Vanadium-Catalyzed Solvent-Free Synthesis of Quaternary α-Trifluoromethyl Nitriles by Electrophilic Trifluoromethylation
作者:Natalja Früh、Antonio Togni
DOI:10.1002/anie.201406181
日期:2014.9.26
The direct electrophilic trifluoromethylation of silyl ketene imines (SKIs) with hypervalent iodine reagents leads to the formation of quaternary α‐trifluoromethyl nitriles in good yields. This new reaction has been carried out with a variety of substituted SKIs under solvent‐free conditions using a vanadium(IV) catalyst (5 mol %). The corresponding products may be transformed into useful organofluorine
Copper-Catalyzed Aerobic Aliphatic C–H Oxygenation Directed by an Amidine Moiety
作者:Yi-Feng Wang、Hui Chen、Xu Zhu、Shunsuke Chiba
DOI:10.1021/ja305833a
日期:2012.7.25
A method for the oxygenation of tertiary C-H bonds of N-alkylamidines and N-(2-alkylaryl)amidines is described that utilizes the CuBr·SMe(2)/2,2'-bipyridine catalytic system under an O(2) atmosphere and provides dihydrooxazoles and 4H-1,3-benzoxazines. The oxygen atom is incorporated from atmospheric molecular oxygen during the present process.
Catalytic Carbonyl-Olefin Metathesis of Aliphatic Ketones: Iron(III) Homo-Dimers as Lewis Acidic Superelectrophiles
作者:Haley Albright、Paul S. Riehl、Christopher C. McAtee、Jolene P. Reid、Jacob R. Ludwig、Lindsey A. Karp、Paul M. Zimmerman、Matthew S. Sigman、Corinna S. Schindler
DOI:10.1021/jacs.8b11840
日期:2019.1.30
carbon-carbon bond formation. However, currently available synthetic protocols rely exclusively on arylketone substrates while the corresponding aliphatic analogs remain elusive. We herein report the development of Lewis acid-catalyzed carbonyl-olefin ring-closing metathesis reactions for aliphatic ketones. Mechanistic investigations are consistent with a distinct mode of activation relying on the in