Au-catalyzed intramolecular hydroalkoxylation of gem-difluorinated alkynols
摘要:
The intramolecular hydroalkoxylation of gem-difluorinated alkynols was found possible under Au catalysis, allowing for the preparation of a series of fluorinated heterocycles. The nature of the solvent was found to be especially critical in the cyclization of gem-difluorohomopropargylic alcohols as it dictated whether the resulting 2,3-dihydrofuran underwent subsequent aromatization to the corresponding furan or not.
Selective Synthesis of Fluorinated Furan Derivatives via AgNO<sub>3</sub>-Catalyzed Activation of an Electronically Deficient Triple Bond
作者:Satoru Arimitsu、Gerald B. Hammond
DOI:10.1021/jo701616c
日期:2007.10.1
The transition metal-catalyzed direct activation of electron deficient triple bonds was investigated by using the combined electron withdrawing effects of two fluorine atoms to modulate the electronic density of the triple bond. With use of catalytic amounts of AgNO3 (10 mol %) the synthesis of substituted 3,3-difluoro-4,5-dihydrofurans from gem-diflou rohomopropargyl alcohols occurred in excellent NMR yields. Treatment of these dihydrofurans with SiO2 or Pd/H-2 yielded the corresponding 3-fluorinated furans and 3,3-difluorotetrahydrofurans.
Au-catalyzed intramolecular hydroalkoxylation of gem-difluorinated alkynols
作者:Jean-Denys Hamel、Jean-François Paquin
DOI:10.1016/j.jfluchem.2018.09.009
日期:2018.12
The intramolecular hydroalkoxylation of gem-difluorinated alkynols was found possible under Au catalysis, allowing for the preparation of a series of fluorinated heterocycles. The nature of the solvent was found to be especially critical in the cyclization of gem-difluorohomopropargylic alcohols as it dictated whether the resulting 2,3-dihydrofuran underwent subsequent aromatization to the corresponding furan or not.
Supported gold nanoparticles catalyzed cis-selective semihydrogenation of alkynes using ammonium formate as the reductant
作者:Shengzong Liang、Gerald B. Hammond、Bo Xu
DOI:10.1039/c6cc01318j
日期:——
nanoparticles with low loading (0.5 mol %) are able to semihydrogenate non-fluorinated and gem-difluorinated alkynes to cis-alkenes with high selectivity, using cost-effective and easy-to-handle ammoniumformate as...