16616-46-9Relevant articles and documents
Optimized synthesis of 7-azaindazole by a diels-alder cascade and associated process safety
Bailly, Corinne,Bizet, Vincent,Blanchard, Nicolas,Brach, Nicolas,Gallou, Fabrice,Hoehn, Pascale,Lanz, Marian,Le Fouler, Vincent,Parmentier, Michael
, p. 776 - 786 (2020)
Although pyrimidines are not among the most reactive partners in intramolecular inverse-electron-demand [4πs + 2πs] reactions with alkynes, they can be activated under mild and practical conditions, leading to fused nitrogen-containing heterocycles. We report an optimized synthesis of a 5-iodo-7-azaindazole by a one-pot Diels-Alder cascade that starts from a pyrimidine substituted at the 2-position by an (alkynyl)hydrazone. The safety of the process and the environmental impact were thoroughly evaluated. Eventually, a selection of cross-coupling reactions of 17 were studied and found to allow the introduction of carbon- and nitrogen-based nucleophiles at the 5-position in good to excellent yields.
Indium-mediated formation of propargyl ketones from aldehydes or acyl chlorides
Augé, Jacques,Lubin-Germain, Nadège,Seghrouchni, Latifa
, p. 819 - 821 (2003)
Propargyl ketones were prepared from aldehydes via an indium-mediated alkynylation reaction followed by an indium-mediated Oppenauer oxidation. They were also obtained via an indium-mediated alkynylation of the relevant acyl chlorides.
Ynonylation of Acyl Radicals by Electroinduced Homolysis of 4-Acyl-1,4-dihydropyridines
Luo, Xiaosheng,Wang, Ping
, p. 4960 - 4965 (2021/07/20)
Herein we report the conversion of 4-Acyl-1,4-dihydropyridines (DHPs) into ynones under electrochemical conditions. The reaction proceeds via the homolysis of acyl-DHP under electron activation. The resulting acyl radicals react with hypervalent iodine(III) reagents to form the target ynones or ynamides in acceptable yields. This mild reaction condition allows wider functionality tolerance that includes halides, carboxylates, or alkenes. The synthetic utility of this methodology is further demonstrated by the late-stage modification of complex molecules.
Synthesis of 2-isoxazolyl-2,3-dihydrobenzofuransviapalladium-catalyzed cascade cyclization of alkenyl ethers
Zhou, Fei,Li, Can,Li, Meng,Jin, Yangbin,Jiang, Huanfeng,Zhang, Yingjun,Wu, Wanqing
supporting information, p. 4799 - 4802 (2021/05/25)
A novel palladium-catalyzed cascade cyclization reaction of alkenyl ethers with alkynyl oxime ethers for the construction of poly-heterocyclic scaffolds has been developed, in which the electron-rich alkene moiety functions as a three-atom unit, simultaneously dealing well with the coordination and regioselectivity of electron-rich olefins under metal catalysis. The strategy features excellent regio- and chemoselectivities as well as good functional group tolerance. Moreover, the newly formed 2-isoxazolyl-2,3-dihydrobenzofuran products can be further transformed to diverse complex heterocycles, demonstrating their potential applications in organic synthesis and medicinal chemistry.
Methylation Alkynylation of Terminal Alkenes via 1,2-Alkynyl Migration Using Dicumyl Peroxide as the Methyl Source
Qin, Yi-Qun,Chen, De,Liu, Liang,Zhang, Jia-Jia,Peng, Xin-Ju,Luo, Yong-Yue,Deng, Wei,Xiang, Jiannan
, p. 4700 - 4708 (2021/08/31)
The metal-free oxidative alkene methylation/alkynylation of 1,4-enyn-3-ols with an organic peroxide as the methyl source has been developed, which provides straightforward and practical access to the challenging quaternary-carbon-containing but-3-yn-1-one
