Cu-Catalyzed decarboxylative annulation of N-substituted glycines with 3-formylchromones: synthesis of functionalized chromeno[2,3-b]pyrrol-4(1H)-ones

Abstract

A novel protocol was developed for preparing functionalized chromeno[2,3-b]pyrrol-4(1H)-ones 3 (CMPOs) from 3-formylchromones with N-substituted glycine derivatives. The method entailed decarboxylative annulation of the acyl group of 3-formylchromones by simply...

Cu-Catalyzed Decarboxylative Annulation of N-Phenylglycines with Maleimides: Synthesis of 1H-Pyrrolo[3,4-c]quinoline-1,3(2H)-diones

“…Herein, we report a novel decarboxylative annulation of Nphenylglycine derivatives 27 with maleimides 28 to construct a series of PQLs whose skeletons comprise both quinolone and pyrrolo-1,3-dione moieties (Scheme 1). We hoped that the novel PQL target compounds would have better biological activities than quinolines and pyrrolo-1,3-diones alone.…”

“…Next, intermediate 5l was oxidized by Cu(II) to form the key carbonium ion intermediate 6l through SET and intramolecualr cyclization. Intermediate 6l underwent tautomerization to form intermediate 7l, which was converted to the target compound 3l via an oxidative aromatization reaction catalyzed by CuBr and facilitated by heat 27.…”

Cu-catalyzed decarboxylative annulation of proline derivatives: multi-component synthesis of functionalized chromeno[2,3-c]-pyrrol-9(1H)-one derivatives

“…The introduction of transition-metal catalyzed cross-coupling reactions in synthetic organic chemistry is a significant milestone. The decarboxylative cross-coupling of carboxylic acids is perhaps one of the most efficient methods used to generate C–C 3,4 and C–Z 5,6 bonds with reliability, selectivity, and predictability. 3–6 Consequently, various strategies have been developed to construct diverse compound libraries.…”

“…The decarboxylative cross-coupling of carboxylic acids is perhaps one of the most efficient methods used to generate C–C 3,4 and C–Z 5,6 bonds with reliability, selectivity, and predictability. 3–6 Consequently, various strategies have been developed to construct diverse compound libraries. However, only a few reactions based on decarboxylative cross-coupling of carboxylic acids have been used to form heterocycles via annulation.…”

Fe(OTf)3-catalyzed annulation of α,β-unsaturated ketoxime acetates with enaminones for the synthesis of functionalized 2,4-diarylpyridines

“…Enamine derivatives include enamines, enaminones/enamine esters, and 1,1-enediamines, which use various synthetic blocks to construct N-heterocycles with a broad spectrum of biological activities including anti-tumor, 22 herbicidal, pesticidal, 23 antianxiety, 24 anti-leishmanial, 25 and anti-bacterial activities. 26 Consequently, various N-heterocycles, including quinolines, pyridines, 27,28 pyrroles, 29 and indoles, 30 among others, 31 have been synthesized. To further explore the reaction of enaminones, they were reacted with α,β-unsaturated ketoxime acetates for the synthesis of N-heterocycles in the presence of different catalysts and promoters to obtain 2,4-diarylpyridines (Scheme 1).…”