Transition‐Metal‐Promoted Direct C−H Cyanoalkylation and Cyanoalkoxylation of Internal Alkenes
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Radical C−C Bond Cleavage of Cycloketone Oxime Esters
作者:Jiang Lou、Yuan He、Yunlong Li、Zhengkun Yu
DOI:10.1002/adsc.201900402
日期:2019.8.21
d alkyl‐Heck‐type cross‐coupling of olefinic C−Hbonds has been a challenge in the C−H activation area. Herein, we report FeCl3‐promoted efficient direct C−Hcyanoalkylation of internal alkenes, that is, ketene dithioacetals, with cycloketone oxime esters via radical C−C bond cleavage under the redox‐neutral conditions. With CuCl2 as the catalyst under a dioxygen atmosphere direct C−H cyanoalkoxylation
BF3·OEt2-mediated alkenylation of pyrroles with α-oxo ketene dithioacetals
作者:Xiaoge Yang、Kaikai Wu、Zhengkun Yu
DOI:10.1016/j.tetlet.2015.05.102
日期:2015.7
BF3·OEt2-mediated alkenylation of pyrroles with α-oxo ketene dithioacetals was efficiently realized, affording mono- and disubstituted ketene pyrrolyl acetals. In the cases of using N-unprotected pyrrole, the reactions gave ketene bipyrrolyl acetals as well as N,O-chelated BF2 complexes. Diverse C–S transformations were achieved for the monosubstituted products, yielding N-heterocycles or multisubstituted
A convenient base-mediated synthesis of 3-aryol-4-methyl (or benzyl)-2-methylthio furans from α-oxo ketene dithioacetals and propargyl alcohols via domino coupling/annulations
A convenient base-mediated synthesis of 3-aryol-4-methyl (or benzyl)-2-methylthio furans2has been developed through the domino coupling/annulations from α-oxo ketene dithioacetals1and propargyl alcohols.
Tetrasubstituted furans were efficiently synthesized from Fe(OAc)2-catalyzed C–H/C–H cross-dehydrogenative-coupling (CDC) reactions of activated carbonyl methylenes with S,S-functionalized internal olefins, that is, α-oxo ketene dithioacetals and analogues, under oxidative conditions. β-Ketoesters, 1,3-dicarbonyls, β-keto nitrile, and amide derivatives were used as the coupling partners. The resultant
Mediated by a catalytic amount of FeCl3, the C–H alkylation of S,S‐functionalized internal olefins, i.e., α‐oxo ketene dithioacetals and their analogues, was efficiently achieved using simple ethers and toluene derivatives as the coupling partners, di‐tert‐butyl peroxide (DTBP) as the oxidant, and DABCO⋅6 H2O as the additive. The alkylthio functionality is essential for the internal olefinic C–H bond