N-heterocyclic carbene-catalysed pentafluorophenylation of aldehydes

Abstract

N-heterocyclic carbenes have been utilized as highly efficient organocatalysts to catalyse multifluorophenylation of aldehydes with fluorinated aryltrimethylsilanes to afford the corresponding adducts in 49–99% yields.

Reactions of Bifunctional Perfluoroarylsilanes with Activated C–F Bonds in Perfluorinated Arenes

“…15 Both trimethylsilyl sites reacted with aromatic aldehydes to provide diols having the tetrafluorophenylene skeleton. 16 However, reactions of p -C 6 F 4 (SiMe 3 ) 2 with fluorinated compounds, which may exploit the π-electron system associated with fluorine atoms, have not been reported. In the present study, we suggest synthetic methods for introducing a perfluorophenylene moiety into perfluoroarenes and investigate reactions of several perfluoroarenes containing electron-withdrawing substituents with p -C 6 F 4 (SiMe 3 ) 2 .…”

Nucleophilic fluoroalkylation/cyclization route to fluorinated phthalides

“…The reactions of 2-cyanobenzaldehyde ( 2 ) with organosilicon compounds (R F –SiMe 3 ) proceeded cleanly by the use of KF (conditions A) or Et 3 N (conditions B). As a consequence, pentafluoroethyl, heptafluoropropyl, and pentafluorophenyl [ 24 – 25 ] groups were successfully installed at the C3-position of phthalides 1b–d .…”

Transition Metal Catalyst‐Free, Base‐Promoted 1,2‐Additions of Polyfluorophenylboronates to Aldehydes and Ketones

“…Fore xample,i n1 999, Knochel and co-workers [24] used fluorinated aryl bromides to perform pentafluorophenylation of aldehydes (Scheme 1a). More recently,L am and coworkers [25] used ac opper catalyst (Scheme 1b)a nd Gu and co-workers [26] (Scheme 1b)u sed an N-heterocyclic carbene (NHC) organocatalyst to obtain fluorinated aryl carbinols using polyfluorophenyl trimethylsilane as an ucleophile for the addition to aldehydes.I n2 015, Huang and co-workers [27] (Scheme 1c)reported aMg-mediated polyfluoroaryl addition to aldehydes.Although some advancements in this field have been reported, these methods suffer from the requirement for highly flammable Grignard reagents,t ransition metals or NHC catalysts.Moreover,methods reported by Lam and coworkers and Gu and co-workers are limited to pentafluorophenyl trimethylsilane or 1,4-bis (trimethylsilyl) tetrafluorobenzene as substrates.…”