Cu-Facilitated C−O Bond Formation Using N-Hydroxyphthalimide: Efficient and Selective Functionalization of Benzyl and Allylic C−H Bonds
摘要:
A highly efficient protocol for the benzyl or allylic C-H functionalization of simple hydrocarbons has been developed using stoichiometric amounts of N-hydroxyphthalimide and Phl(OAc)(2) in the presence of CuCl catalyst. The reaction was revealed to proceed via a radical pathway, in which phthalimide N-oxyl (PINO) radical plays a dual role, serving as a catalytic hydrogen abstractor from hydrocarbons as well as a stoichiometric reagent to couple with the resultant alkyl radicals.
Catalytic <i>Ortho</i>-Acetoxylation of Masked Benzyl Alcohols via an <i>Exo</i>-Directing Mode
作者:Zhi Ren、Jonathan E. Schulz、Guangbin Dong
DOI:10.1021/acs.orglett.5b01098
日期:2015.6.5
A Pd-catalyzed ortho-acetoxylation of masked benzyl alcohols to synthesize various 2-hydroxyalkylphenol derivatives is reported. The 2,6-dimethoxyl benzaldoxime proved to be an efficient exo-type directing group for arene (sp(2)) CH functionalization. Two strategies were demonstrated to remove the directing group through N-O and C-O bond cleavages. A high catalyst turnover (>1000) was obtained to illustrate the practicality of this method.