A new catalytic aerobicoxidation of alcohols to aldehydes under green conditions was developed (room temperature and pressure, water solution, open vials). The water-soluble platinum(II) tetrasulfophthalocyanine (PtPcS) catalyst showed the best selectivity for carbonyl derivatives, and in particular for α,β-unsaturated alcohols; the reactions are slow.
The Thermal Sulfenate−Sulfoxide Rearrangement: A Radical Pair Mechanism
作者:Jérôme Amaudrut、Olaf Wiest
DOI:10.1021/ja9940928
日期:2000.4.1
formation a radical pair by homolytic cleavage of the carbon−oxygen bond of the sulfenate. The two transient radicals formed then recombine to form the carbon−sulfur bond of the sulfoxide. The thermolysis of cinnamyl-4-nitrobenzenesulfenate has a positive entropy of activation (ΔS⧧ = 6.4 ± 2.0 eu in toluene), characteristic of a dissociative pathway. A normalsecondarykineticisotopeeffect (kH/kD =
Rhodium-Catalyzed Synthesis of α,β-Unsaturated Ketones through Sequential C–C Coupling and Redox Isomerization
作者:Hong-Shuang Li、Guili Guo、Rui-Ze Zhang、Fei Li
DOI:10.1021/acs.orglett.8b02190
日期:2018.8.17
A novel Rh(I)-catalyzed sequential C–C coupling and redox isomerization between allylicalcohols and 1,3-dienes has been accomplished. This versatile protocol provides expeditious access to a broad range of polysubstituted α,β-unsaturatedketones with excellent atom economy and regioselectivity.
A potassium‐bis(trimethylsilyl)amide‐mediated cyclopropanation of allylphosphates with silylboronates has been developed. Unlike the reported copper‐catalyzed allylic substitution reactions, the nucleophile selectively attacks at the β‐position of the allylic substrates under the present reaction conditions. The mechanism of this process has also been investigated, thus indicating the involvement
Iridium‐Catalyzed Enantioselective Hydroarylation of Alkenes through C−H bond Activation: Experiment and Computation
作者:Valmik S. Shinde、Manoj V. Mane、Luigi Cavallo、Magnus Rueping
DOI:10.1002/chem.202001793
日期:2020.7.2
A new catalytic enantioselective hydroarylation of unactivated olefins is developed that provides rapid access to functionalized chiral dihydrobenzofurans with good yields and excellent enantioselectivities. Simple aromatic ketones or amides act as a directing group allowing the regioselective reaction at the more hindered ortho position. Tertiary benzylic stereocenters are obtained directly under