Readily available alkylbenzenes as precursors for the one-pot preparation of buta-1,3-dienes under DDQ visible-light photocatalysis in benzotrifluoride

Abstract

Easily accessible alkylbenzenes are highly valuable starting materials and solvents in synthetic organic chemistry for production of pharmaceuticals, plastics, synthetic rubber, dyes, etc. Herein, by employing alkylbenzenes as precursors, an...

A photocatalyst-free method for the synthesis of 6-alkyl(aryl)phenanthridines under visible light irradiation

“…9 Likewise, in 2018, Sun and co-workers 10 described an amazing protocol based on the lone pair–π interactions in the synthesis of 6-alkylphenanthridines from biaryl oximes, triethylamine, and dimethylsulfoxide under irradiation by blue LEDs (Scheme 1b). 10 In continuation to these and our research on visible-light photocatalysis, 11 we describe here a novel and photocatalyst-free methodology for the synthesis of a series of 6-alkyl(aryl)phenanthridines from isocyanobiaryls and alkyl(aryl)sulfinates in ethyl lactate under blue-LED irradiation. Also, we report a possible reaction mechanism, vide infra .…”

Multiple-cycle photochemical cascade reactions

“…In 2022, the group of Natarajan unveiled a visible-light-induced oxidative dehydrogenation/homocoupling cascade reaction of alkylbenzenes 16 to synthesize buta-1,3-dienes 17 with good yields (up to 91% yield) (Scheme 6). 38 By using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as the organic photocatalyst and tert -butyl nitrite ( t BuONO) as the sacrificial oxidant, this protocol demonstrated good functional group tolerance and a broad substrate scope. Remarkably, this cascade reaction proceeds smoothly not only with simple substituted alkylbenzenes, but also with complex substrates such as 1-ethyl-4-methylcyclohex-1-ene and a heteroaryl substrate, delivering the desired products 17a and 17b with satisfactory outcomes.…”

Palladium-Catalyzed Regioselective Diarylation/Deamination of Homoallylamines: Modular Assembly of 1,1,4,4-Tetraaryl-1,3-butadienes

“…As shown in Figure , several representative TABD molecules have been successfully applied as fluorescent materials, stimuli response material, and chemical or biological sensors . The TABDs are traditionally prepared by reductive elimination of 1,4-diol, condensation of diarylpropene with benzophenone, and the homocoupling of disubstituted olefins . To date, the palladium-catalyzed Suzuki coupling reaction between 1,4-dibromo-diene and aryl boronic acid is the most straightforward route to access TABDs (Scheme , a). , Nonetheless, the structure diversity of this method is inherently restricted by the predefined stereochemistry of such a prefunctionalized dibromo-diene, and a mixture of coupling products are inevitable when halo-substituted (especially Br and I) boronic acids were employed.…”