Synthesis of 1-(Difluoromethyl)alk-1-enes via Palladium-Catalyzed SN2'-Type Substitution Reaction of Difluoromethylated Allylic Phosphates with 1,3-Dicarbonyl Compounds and Imides

Silver-Catalyzed Cascade Radical Isonitrile Insertion/Defluorinative Cyclization: Direct Synthesis of 4-CF2H-2-Phosphinoyl-quinolines

A novel silver-catalyzed cascade radical isonitrile insertion and defluorinative cyclization have been developed to synthesize CF2H- and phosphinoyl-containing quinolines from ortho-isocyanyl α-trifluoromethylstyrenes. The reaction proceeded under redox-neutral conditions and allowed the construction of a highly attractive quinoline ring system, with the simultaneous formation of the CF2H group and introduction of various phosphinoyl groups in a single transformation, showing operational simplicity, a wide substrate scope, good tolerance for functional groups, and remarkable atom-/stepeconomy. Mechanistic studies indicated that the reaction is likely to involve the participation of P-centered radicals and key carbanion intermediates.

Organophosphates as Versatile Substrates in Organic Synthesis

This review summarizes the applications of organophosphates in organic synthesis. After a brief introduction, it discusses cross-coupling reactions, including both transition-metal-catalyzed and transition-metal-free substitution reactions. Subsequently, oxidation and reduction reactions are described. In addition, this review highlights the applications of organophosphates in the synthesis of natural compounds, demonstrating their versatility and importance in modern synthetic chemistry.

Aerobic Allylic Amination Catalyzed by a Pd(OAc)2/P(OPh)3 System with Low Catalyst Loading

A Pd(OAc)₂/P(OPh)₃ combination catalyzed Tsuji-Trost-type allylic amination under aerobic conditions. Both aromatic and aliphatic secondary amines were transformed into the corresponding allylic amines with a tiny amount of the catalyst system (typically 0.02 mol % Pd), only when allylic phosphates were employed as electrophiles. Other typical electrophiles, such as allylic acetate and carbonate, were marginally reactive. A Pd(0) complex, Pd[P(OPh)₃]₃, formed in situ was suggested as an active species by mechanistic experiments.

Synthesis of difluoromethylated diarylmethanes via Fe(OTf)3-catalyzed Friedel-Crafts reaction of 2,2-difluoro-1-arylethyl phosphates

The Fe(OTf)₃-catalyzed Friedel-Crafts reaction of 2,2-difluoro-1-arylethyl phosphates with electron-rich (hetero)arenes afforded difluoromethylated diarylmethanes. Control experiments showed that Fe(OTf)₃ behaves as the Lewis acid, and that the phosphate leaving group and o- or p-alkoxy substituents on the substrates are necessary for the Fe(OTf)₃-catalyzed reaction to proceed under mild conditions.