A cascade reaction of N'-(2-alkynylbenzylidene)hydrazide with allenoate in the presence of dioxygen co-catalyzed by silver triflate and copper(II) acetate under mild conditions is described, which provides an efficient approach to 2-carbonyl H-pyrazolo[5,1-a]isoquinolines.
Palladium-Catalyzed C–S Bond Cleavage with Allenoates: Synthesis of Tetrasubstituted 2-Alkenylfuran Derivatives
作者:Quannan Wang、Zhuqing Liu、Jiang Lou、Zhengkun Yu
DOI:10.1021/acs.orglett.8b02253
日期:2018.10.5
Palladium-catalyzed C–S cleavage of tetrasubstituted internal alkene α-oxo ketene dithioacetals was realized with allenoates as the coupling partners, efficiently affording tetrasubstituted 2-alkenylfuran derivatives with excellent regioselectivity under mild conditions. Allenoates acted as C1 synthons in the desulfurative [4 + 1] annulation.
Cationic Palladium-Catalyzed [5 + 2] Annulation of 2-Acylmethoxyarylboronic Acids and Allenoates: Synthesis of 1-Benzoxepine Derivatives
作者:Xufen Yu、Xiyan Lu
DOI:10.1021/jo200672w
日期:2011.8.5
The 1-benzoxepine derivatives were synthesized conveniently by cationicpalladium-catalyzed [5 + 2] annulation reaction of 2-acylmethoxyarylboronic acids with allenoates in high yields. This annulation involves the intramolecular nucleophilic addition to ketones without the formation of π-allylpalladium species.
A convenient [3 + 2] annulation of azomethine ylides with allenoates promoted by triethylamine produced highly functionalized 2,5-dihydropyrrole derivatives in moderate to excellent yields under mild conditions. The potential utility of this reaction indicates that this reaction could be performed on the gram scale and the synthesized functionalized 2,5-dihydropyrrole derivatives could be further transformed
Facile Synthesis of Azetidine Nitrones and Diastereoselective Conversion into Densely Substituted Azetidines
作者:Tyler W. Reidl、Jongwoo Son、Donald J. Wink、Laura L. Anderson
DOI:10.1002/anie.201705681
日期:2017.9.11
An electrocyclization route to azetidine nitrones from N‐alkenylnitrones was discovered that provides facile access to these unsaturated strained heterocycles. Reactivity studies showed that these compounds undergo a variety of reduction, cycloaddition, and nucleophilic addition reactions to form highly substituted azetidines with excellent diastereoselectivity. Taken together, these transformations