Photocatalytic Three-Component Reductive Coupling Synthesis of gem-Difluorohomoallyl Secondary Amines

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 23, 2025

gem-Difluorohomoallyl amines, an important class of gem-difluoroalkenes, are prevalent moieties in many bioactive compounds. However, limited methods suitable for the synthesis this type compound containing secondary amines. Here, we display a photocatalytic multicomponent protocol gem-difluoroalkenes which makes use readily available materials: arylamines, alkyl aldehydes, and α-trifluoromethyl alkenes. Moreover, ketones amines also substrates. Preliminary mechanistic experiments indicate that key α-amino radical was involved, generated from reduction situ-formed imines (or iminium ions) by reduced photocatalyst. Subsequent addition to alkenes β-F elimination deliver desired products.

Language: Английский

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Mild [3 + 3] Annulation of (Trifluoromethyl)alkenes with Thioureas Enabled by Chemoselective Defluorinative Amination: Synthesis of 6-Fluoro-3,4-dihydropyrimidine-2(1H)-thiones

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: 90(4), P. 1538 - 1548

Published: Jan. 21, 2025

The chemoselective defluorinative [3 + 3] annulation of (trifluoromethyl)alkenes with thioureas is reported. This protocol affords various attractive 6-fluoro-3,4-dihydropyrimidine-2(1H)-thiones in high yields, features transition-metal free, mild conditions, efficient, operationally simple and gram-scalable, tolerates diverse useful functional groups.

Language: Английский

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Photocatalytic 1,3-Difluoroalkylcarboxylation of Alkenes by Triple Kinetic-Controlled Radical Self-Ordering

Chemical Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A transition-metal-free protocol for the unsymmetrical radical 1,3-difunctionalization of alkenes has been established first time in form 1,3-difluoroalkylcarboxylation by a photocatalytic three-component reaction allyl formates, trifluoroacetanilides, and cesium formate. This employs formate as carboxylating reagent trifluoroacetanilide difluoroalkylating via C-F bond activation. As result, series previously inaccessible difluorinated adipic acid derivatives can be easily efficient prepared. Mechanism studies reveal that triple kinetic-controlled self-ordering is key to this unique reaction. sorting involves fast initiation CO2 anion its chemoselective addition reduction, followed slow generation fluoroalkyl chemo-/regioselective addition. Notably, strategy also suitable cyclic through diastereoselectively constructing two or three consecutive stereocenters.

Language: Английский

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Photoredox Catalytic Defluoroalkylation of gem-Difluoroalkenes with Secondary N-Alkylanilines via C–F/C–H Coupling

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 22, 2024

To provide fluorinated allylamines, a visible-light photocatalytic C–F/C–H coupling of easily accessible gem-difluoroalkenes and secondary N-alkylanilines was described. The protocol proceeded under mild conditions, with excellent functional group compatibility broad scope including complex natural product derivatives, thus providing green method for the preparation high-value functionalized monofluoroalkenes. Mechanistic studies elucidated photoredox catalyzed radical–radical pathway.

Language: Английский

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Tunable base-controlled chemoselective synthesis of trifluoromethyl-containing N-substituted benzimidazole-2-thiones and monofluorinated 4H-benzo[4,5]imidazo[2,1-b][1,3]thiazine

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 26, 2024

A base-controlled synthesis of N -β-CF 3 -substituted 2 H -benzo[ d ]imidazole-2-thiones and 2-fluoro-4 -benzo[4,5]imidazo[2,1- b ][1,3]thiazines via hydroamination or defluorinative cyclizations α-CF -styrenes with 2-mercaptobenzimidazole was developed.

Language: Английский

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