Gold-Catalyzed Carbene Transfer to Alkynes: Access to 2,4-Disubstituted Furans
作者:Søren Kramer、Troels Skrydstrup
DOI:10.1002/anie.201200307
日期:2012.5.7
example of a gold‐catalyzed intermolecular addition of carbon ylides to terminal alkynes is reported (see scheme; DCE=dichloroethane, Tf=trifluoromethanesulfonyl). Subsequent intramolecular trapping of the generated gold carbene completes a formal [3+2] cycloaddition, which represents a novel synthesis of 2,4‐disubstituted furans.
The electrode reaction taking place at the first reduction step involves cleavage of the carbon–sulfurbond, resulting in formation of acetophenone and the corresponding thiols in good yields even in an acetonitrile solution containing no proton donor. The second reduction step corresponds to the reduction of the acetophenone produced.
Kinetic Study on the Reaction of (Arylthio)trimethylsilanes with Phenacyl Bromide Giving Aryl Phenacyl Sulfides and Bromotrimethylsilane
作者:Seizi Kozuka、Tetsuji Higashino、Takuro Kitamura
DOI:10.1246/bcsj.54.1420
日期:1981.5
A kinetic study has been conducted on the reactions of (arylthio)trimethylsilanes with phenacyl bromide giving aryl phenacyl sulfides and bromotrimethylsilane. Remarkably large positive substituent effect (ρ=+2.2) and large negative entropy of activation were observed for the reaction. A mechanism involving 5-coordinated silicon intermediate prior to the rate-determining heterolysis of the Si–S bond
Visible light mediated reductions of ethers, amines and sulfides
作者:Timothy M. Monos、Gabriel Magallanes、Leanne J. Sebren、Corey R.J. Stephenson
DOI:10.1016/j.jphotochem.2016.05.014
日期:2016.9
Visible light-mediated photoredox catalysis enables the chemoselective reduction of activated carbon–heteroatom bonds as a function of reduction potential. The expansion of the scope of C–X bond reductions towards less activated motifs, such as ethers, amines and sulfides, is important to both organic synthesis and macromolecular degradation method development. In the present report, exploration of
Copper-Catalyzed Synthesis of α-Thioaryl Carbonyl Compounds Through SS and CC Bond Cleavage
作者:Liang-Hua Zou、Daniel L. Priebbenow、Long Wang、Jakob Mottweiler、Carsten Bolm
DOI:10.1002/adsc.201300566
日期:2013.9.16
α‐thioaryl esters employing copper acetate (hydrate) as catalyst and readily accessible diaryl disulfides and β‐diketones (or β‐keto esters) has been developed. Both alkyl‐ and aryl‐substituted carbonylcompounds can be prepared.