Iridium-Catalyzed Cyclization of Isoxazolines and Alkenes: Divergent Access to Pyrrolidines, Pyrroles, and Carbazoles
作者:Zu-Feng Xiao、Ting-Hui Ding、Sheng-Wei Mao、Zaher Shah、Xiao-Shan Ning、Yan-Biao Kang
DOI:10.1021/acs.orglett.6b02905
日期:2016.11.4
iridium-complex-catalyzed N–O-cleaving rearrangement/cyclization of 2,3-dihydroisoxazoles with alkenes has been developed. It provides divergent access to multiple substituted pyrrolidines, pyrroles, and carbazoles. The iridium catalyst remains highlycatalytic active after seven cycles. The gram-scale synthesis afforded a carbazole with strong bluish-violet fluorescence.
Unexpected cyclization of <i>ortho</i>-nitrochalcones into 2-alkylideneindolin-3-ones
作者:Nicolai A. Aksenov、Dmitrii A. Aksenov、Nikolai A. Arutiunov、Daria S. Aksenova、Alexander V. Aksenov、Michael Rubin
DOI:10.1039/d0ra03520c
日期:——
An original, facile, and highly efficient method for the preparation of 2-(3-oxoindolin-2-ylidene)acetonitriles from ortho-nitrochalcones is described. The featured transformation is a triggered Michael addition of the cyanide anion to the chalcone followed by a cascade cyclization mechanistically related to the Baeyer–Drewson reaction.
Synthesis of 2-carboxyaniline-substituted maleimides from 2′-nitrochalcones
作者:Nicolai A. Aksenov、Dmitrii A. Aksenov、Daniil D. Ganusenko、Igor A. Kurenkov、Alexander V. Leontiev、Alexander V. Aksenov
DOI:10.1039/d3ob00197k
日期:——
A practical, one-pot approach to 3-anilino-4-(het)arylmaleimides by simple heating of aqueous DMSO solution of 2′-nitrochalcones with potassiumcyanide in the presence of formic acid has been developed. This new reaction provides effective access to a variety of β-substituted α-aminomaleimides which have recently become a subject of growing interest as small, easily modified and environmentally responsive