1131890-87-3

Upstream product

• 1749-19-5 phenyl(1-phenylethylidene)amine 
• 1131890-85-1 2-chloro-5-methylphenyl trifluoromethanesulfonate 
• 1131890-93-1 2-chloro-5-methylphenyl nonaflate 
• 108-90-7 chlorobenzene 
• 264912-27-8 1-bromo-2-(phenylethynyl)-4-methylbenzene 
• 13141-44-1 4-methyl-2-(phenylethynyl)aniline 
• 98-80-6 phenylboronic acid 
• 66003-76-7 Diphenyliodonium triflate 
• 583-70-0 1-bromo-2,4-dimethylbenzene 
• 27561-50-8 1-bromo-2-(bromomethyl)-4-methylbenzene 
• 538-51-2 benzylidene phenylamine 
• 95-68-1 2,4-Xylidine 
• 108-86-1 bromobenzene 
• 25078-04-0 N-(2,4-dimethylphenyl)aniline 

Relevant academic research and scientific papers

Regioselective three-component synthesis of 1,2-diarylindoles from cyclohexanones, α-hydroxyketones and anilines under transition-metal-free conditions

A facile method for the one-pot synthesis of 1,2-diarylindoles under transition-metal-free conditions is described. Cyclohexanones were used as the aryl sources via the dehydrogenative aromatization process. One C-C and two C-N bonds were selectively formed via a domino reaction. This protocol provides a convenient approach for the construction of valuable bioactive 1,2-diarylindoles from readily available cyclohexanones, α-hydroxyketones and anilines.

Selective arylation/annulation cascade reactions of 2-alkynylanilines with diaryliodonium salts

An efficient Cu catalyzed selective arylation/annulation cascade reaction of 2-alkynylanilines with diaryliodonium salts was developed. This reaction was selective to N-arylation instead of C-arylation, which provides a simple synthetic method for N-aryl indoles.

tBuOK-Promoted Cyclization of Imines with Aryl Halides

A transition-metal-free indole synthesis using radical coupling of 2-halotoluenes and imines via the later-stage C-N bond construction was reported for the first time. It includes an aminyl radical generation by C-H cleaving addition of 2-halotoluenes to imines via the carbanion radical relay and an intramolecular coupling of aryl halides with aminyl radicals. One standard condition can be used for all halides including F, Cl, Br, and I. No extra oxidant or transition metal is required.

Transition-Metal-Free Synthesis of 1,2-Disubstituted Indoles

Herein, we report a new transition-metal-free robust and cost-effective method for synthesis of 1,2-disubstituted indoles from easily available unactivated (i.e. without EWG, PPh3 or SiR3 groups) tertiary amides. Scope of synthetic applicability of the presented protocol was shown on 23 examples of 1,2-disubstituted indoles with different substitution patterns obtained in good to excellent yields. The reported method turned out to be especially effective for synthesis of N-arylated 2-CF3-indoles. Moreover, this approach can be performed in a one-pot two-step manner directly from commercially available secondary amines. Mechanistic studies showed that acyl transfer might be an important step in the course of the reaction. Viability of the presented approach for benzofurans and benzothiophenes synthesis was also discussed.

Access to Indole Derivatives from Diaryliodonium Salts and 2-Alkynylanilines

An efficient, environmentally friendly, and operationally simple procedure to 1,2-disubstituted indoles from 2-alkynylanilines and diaryliodonium salts has been developed. This reaction proceeds smoothly under metal-free conditions. The products obtained could be transferred into 3,3′-diindolylmethane with DMSO catalyzed by palladium. The isotopic label experiments indicated that the methylene group in 3,3′-diindolylmethane is derived from DMSO. The diverse indoles were obtained in up to 90% yield for 28 examples.

One-pot approach to 1,2-disubstituted indoles via Cu(II)-catalyzed coupling/cyclization under aerobic conditions and its application for the synthesis of polycyclic indoles

A straightforward assembly of 1,2-disubstituted indoles has been developed through a Cu(II)-catalyzed domino coupling/cyclization process. Under aerobic conditions, a wide range of 1,2-disubstituted indole derivatives were efficiently and facilely synthesized from 2-alkynylanilines and boronic acids. 2-(2-Bromoaryl)-1-aryl-1H-indoles, which were selectively generated in one pot under the Cu catalysis, afforded the indolo[1,2-f]phenanthridines via Pd-catalyzed intramolecular direct C(sp2)-H arylation. The one-pot tandem approaches to the polycyclic indole derivatives were also successfully achieved.

