alkyl ethers has been developed, achieving the challenging tertiary C(sp3)–SCF3 coupling under redox‐neutral conditions. The synergism of organophotocatalyst 4CzIPN and BINOL‐based phosphorothiols can site‐selectively cleave tertiary sp3 C(sp3)–O etherbonds in complex molecules initiated by a polarity‐matching hydrogen‐atom‐transfer (HAT) event. The incorporation of several competing benzylic and methine
by Pd-catalyzed C(sp3)–H bond functionalization was developed. Using a bidentate directing group, the direct and selective introduction of a SCF3 moiety was possible on a range of amides with remarkable selectivity for C(sp3)-centers with an electrophilic SCF3 source and pivalic acid as an additive. This work constitutes an example of the unactivated C(sp3)–SCF3 bond formation by C–Hactivation offering
and Lu's reagent 1 a being the most reactive and Billard's reagent 1 h being the least reactive electrophile. While the observed electrophilic reactivities (E) of the amido‐derived trifluoromethylthiolating reagents correlate well with the calculated Gibbs energies for heterolytic cleavage of the X−SCF3 bonds (Tt+DA), the cumol‐derivedreagents 1 f and 1 g are more reactive than expected from the thermodynamics
Palladium-Catalyzed Trifluoromethylthiolation of Aryl C–H Bonds
作者:Chunfa Xu、Qilong Shen
DOI:10.1021/ol5006533
日期:2014.4.4
A method for monotrifluoromethylthiolation of arenes via palladium-catalyzed directed C–H bond activation was described. The reaction was compatible with a variety of functional groups. Initial mechanistic studies disclosed that the turnover limiting step of the catalytic cycle did not involve C–H activation.