Chemicals from Alkynes with Palladium Catalysts

Sequentially Palladium-Catalyzed Processes in One-Pot Syntheses of Heterocycles

“…Related to these results, Balalaie and coworkers published a facile entry to alkynoyl ortho-iodo anilides using the well-established Ugi four-component reaction [55]. Over the past decades, the Sonogashira alkynylation has turned out to be the most versatile catalytic synthesis of internal alkynes starting from (hetero)aryl or vinyl halides and terminal acetylenes [42,[57][58][59][60][61][62]. Most Sonogashira reactions are bimetallically catalyzed by palladium and copper complexes and, therefore, this unique catalyst system has also been shown to be suitable for CuAAC (Cu-catalyzed alkyne-azide cycloaddition) [63][64][65][66][67][68][69], eventually, in a sequential or consecutive fashion.…”

Light on Unsaturated Hydrocarbons – “Gotta Heterofunctionalize Them All”

“…The NCR can then be added intramolecularly to the alkene to form the hydroamination product through a 5-exo-trig cyclization. Ultimately, the final protonation is assured by CHCl 3 . This method presents good functional-group compatibilities and yields of up to 88 %, as shown in Scheme 3.…”

“…A proposed mechanism has been reported for this reaction (Scheme 17), and the authors suggested that the excited ruthenium catalyst is first reduced by the tetramethylethylenediamine (TMEDA, NR 3 Another approach has been proposed by Koike, Akita, and coworkers, who reported the first aminotrifluoromethylation of alkenes (Scheme 18). [32] From the electrophilic trifluoromethylating reagent CF 3 (Scheme 19). This species can be further added to alkene 85 to provide the sp 3 C-centered radical 86, which can be converted to cation 87 through the reduction of the photocatalyst.…”

Cross‐coupling reactions using porous multipod Cu2O microcrystals as recoverable catalyst in aqueous media

“…[1][2][3][4][5][6] Among these methods, Sonogashira coupling reactions of terminal acetylenes with aryl halides are the most popular. [7,8] The typical Sonogashira reactions are performed with palladium (0) catalyst and copper (I) co-catalyst in organic solvents using a suitable base.…”