Transition-metal-free Chemoselective Oxidative C−C Coupling of the sp<sup>3</sup>C−H Bond of Oxindoles with Arenes and Addition to Alkene: Synthesis of 3-Aryl Oxindoles, and Benzofuro- and Indoloindoles
A transition‐metal (TM)‐free and halogen‐free NaOtBu‐mediated oxidative cross‐coupling between the sp3 C−H bond of oxindoles and sp2 C−H bond of nitroarenes has been developed to access 3‐aryl substituted and 3,3‐aryldisubstituted oxindoles in DMSO at room temperature in a short time. Interestingly, the sp3 C−H bond of oxindoles could also react with styrene under TM‐free conditions for the practical
Iron‐Catalyzed Cross‐Dehydrogenative Coupling of Oxindoles with Thiols/Selenols for Direct C(
<i>sp</i>
<sup>
<i>3</i>
</sup>
)−S/Se Bond Formation
作者:Lu‐Shan Huang、Dong‐Yang Han、Da‐Zhen Xu
DOI:10.1002/adsc.201900400
日期:2019.9.3
The C−X (S/Se) bonds are common and ubiquitous in natural products and pharmaceuticals. Here, we report an iron‐catalyzedcross‐dehydrogenativecoupling (CDC) reaction for the direct synthesis of C(sp3)−X (S/Se) bonds from oxindoles, phenylacetamides, pyrazolones, phenylacetonitriles and ethyl cyanoacetate with thiols and selenols. All the reactions were performed under simple and mild conditions,
Iron‐Catalyzed Borrowing Hydrogen
<i>C</i>
‐Alkylation of Oxindoles with Alcohols
作者:Mubarak B. Dambatta、Kurt Polidano、Alexander D. Northey、Jonathan M. J. Williams、Louis C. Morrill
DOI:10.1002/cssc.201900799
日期:——
general and efficient iron‐catalyzed C‐alkylation of oxindoles has been developed. This borrowing hydrogen approach employing a (cyclopentadienone)iron carbonyl complex (2 mol %) exhibited a broad reaction scope, allowing benzylic and simple primary and secondary aliphatic alcohols to be employed as alkylating agents. A variety of oxindoles underwent selective mono‐C3‐alkylation in good‐to‐excellent
artificial catalysts for asymmetric synthesis. Polyfunctional catalysts are considered to be a promising tool for achieving excellent catalytic efficiency. A polyfunctional catalyst system was developed, which incorporates two Lewisacidic/Brønsted basic cobalt centers in combination with triazolium moieties that are crucial for high reactivity and excellent stereoselectivity in the direct1,4‐addition of
Organocatalytic Enantioselective Stereoablative Hydroxylation of 3-Halooxindoles: An Effective Method for the Construction of Enantioenriched 3-Substituted 3-Hydroxy-2-Oxindoles
3‐Substitutedoxindoles as electrophilic partners: An unprecedented method for the construction of hydroxylated 3‐substitutedoxindoles in high yields and excellent enantioselectivities through stereoablative hydroxylation of 3‐halooxindoles with an organocatalyst has been developed. This process not only differs from the common convention of using 3‐substitutedoxindoles as nucleophiles, but also