Sulfhydrolysis of Acyl Ketene Dithioacetals: A Convenient Synthesis of β-Oxodithioesters
摘要:
beta-Oxodithioesters are obtained in. good yields from acyl ketenedithioacetals on treatment with hydrogen sulphide in the presence of boron trifluoride etherate in refluxing dioxane.
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
These precursors are easily accessible from aryl methyl ketones. Various functional groups like alkyl, aryl, nitrile, amine, aroyl and thiomethyl can be directly installed to the benzene ring. The one-pot approach for the construction of thiomethylated-benzene nucleus was also developed. The structure of the synthesized compound was confirmed by X-ray crystallography.
Synthesis of β-Amino-α,β-unsaturated Ketone Derivatives via Sequential Rhodium-Catalyzed Sulfur Ylide Formation/Rearrangement
作者:Jun He、Zengming Man、Yinping Shi、Chuan-Ying Li
DOI:10.1021/acs.joc.5b00521
日期:2015.5.1
a Rh(II) catalyst and β-(methylthio)-α,β-unsaturated ketones, 1-sulfonyl-1,2,3-triazoles can be converted into functionalized β-amino-α,β-unsaturated ketones via formation of α-imino rhodium carbene/sulfur ylide and subsequent rearrangement. The products decompose to useful 2-methylthiopyrrole derivatives conveniently in high yield.
Efficient trifluoromethylation of C(sp<sup>2</sup>)–H functionalized α-oxoketene dithioacetals: a route to the regioselective synthesis of functionalized trifluoromethylated pyrazoles
作者:N. Sharma、N. Kumari、T. S. Chundawat、S. Kumar、S. Bhagat
DOI:10.1039/c7ra01130j
日期:——
An operationally simple approach for the regioselective construction of diversely substituted trifluoromethylated pyrazoles via nucleophilic trifluoromethylation of iodo-substituted α-oxoketene dithioacetals is described. X-ray crystallographic studies confirmed the trifluoromethylation as well as formation of a regioselective cyclized product. Furthermore, trifluoromethylated pyrazoles bearing thiomethyl
Synthesis of a new series of pyrazolo[1,5-<i>a</i>]pyrimidines structurally related to zaleplon
作者:Pier Giovanni Baraldi、Francesca Fruttarolo、Mojgan Aghazadeh Tabrizi、Romeo Romagnoli、Delia Preti、Ennio Ongini、Hussein El-Kashef、María Dora Carrión、Pier Andrea Borea
DOI:10.1002/jhet.5570440212
日期:2007.3
The reaction between 3-(dimethylamino)/3,3-bis(methylthio)-1-(substituted)prop-2-en-1-ones and 4-substituted-5-amino-1H-pyrazoles afforded new pyrazole[1,5-a]pyrimidinesstructurallyrelated to Zaleplon. The chemical modifications introduced at the 3-, 5-, and 7-positions of the bicyclic structure revealed new promising candidates for the treatment of sleep disorders.