylideneoxindoles in moderate to good yield.
Bromo Radical‐Mediated Photoredox Aldehyde Decarbonylation towards Transition‐Metal‐Free Hydroalkylation of Acrylamides at Room Temperature
作者:Zhaozhao Sun、Huawen Huang、Qiaolin Wang、Guo‐Jun Deng
DOI:10.1002/adsc.202101188
日期:2022.1.18
Herein, we report a visible-light-mediated hydroalkylation reaction of alkenes using easily available aldehydes as alkyl sources via bromo radical-promoted photoredox decarbonylation. This protocol provides an alternative entry to C(sp3)−C(sp3) bond formation and features considerable advantages including mild and clean reaction conditions, obviation for transition-metal catalyst, and good functional
All-Carbon-Substituted Quaternary Carbon Atoms in Oxindoles by an Aerobic Palladium(II)-Catalyzed Ring Closure onto Tri- and Tetrasubstituted Double Bonds
作者:Julia A. Schiffner、Martin Oestreich
DOI:10.1002/ejoc.201001526
日期:2011.2
Oxidative palladium(II)-catalyzed cyclization of α,β-unsaturated amides derived from electron-rich anilines is reported. The aerobic ring closure of tri- and tetrasubstituted alkenes yields oxindoles with congested all-carbon-substituted quaternary carbon atoms. The ring-size selectivity is excellent. Selected unsymmetrically substituted arenes cyclize with perfect regioselectivity. Experimental evidence
据报道,氧化钯 (II) 催化的 α,β-不饱和酰胺环化源自富电子苯胺。三取代和四取代烯烃的有氧闭环产生具有拥挤的全碳取代季碳原子的羟吲哚。环尺寸选择性非常好。选定的不对称取代芳烃以完美的区域选择性环化。实验证据表明,该机制可能涉及 Friedel-Crafts 型亲电取代而不是直接的 C-H 键活化。
Oxidative kupplung von 1,2-dienen mit isocyanaten am lig-nickel(0)-system
作者:Heinz Hoberg、Klaus Sümmermann
DOI:10.1016/0022-328x(84)85058-5
日期:1984.10
Isocyanates undergo a 1/1 oxidative coupling reaction with 1,2-dienes and Lig-Ni0 systems to give azanickelacyclopentanones. The coupling to form the nickela complexes proceeds in such a way that the exo-methylene group is conjugated with the carbonyl group. The influence of the ligands and the temperature on the regioselectivity of the CC coupling is reported.
Catalyticasymmetricepoxidation of α-methyl α,β-unsaturated carboxylic acid derivatives was achieved using anilide as a template. The Pr(Oi-Pr)3-6,6′-Ph-BINOL complex (10 mol%) with a Ph3P(O) (30 mol%) additive promoted the epoxidation of anilides in up to 99% yield and 88% ee. For α-methyl-β-Ph α,β-unsaturated anilide, the Gd(Oi-Pr)3-6,6′-I-BINOL complex (10 mol%) with Ar3P(O) (30 mol%, Ar = 4-methoxyphenyl)