A bicyclic guanidine-catalyzed Michael addition of 3-benzyl substituted oxindoles to N-maleimides has been developed to produce oxindole derivatives with a quaternary carbon chiral center at the 3-position in excellent yields and enantio- and diastereoselectivities. This is the first incorporation of N-benzylic α-branched succinimides into 3,3-disubstituted oxindoles.

A novel metal-free photoredox-catalyzed cyclization reaction of N-aryl acrylamide is herein reported that provides synthetically valuable oxindole derivatives through the bis-mediation H2O and aldehyde. In this work, sustainable visible light was used as energy source, organic light-emitting molecule 4CzIPN served efficient photocatalyst. The main characteristics are environmentally friendly hi...

The title penta-cyclic oxindole alkadoid, isolated from Uncaria longiflora, crystallizes as a methanol solvate, C(20)H(22)N(2)O(4)·CH(4)O. The five-membered ring comprising the indole fused ring is nearly planar [maximum atomic deviation = 0.031 (2) Å], whereas the five-membered ring having alphatic C atoms adopts an envelope shape (with the tertiary N atom representing the flap). The six-membe...

Carbon-centered carboranyl radicals are an underdeveloped compound class. In their Research Article (e202305088), Zhi-Xiang Wang, Xiang-Yu Chen and co-workers show that the combination of carborane phosphonium salts KOAc forms a photoactive charge transfer complex for generation carbon-centered radicals, allowing access to various carborane-oxindole-pharmaceuticals.

The Suzuki-Miyaura cross-coupling of unprotected, nitrogen-rich heterocycles using precatalysts P1 or P2 is reported. The procedure allows for the reaction of variously substituted indazole, benzimidazole, pyrazole, indole, oxindole, and azaindole halides under mild conditions in good to excellent yields. Additionally, the mechanism behind the inhibitory effect of unprotected azoles on Pd-catal...

The first iron(III)/N,N'-dioxide-catalyzed asymmetric haloamination of 3-alkylidene- and 3-arylidene-indolin-2-ones was developed, affording the corresponding chiral oxindole derivatives bearing vicinal haloamine substituents with excellent results (up to 99% yield, 99% ee, >19 : 1 dr). This iron catalyst also exhibits perfect enantioselectivity for chalcone derivatives. The cooperative activat...

On direct comparison by TLC and IR we established that the alkaloids A-5 and A-4, first isolated from Vinca herbacea W. K . 1 are identical to the oxindole alkaloid majdine (I), later isolated from Vinca major L. 2' 3 and with its isomer isomajdine (II), prepared by heating of (I) in acetic anhydride 2. Based upon some spectroscopic evidence it was claimed2, that majdine was a diastereomer of c...

Ammonium monovanadate (NH4VO3) has been devoted as an efficient, commercially available, eco-friendly and reusable catalyst for the synthesis of bis(indolyl)methanes (BIMs), oxindole derivatives and also Michael adducts of indoles at 50 °C under solvent-free conditions. The reusability of this solid acid catalyst in addition with its selectivity has also been examined.

Egg shell has been utilized as a natural, green, reusable and eco-friendly reagent for the synthesis of spiro[4H-pyran-oxindole] derivatives by one-pot multicomponent reaction of isatins, 1,3-diketones, and malononitrile/ ethyl cyanoacetate. Good functional group tolerance and broad scope of usable substrates are other prominent features of the present methodology.