Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents

• Jiangfei Chen,
• Yi-Lin Qu,
• Ming Yuan,
• Xiang-Mei Wu,
• Heng-Pei Jiang,
• Ying Fu and
• Shengrong Guo

Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98

• -/trifluoroalkylation reagents, α-carbonyl alkyl bromides/alcohols, alkyl halides, and alkyl carboxylic acids, have been successfully applied to this transformation to afford 3-substituted indolin-2-ones. In 2013, Li’s group reported a novel DTBP(di-tert-butyl peroxide)-mediated oxidative 1,2-alkylarylation of

• -methylpiperidine, proved compatible with the reaction conditions, yielding the corresponding 3-(2-oxoethyl)indolin-2-ones 5a–g in 40–78% yields. Following a detailed investigation, a plausible mechanism was proposed, as illustrated in Scheme 3. Initially, TBHP undergoes cleavage by Fe2+ to generate a tert-butoxy

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

• Renato L. Carvalho,
• Amanda S. de Miranda,
• Mateus P. Nunes,
• Roberto S. Gomes,
• Guilherme A. M. Jardim and
• Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

• high importance in the field of Alzheimer’s disease studies [169]. In 2020, Xu and co-workers described an unprecedented dual C–H functionalization of indolin-2-ones and benzofuran-2-ones via an oxidative C(sp3)–H cross-coupling protocol catalyzed by inexpensive FeCl3 and ligand-free conditions (Scheme

Multicomponent reactions (MCRs): a useful access to the synthesis of benzo-fused γ-lactams

• Edorta Martínez de Marigorta,
• Jesús M. de Los Santos,
• Ana M. Ochoa de Retana,
• Javier Vicario and
• Francisco Palacios

Beilstein J. Org. Chem. 2019, 15, 1065–1085, doi:10.3762/bjoc.15.104

• methods include the efficiency in saving raw materials and working time. However, there is still a need of new catalytic systems to allow the enantioselective preparation of these heterocycles by multicomponent reactions. Keywords: indolin-2-ones; isoindolinones; γ-lactams; multicomponent reactions; 2

• , Figure 1) are generated, while if such fusion takes place between the 4- and 5-positions of the γ-lactam ring, 2-oxindoles (also named as indolin-2-ones III, Figure 1) are formed. The isoindolinone structural motif is a part of the core of many natural products [2]. To cite some examples, cichorine [3

A new and convenient synthetic way to 2-substituted thieno[2,3-b]indoles

• Roman A. Irgashev,
• Arseny A. Karmatsky,
• Gennady L. Rusinov and
• Valery N. Charushin

Beilstein J. Org. Chem. 2015, 11, 1000–1007, doi:10.3762/bjoc.11.112

• the starting materials, followed by treatment of the intermediate 3-(2-oxo-2-(hetero)arylethylidene)indolin-2-ones with Lawesson’s reagent. The latter process involves two sequential reactions, namely reduction of the C=C ethylidene double bond of the intermediate indolin-2-ones followed by the Paal

• adducts can be dehydrated easily by acidic agents to form crotonic condensation products, namely 3-(2-oxo-2-(hetero)arylethylidene)indolin-2-ones 10, which can undergo reduction of the C=C double bond in the presence of Na2S2O4 [29], H2/Pd(C) [30], or Me3P–H2O [31] (Scheme 2) into the corresponding

• indolin-2-ones 11. Compounds 11 bearing the fragment of 4-oxobutyramides (1,4-dicarbonyl derivatives) can be cyclized into thieno[2,3-b]indoles by using the Paal–Knorr reaction with such thionation agents, as P4S10 or Lawesson’s reagent. This four-step route to thieno[2,3-b]indoles via the formation of

Direct alkenylation of indolin-2-ones by 6-aryl-4-methylthio-2H-pyran-2-one-3-carbonitriles: a novel approach

• Sandeep Kumar,
• Ramendra Pratap,
• Abhinav Kumar,
• Brijesh Kumar,
• Vishnu K. Tandon and
• Vishnu Ji Ram

Beilstein J. Org. Chem. 2013, 9, 809–817, doi:10.3762/bjoc.9.92

• , Lucknow-226001, India 10.3762/bjoc.9.92 Abstract A direct one-pot base-induced alkenylation of indolin-2-ones has been developed by using 6-aryl-4-methylthio-2H-pyran-2-one-3-carbonitriles. Different bases such as MeONa, NaH and t-BuONa have been used to optimize the reaction conditions to obtain the

• desired product. NaH in THF was found to be the most suitable for the alkenylation of indolin-2-ones. Reaction in the presence of other bases led to the formation of 1-aryl-3-methoxy/methylthio-5H-dibenzo[d,f][1,3]diazepin-6(7H)-ones. Quantum chemical calculations have been performed to explain the nature

• -pyran-2-ones have not been investigated for the alkenylation of indolin-2-ones. An extensive literature survey on the pharmacological properties of 3-alkenylindolin-2-ones revealed that they possess potent antitumor [2][3][4][5], antipyretic [6], antifungal [7][8], anti-inflammatory [9], and analgesic

A thermally-induced, tandem [3,3]-sigmatropic rearrangement/[2 + 2] cycloaddition approach to carbocyclic spirooxindoles

• Kay M. Brummond and
• Joshua M. Osbourn

Beilstein J. Org. Chem. 2010, 6, No. 33, doi:10.3762/bjoc.6.33

• product containing this basic skeleton is welwitindolinone A isonitrile (4); a compound that has recently captured the attention of the synthetic community [3][4]. Spiro[cyclobutane-1,3'-indolin]-2'-ones (3, n = 0) have previously been prepared but the synthetic approach is mostly limited to simple

• vinylidene indolin-2-ones. A tandem [3,3]-sigmatropic rearrangement/[2 + 2] cycloaddition. A thermal [2 + 2] cycloaddition reaction. A tandem [3,3]-sigmatropic rearrangement/[2 + 2] cycloaddition. Synthesis of spirooxindoles. Supporting Information General methods, experimental and spectral data are