A Carbene Strategy for Progressive (Deutero)Hydrodefluorination of Fluoroalkyl Ketones
作者:Xiaolong Zhang、Xinyu Zhang、Qingmin Song、Paramasivam Sivaguru、Zikun Wang、Giuseppe Zanoni、Xihe Bi
DOI:10.1002/anie.202116190
日期:2022.2.7
A carbene strategy for the sequential (deutero)hydrodefluorination of fluoroalkyl ketones is reported. This method allowed for the controllable preparation of difluoroalkyl- and monofluoroalkyl ketones from aryl- and alkyl-substituted perfluoroalkyl ketones in high yield with excellent functional group tolerance.
(2) with a slope of unity over a wide range (108 in reactivity) of substituents from p-MeO to unsubstituted derivatives. The substituent effect on the solvolysis of 1 should be closer to that on the solvolysis of 2, rather than to the σ+ substituent effect. The ρ value for this system was estimated to be identical to the value of −6.3 assigned for 2, and the r value in the LArSR correlation to be comparable
Defluorinative Carboimination of Trifluoromethyl Ketones
作者:Xiaolong Zhang、Yongquan Ning、Zhaohong Liu、Shuang Li、Giuseppe Zanoni、Xihe Bi
DOI:10.1021/acscatal.2c02434
日期:2022.8.5
intramolecular cascade process by integrating successive cleavage of the C–Fbond and formation of C–C and C═N bonds on a single molecule entity, which differs relevantly from the stepwise mechanism of reported carbodefluorination of CF3 groups. Mechanistic studies disclose that silver catalysis plays a critical role, particularly in the stages of C–Fbondcleavage and aza-Claisen rearrangement.
Treatment of arylketene bis(methylthio)acetal monoxide with trifluoromethanesulfonic anhydride leads to ring-closure to afford 2-methylthiobenzo-[b]thiophene in high yield. The reaction is useful for synthesizing multisubstituted benzo[b]thiophenes.