Consecutive four-component synthesis of trisubstituted 3-iodoindoles by an alkynylation–cyclization–iodination–alkylation sequence

• Nadia Ledermann,
• Alae-Eddine Moubsit and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2023, 19, 1379–1385, doi:10.3762/bjoc.19.99

• transition-metal catalysis [31], we disclosed an activating group-free alkynylation–cyclization sequence to (aza)indoles [32][33] that could be readily concatenated with a concluding N-alkylation of the 7-azaindole intermediate in the sense of consecutive three-component coupling–cyclization–alkylation

• (aza)indoles. As already shown for N-alkyl 7-azaindole formation in one case, the crucial 7-azaindole anion could be trapped with electrophilic iodine (from N-iodosuccinimide), resulting in a 3-iodo-7-azaindole anion, which could then be alkylated, still in a one-pot fashion [34]. Therefore, we set out

Recent developments and trends in the iron- and cobalt-catalyzed Sonogashira reactions

• Surendran Amrutha,
• Sankaran Radhika and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 262–285, doi:10.3762/bjoc.18.31

• substituents like iodo, fluoro, methyl, acetyl, and methoxy groups. The yield of the coupling product was observed to be decreased when the steric demand of aryl iodide species increased as in the case of the naphthyl-substituted iodo derivative. An efficient method for the synthesis of 7-azaindole ring

• iron complex B is formed by the oxidative addition of the iron catalyst to the pyridine derivative. Intermediate Fe species were obtained by transmetallation and finally a new carbon–carbon bond is formed by reductive elimination (Scheme 19). This method provided access to a diverse range of 7

• -azaindole derivatives under microwave irradiation that helps to reduce the reaction time and minimizes side product formation. Co-catalyzed Sonogashira cross-coupling reactions Nanoparticle-based protocols The advantages of using immobilized catalysts include the possibility of the catalyst to be easily

Catalyzed and uncatalyzed procedures for the syntheses of isomeric covalent multi-indolyl hetero non-metallides: an account

• Ranadeep Talukdar

Beilstein J. Org. Chem. 2021, 17, 2102–2122, doi:10.3762/bjoc.17.137

• the strong base led to the formation of the over-aminated product 168 (Scheme 22b) [110]. Alzheimer’s disease is caused by the β-amyloid-42 aggregation in brain tissue [111][112]. In 2017, Sreenivasachary synthesized a library of 6,5’- and 6,6’-bis(indolyl)amines and other similar 7-azaindole

Synthesis of 3-alkenylindoles through regioselective C–H alkenylation of indoles by a ruthenium nanocatalyst

• Abhijit Paul,
• Debnath Chatterjee,
• Srirupa Banerjee and
• Somnath Yadav

Beilstein J. Org. Chem. 2020, 16, 140–148, doi:10.3762/bjoc.16.16

• [30]. Das and co-workers reported the C3–H alkenylation of 7-azaindole using Pd(OAc)2 as a catalyst, Ph3P as a ligand, and Cu(OTf)2 as an oxidative cocatalyst, with molecular oxygen as the oxidant [31]. Carrow and co-workers reported mechanistic, kinetic, and selectivity studies of the C–H

Synthesis and SAR of the antistaphylococcal natural product nematophin from Xenorhabdus nematophila

• Frank Wesche,
• Hélène Adihou,
• Thomas A. Wichelhaus and
• Helge B. Bode

Beilstein J. Org. Chem. 2019, 15, 535–541, doi:10.3762/bjoc.15.47

• initiated. The syntheses of the appropriate azatryptamine derivatives (17, 18, 25, and 26) were achieved from the non-expensive and commercially available 4- and 7-azaindole (13 and 20), respectively. First, 13 and 20 were converted in a Friedel–Crafts acylation with chloroacetyl chloride (ClCH2COCl) and

Exploration of C–H and N–H-bond functionalization towards 1-(1,2-diarylindol-3-yl)tetrahydroisoquinolines

• Michael Ghobrial,
• Marko D. Mihovilovic and
• Michael Schnürch

Beilstein J. Org. Chem. 2014, 10, 2186–2199, doi:10.3762/bjoc.10.226

• poorer 5-nitroindole (5n) the yield dropped to 45% and required an increased reaction time of 3 days (Table 6, entry 14). On the other hand a good yield of 82% of 8j was obtained in the reaction with electron-rich 5-methoxyindole (5j, Table 6, entry 10). 1-Phenyl-7-azaindole was not applicable as

Palladium-catalyzed C–N and C–O bond formation of N-substituted 4-bromo-7-azaindoles with amides, amines, amino acid esters and phenols

• Rajendra Surasani,
• Dipak Kalita,
• A. V. Dhanunjaya Rao and
• K. B. Chandrasekhar

Beilstein J. Org. Chem. 2012, 8, 2004–2018, doi:10.3762/bjoc.8.227

• .8.227 Abstract Simple and efficient procedures for palladium-catalyzed cross-coupling reactions of N-substituted 4-bromo-7-azaindole (1H-pyrrole[2,3-b]pyridine), with amides, amines, amino acid esters and phenols through C–N and C–O bond formation have been developed. The C–N cross-coupling reaction of

• report on coupling of amides, amino acid esters and phenols with N-protected 4-bromo-7-azaindole derivatives. Keywords: 7-azaindole; C–N bond; C–O bond; ligand; palladium catalyst; Introduction Palladium-catalyzed C–N and C–O bond-forming reactions between 4-substituted 7-azaindoles and amides, amines

• various therapeutic areas. Despite their utility in various drug-development programs in academic research and the pharmaceutical industry, methods for the synthesis of this class of compounds and functionalization of 7-azaindole scaffolds remain limited [9]. Although the literature enumerates various

An intramolecular inverse electron demand Diels–Alder approach to annulated α-carbolines

• Zhiyuan Ma,
• Feng Ni,
• Grace H. C. Woo,
• Sie-Mun Lo,
• Philip M. Roveto,
• Scott E. Schaus and
• John K. Snyder

Beilstein J. Org. Chem. 2012, 8, 829–840, doi:10.3762/bjoc.8.93

• are also known [62][63][64]. In addition, cycloadditions of 3-vinyl-7-azaindole have also been used to close the pyridine ring [65], as have intramolecular dipolar cycloadditions of 2-azidoindole derivatives [66], and intramolecular cycloadditions of carbodiimides [67][68]. We had envisioned that a