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An efficient copper-catalyzed direct C(sp2)-H/C(sp3)-H coupling reaction of aza-aromatic rings with fluoroalcohols is developed. A variety of useful building blocks including hydroxyfluoroalkylated aniline, pyrrole, and indole derivatives bearing a quaternary carbon center could be constructed with high regioselectivity and good to excellent yields under very mild reaction conditions. The reaction is believed to undergo a fluoroalcohol oxidation and to follow an electronic addition reaction pathway.

A cobalt-catalyzed site-selective functionalization of aniline derivatives with hexafluoroisopropanol, which enables the synthesis of a wide array of fluoroalkylated anilines, a class of highly valuable building blocks for further preparation of fluorinated functional products, is reported. The developed transformation proceeds with operational simplicity, use of earth-abundant metal catalyst, broad substrate scope, good functional group tolerance, and mild reaction conditions.

C-Hydroxyalkylation of primary arylamines by highly electrophilic polyfluorocarbonyl compounds results from the direct reaction of the initial reagents and is competitively inhibited by equilibrium N-hydroxyalkylation.The presence of steric hindrances to

Solvolysis rates of ArC(CF3)2OTs in CF3CO2H give an excellent correlation log k = -10.7?+-8.69, and a point for the p-Me2N compound derived from the rate of the p-nitrobenzoate also fits this correlation, giving a span of 1E19 in reactivity.Limiting values of ρ+ of -10 to -12 for generation of benzylic cations in the gas phase and solution have been reached.Rate ratios k(ArCH(OTs)CF3)/k(ArC(CF3)2OTs) increase from 2.4 to 54 with decreasing aryl donor power; these k(H)/k(CF3) ratios are much less than typical values of 1E6 in more stabilized systems.Displacement of the p-MeO group occurs in solvolysis of p-MeOC6H4C(CF3)2OTs (9) in EtOH and CD3OH.Trifluoroacetolysis of ArC(OTs)(CF3)CN (Ar = p-Tol (13) and Ph) gives ρ+ = -12.1, and for 13 in different solvents the reactivity is greater than p-TolCH(OTs)CF3 by factors of 8.6 to 175.This is the first observation of k(CN)/k(H) ratios greater than 1.0.All these results, plus the rather modest dependence of the rates on solvent polarity (m = 0.76 for 9 and 0.66 for 13), are interpreted in terms of carbocationic transition states and intermediates in which the charge is largely delocalized onto the aryl group.

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