57091-71-1

Upstream product

• 7755-70-6 2-(methylamino)benzaldehyde 
• 75-36-5 acetyl chloride 
• 57091-65-3 1,3,4-trimethyl-1,3-dihydro-benzo[b]azepin-2-one 
• 875-79-6 1,2-dimethylindole 
• 57091-67-5 N-Methyl-2-(2,3-dimethyl-4-oxo-1-hexenyl)-anilin 
• 552-89-6 2-nitro-benzaldehyde 
• 529-23-7 o-aminobenzaldehyde 
• 13493-47-5 N-(2-formylphenyl)acetamide 
• 74-88-4 methyl iodide 
• 57091-70-0 N-[2-((Z)-2,3-dimethyl-4-oxo-hex-1-enyl)-phenyl]-N-methyl-acetamide 

Relevant academic research and scientific papers

Visible-Light-Mediated Dearomatisation of Indoles and Pyrroles to Pharmaceuticals and Pesticides

Dearomatisation of indole derivatives to the corresponding isatin derivatives has been achieved with the aid of visible light and oxygen. It should be noted that isatin derivatives are highly important for the synthesis of pharmaceuticals and bioactive compounds. Notably, this chemistry works excellently with N-protected and protection-free indoles. Additionally, this methodology can also be applied to dearomatise pyrrole derivatives to generate cyclic imides in a single step. Later this methodology was applied for the synthesis of four pharmaceuticals and a pesticide called dianthalexin B. Detailed mechanistic studies revealed the actual role of oxygen and photocatalyst.

Aerobic C–C Bond Cleavage of Indoles by Visible-Light Photoredox Catalysis with Ru(bpy)32+

Photoredox catalysis with Ru(bpy)32+ (2,2′-bipyridine) has been used to enable the activation of oxygen in the aerobic C–C cleavage/oxygenation reaction of indoles. A number of indole substrates that contain various functional groups were successfully employed in the reaction to give a wide range of ortho-aminobenzaldehyde derivatives. These products can then be used as versatile building blocks for further synthetic modifications. Mechanistic studies suggest that the reaction proceeds through a radical pathway.

Visible Light Photocatalytic Aerobic Oxygenation of Indoles and pH as a Chemoselective Switch

An efficient chemodivergent strategy for visible light photocatalysis is developed. In the presence of a dicyanopyrazine-derived chromophore (DPZ) photocatalyst, aerobic photooxygenation of indoles could produce either isatins or formylformanilides in satisfactory yields by judiciously selecting inorganic salts or modulating the reaction pH. The current chemodivergent method is also effective with 2-substituted indoles, opening straightforward synthetic routes to valuable 2,2-disubstituted 3-oxindoles, formylformanilide derivatives, and benzoxazinones. Mechanistic investigations involving cyclic voltammetry studies further confirm that reaction pH influences the electrochemical properties of DPZ, thus affecting the oxidative pathway by which indoles are being transformed.

Dimethyldioxirane oxidation of n-substituted-2-methylindoles to indoxyls and bisindoxyls

Oxidation of 2-methylindoles 12a-f with dimethyldioxirane (DMD) revealed that N-unprotected 12b,f and protected N-carbamate 2-methylindole 12c afforded indoxyls 16b,c and o-(N-propionyl)aminobenzoic acid 17f as the main products, while N-alkyl- or N-aryl-2-methylindoles 12a,d,e gave 1,5′-diphenyl- 4′,5′-dihydro-3′H-spiro[indole-2,2′-pyrano[3,2-b]indol] -3(1H)-one (10), 2,3′-bisindolin-3-ones 13, dispiro[indole-2,2′- furan-5′,2″-indole]diones 14 or 2-[(3-oxoindolin-2-yl)methyl]-2- hydroxyindolin-3-ones 15. The structure of dimers 10, 13a,d,e, 14a,d and 15a,d followed from NMR measurements, X-ray diffraction analysis confirmed those structures of 13a,d,e, 14a,d and 15d, and some mechanistic implications are discussed.

Facile synthesis of 3-substituted and 1,3-disubstituted quinolin-2(1H)-ones from 2-nitrobenzaldehydes

2-Nitrobenzaldehydes were reduced with iron powder to 2-aminobenzaldehydes, which were reacted immediately with acyl chlorides to provide 2-carboxamidobenzaldehydes (1) with overall yields of 71-90 %. Reaction of 1 with base provided 3-substituted quinolin-2(1H)-ones with 63-97 % yields. Treatment of 1 with methyl iodide and base gave 1-methyl-3-substituted quinolin-2(1H)-ones with 82-95 % yields, whereas the treatment with isopropyl iodide gave 1-isopropyl-3-substituted quinolin-2(1H)-ones with 7-42 % yields.