122801-61-0Relevant articles and documents
Iron-Catalyzed Room Temperature Cross-Couplings of Bromophenols with Aryl Grignard Reagents
Xu, Li-Chen,Liu, Kun-Ming,Duan, Xin-Fang
supporting information, p. 5421 - 5427 (2019/11/14)
Herein we report a room temperature Fe-catalyzed coupling reaction of various bromophenols with aryl Grignard reagents, which exhibits a wide substrate scope and high functional group tolerance. For the first time, the combination of simple Fe(acac)3/PBu3/Ti(OEt)4 has been used as an effective catalyst for the biaryl couplings of bromophenols or their Na or K salts with debromination and etherification side reactions being well suppressed. Various biphenols including natural product garcibiphenyl C as well as pharmaceutical diflunisal and its ethyl ester were facilely synthesized using the present protocol. (Figure presented.).
Synthesis of 2,2′-biphenols through direct C(sp2)-H hydroxylation of [1,1′-biphenyl]-2-ols
Duan, Shitao,Xu, Yuanshuang,Zhang, Xinying,Fan, Xuesen
supporting information, p. 10529 - 10532 (2016/09/02)
A novel synthesis of diversely substituted 2,2′-biphenols through Pd(ii)-catalyzed, tBuOOH-oxidized, and hydroxyl-directed C(sp2)-H hydroxylation of [1,1′-biphenyl]-2-ols has been developed. Notably, this finding is distinct from previous reports in which [1,1′-biphenyl]-2-ols underwent an intramolecular C-H activation and C-O bond formation to afford dibenzofurans under the promotion of Pd(ii) but in the absence of tBuOOH.
Titania-promoted carboxylic acid alkylations of alkenes and cascade addition-cyclizations
Manley, David W.,McBurney, Roy T.,Miller, Phillip,Walton, John C.,Mills, Andrew,O'Rourke, Christopher
, p. 1386 - 1398 (2014/03/21)
Photochemical reactions employing TiO2 and carboxylic acids under dry anaerobic conditions led to several types of C-C bond-forming processes with electron-deficient alkenes. The efficiency of alkylation varied appreciably with substituents in the carboxylic acids. The reactions of aryloxyacetic acids with maleimides resulted in a cascade process in which a pyrrolochromene derivative accompanied the alkylated succinimide. The selectivity for one or other of these products could be tuned to some extent by employing the photoredox catalyst under different conditions. Aryloxyacetic acids adapted for intramolecular ring closures by inclusion of 2-alkenyl, 2-aryl, or 2-oximinyl functionality reacted rather poorly. Profiles of reactant consumption and product formation for these systems were obtained by an in situ NMR monitoring technique. An array of different catalyst forms were tested for efficiency and ease of use. The proposed mechanism, involving hole capture at the TiO2 surface by the carboxylates followed by CO2 loss, was supported by EPR spectroscopic evidence of the intermediates. Deuterium labeling indicated that the titania likely donates protons from surface hydroxyl groups as well as supplying electrons and holes, thus acting as both a catalyst and a reaction partner.
