863870-52-4

Upstream product

• 552-89-6 2-nitro-benzaldehyde 
• 253684-24-1 1-(2,2-dibromovinyl)-2-nitrobenzene 
• 167558-54-5 2-(2,2-dibromo-vinyl)-phenylamine 
• 98-80-6 phenylboronic acid 

Downstream Products

• 18434-12-3 1,2-diphenyl-1H-indole 
• 886853-72-1 2-(3,4-dimethoxyphenyl)-1-phenyl-1H-indole 
• 78945-61-6 1-phenyl-1H-indole-2-carboxylic acid methyl ester 
• 1240045-37-7 2-bromo-1-phenyl-1H-indole 

Relevant academic research and scientific papers

A highly selective tandem cross-coupling of gem-dihaloolefins for a modular, efficient synthesis of highly functionalized indoles

(Chemical Equation Presented) A highly efficient method of indole synthesis using gem-dihalovinylaniline substrates and an organoboron reagent was developed via a Pd-catalyzed tandem intramolecular amination and an intermolecular Suzuki coupling. Aryl, alkenyl, and alkyl boron reagents are all successfully employed, making for a versatile modular approach. The reaction tolerates a variety of substitution patterns on the aniline leading to indoles with group at C2-C7. The orthogonal approach of the sequential copper- and palladium-mediated synthesis of 1,2-diarylindoles exploited the wide availability of diverse organoboron reagents.

2-SUBSTITUTED INDOLES, THEIR PRECURSORS AND NOVEL PROCESSES FOR THE PREPARATION THEREOF

Disclosed are processes for the preparation of 2-substituted indole compounds wherein the 2-substituent comprises an R4 group, wherein R4 is selected from the group consisting of monocyclic aromatic, polycyclic aromatic, monocyclic heteroaromatic, polycyclic heteroaromatic, 1° alkyl, and alkenyl, all of which are optionally substituted at one or more substitutable positions with one or more suitable substituents, and wherein R4 is bonded to the 2-position of the indole ring via a C-C bond; the process comprising reacting an ortho-gem-dihalovinylaniline compound of the formula (I): wherein Halo comprises Br, Cl, or I; each of the one or more R1 is independently selected from the group consisting of H, fluoro, lower alkyl, lower alkenyl, lower alkoxy, aryloxy, lower haloalkyl, lower alkenyl, -C(O)O-lower alkyl, monocyclic or polycyclic aryl or heteroaryl moiety, or R1 is an alkenyl group bonded so to as to form a 4- to 20-membered fused monocycle or polycyclic ring with the indole ring; all of which are optionally substituted with one or more suitable substituents at one or more substitutable positions; R2 comprises H, alkyl, cycloalkyl, aryl, heteroaryl, aryl-loweralkyl-, or heteroaryl-loweralkyl-, all of which are optionally substituted at one or more substitutable positions with one or more suitable substituents; R3 comprises H, alkyl, haloalkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, heterocycle, aryl-(C1-6)alkyl-, or heteroaryl-loweralkyl-, all of which are optionally substituted at one or more substitutable positions with one or more suitable substituents; with an organoboron reagent selected from the group consisting of a boronic ester of R4, a boronic acid of R4, a boronic acid anhydride of R4, a trialkylborane of R4 and a 9-BBN derivative of R4; in the presence of a base, a palladium metal pre-catalyst and a ligand under reaction conditions effective to form the 2-substituted indole compound. Also disclosed are processes for the preparation of ortho-gem-dihalovinylaniline compounds. Novel compounds prepared by the processes and novel uses of the compounds are likewise disclosed.

Pd-catalyzed tandem C-N/C-C coupling of gem-dihalovinyl systems: A modular synthesis of 2-substituted indoles

(Chemical Equation Presented) 2-Substituted indoles were synthesized via a Pd-catalyzed tandem C-N/Suzuki-Miyaura coupling from readily prepared ortho-gem-dihalovinylanilines. Optimal conditions used a Pd(OAc) 2/S-Phos catalyst in the presence of K3PO 4·H2O and an organoboron reagent, which included boronic acids, esters, alkyl 9-BBN derivatives, and trialkylboranes. Yields of the desired indoles were good to excellent using low catalyst loadings (typically 1 mol %).