Oxidation of Secondary Benzylic Alcohols to Ketones by Activated Carbon–Molecular Oxygen System
作者:Yuki Sano、Takanori Tanaka、Masahiko Hayashi
DOI:10.1246/cl.2007.1414
日期:2007.12.5
A variety of benzylic alcohols were oxidized to the corresponding carbonyl compounds selectively in the presence of activated carbon under molecular oxygen atmosphere. This process does not require...
Enantioselective alkynylation of trifluoromethyl ketones catalyzed by chiral Schiff bases in the presence of Me2Zn afforded the corresponding trifluoroalkynyl alcohols in up to 66 % ee.
One-Pot Synthesis of 3,4-Disubstituted Coumarins under Catalysis of Mn3O4 Nanoparticles
作者:Huayin Sun、Yonghui Zhang、Fengfeng Guo、Yizhe Yan、Changfeng Wan、Zhenggen Zha、Zhiyong Wang
DOI:10.1002/ejoc.201101578
日期:2012.1
The one-potsynthesis of 3,4-disubstitutedcoumarins from substituted 2-(hydroxymethyl)phenols with β-keto esters catalyzed by Mn3O4nanoparticles was developed. A series of 3,4-disubstitutedcoumarin derivatives were obtained in good yields.
the reaction occurs via triplet excited state. Photooxygenation of 2 and 3 in cyclohexane resulted in oxidative cleavage to give benzoic acid and acetic acid, respectively, in addition to 2,6-di-t-butylbenzoquinone (13). In triethylamine 2 and 3 were photoreduced to yield 3,5-di-t-butyl-4-hydroxybenzhydrol (14) and the corresponding pinacol 16, respectively. Mechanisms involving triplet excited state