Copper-Catalyzed Trifluoromethylation of Aryl and Vinyl Boronic Acids with An Electrophilic Trifluoromethylating Reagent

Abstract

A copper-catalyzed trifluoromethylation of aryl- and alkenylboronic acids with Togni's reagent was described. The reaction proceeded in good to excellent yields for a range of different substrates including heteroarylboronic acids and substrates with a variety of functional groups under mild reaction conditions.

Recent progress in the trifluoromethylation of alkenes with Togni's reagents

“…[4][5][6][7][8][9] Several years ago, Togni and co-workers 10 reported a conceptually new family of formally electrophilic CF 3 transfer reagents based on a cyclic hypervalent iodine(III) core, the most successful ones being Togni's reagents 1 and 2 (Scheme 1). These reagents are employed in the trifluoromethylation of phosphorus-, carbon-and oxygen-centered nucleophiles such as phosphines, 11 α-nitro-and β-keto-esters, 12,13 phosphorothioates, 14 aromatics, 15 alcohols, 16 sulfonic acids, 17 hydrogen phosphates, 18 aldehydes, 19 phenols, 20 arylboronic acids, 21 and quinones 22 . …”

Regioselective trifluoromethylation of N-heteroaromatic compounds using trifluoromethyldifluoroborane activator

“…Most current processes for accessing CF 3 containing molecules are performed by carboxy or trichloromethyl group substitution using hazardous fluorinating reagents under harsh reaction conditions 6 . Cross-coupling reactions between organohalides [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] or boronic acids (or their esters) [25][26][27][28][29][30][31][32][33][34] and trifluoromethylating reagents are another common approach. Although CF 3 groups can be regioselectively introduced to aromatic rings in cross-coupling reactions, requirement of multiple steps for the preparation of aryl halides and boronic acids/esters and generation of stoichiometric amounts of metal salts decrease synthetic efficiency.…”

Recent advances in green fluorine chemistry

“…In 2011, Xu et al 61 and Liu et al 62 reported two similar methods for trifluoromethylation of aryl boronic acids (Figure 28). Umemoto and Togni reagents were used as electrophilic CF 3 sources.…”