BippyPhos: A single ligand with unprecedented scope in the Buchwald-Hartwig amination of (hetero)aryl chlorides

Over the past two decades, considerable attention has been given to the development of new ligands for the palladium-catalyzed arylation of amines and related NH-containing substrates (i.e., Buchwald-Hartwig amination). The generation of structurally diverse ligands, by research groups in both academia and industry, has facilitated the accommodation of sterically and electronically divergent substrates including ammonia, hydrazine, amines, amides, and NH heterocycles. Despite these achievements, problems with catalyst generality persist and access to multiple ligands is necessary to accommodate all of these NH-containing substrates. In our quest to address this significant limitation we identified the BippyPhos/[Pd(cinnamyl)Cl]2 catalyst system as being capable of catalyzing the amination of a variety of functionalized (hetero)aryl chlorides, as well as bromides and tosylates, at moderate to low catalyst loadings. The successful transformations described herein include primary and secondary amines, NH heterocycles, amides, ammonia and hydrazine, thus demonstrating the largest scope in the NH-containing coupling partner reported for a single Pd/ligand catalyst system. We also established BippyPhos/ [Pd(cinnamyl)Cl]2 as exhibiting the broadest demonstrated substrate scope for metal-catalyzed cross-coupling of (hetero)aryl chlorides with NH indoles. Furthermore, the remarkable ability of BippyPhos/[Pd(cinnamyl)Cl] 2 to catalyze both the selective monoarylation of ammonia and the N-arylation of indoles was exploited in the development of a new one-pot, two-step synthesis of N-aryl heterocycles from ammonia, ortho- alkynylhalo(hetero)arenes and (hetero) aryl halides through tandem N-arylation/hydroamination reactions. Although the scope in the NH-containing coupling partner is broad, BippyPhos/[Pd(cinnamyl)Cl]2 also displays a marked selectivity profile that was exploited in the chemoselective monoarylation of substrates featuring two chemically distinct NH-containing moieties.

On-water, microwave-assisted, Pd-catalyzed synthesis of indoles from imines and o-difunctionalized arenes

Regioselectively substituted indoles are prepared by a Pd-catalyzed C-C/C-N bond-forming sequence from imines and o-dihaloarenes or o-haloarene sulfonates. The heterogeneous reaction as a suspension in water and under microwave heating offers important advantages in comparison with the conventional reaction in an organic solvent, among them, operational simplicity, the employment of KOH solutions instead of alkoxides, and a dramatic reduction of reaction times.

Modular synthesis of indoles from imines and o-dihaloarenes or o-chlorosulfonates by a Pd-catalyzed cascade process

A detailed study of the scope of a new Pd-catalyzed synthesis of indolesfrom 1,2-dihaloarenes and o-halobenzene sulfonates and imines is descri bed. The cascade reaction comprises an imine a-arylation ollowed by an intramolecular C-N bond-forming reaction promoted by the same Pd catalyst. The reaction with 1,2-dibromobenzene shows wide scope and allows the introduction of aryl, alkyl, and vinyl substituents at different positions of the five-membered ring of the indole. The regioselective synthesis of indoles substituted in the six-membered ring can be carried out by employing o-dihalobenzene derivatives with two different halogens, taking advantage of the different reactivities of I, Br, and Cl in oxidative addition reactions. This paper also introduces a method for the efficient cleavage of the N-t-butyl group, thus allowing for the preparation of N-H indoles through the same methodology. Finally, the reaction with o-halosulfonates has been studied. The best substrates are o-chlorononaflates, which lead to indoles in very high yield. The reaction is particularlyappropriate for the synthesis of the challenging 6-substituted indoles. In view of the availability of o-chlorophenols, which are direct precur sors of the chlorononaflates, this reaction represents an efficient entry into indoles substituted in the six-membered ring. The concept is illustrated by the preparation of a 4,6-disubstituted indole from naturally occurring anethole.