A novel protocol for the efficient activation of the Beckmannrearrangement utilizing the readily available sulfuryl fluoride (SO2F2 gas) is reported. The substrate scope of this methodology has been demonstrated by 37 examples with good to nearly quantitative isolated yields in a short time. A tentative mechanism was proposed involving formation and elimination of sulfonyl ester.
报道了一种利用容易获得的硫酰氟(SO 2 F 2气体)有效激活贝克曼重排的新方案。该方法的底物范围已通过37个实例证明,并在短时间内获得了良好至近乎定量的分离产率。提出了一种尝试性的机制,涉及形成和消除磺酰基酯。
Copper-catalyzed synthesis of thiazol-2-yl ethers from oxime acetates and xanthates under redox-neutral conditions
acetates and xanthates for the synthesis of thiazol-2-yl ethers with remarkable regioselectivity has been developed. Various oxime acetates, whether derived from aryl ketones or alkyl ketones, or natural product cores are suitable for this conversion. Unique dihydrothiazoles were also obtained when both reaction sites were methine. Mechanistic studies indicated that imino copper(III) intermediates were involved
Quinone-sensitized Steady-state Photolysis of Acetophenone Oximes Under Aerobic Conditions: Kinetics and Product Studies†
作者:Adriana Park、Nicole M. Kosareff、Jason S. Kim、H. J. Peter de Lijser
DOI:10.1562/2005-04-23-ra-496
日期:——
(PET) results in the formation of the corresponding ketones as the major product via oxime radical cations and iminoxyl radicals. The influence of electron-releasing and electron-accepting substituents on these reactions was studied. The observed substituenteffect strongly supports formation of iminoxyl radicals from the oximes via an electron transfer-proton transfer sequence rather than direct hydrogen
Direct Enamido C(sp<sup>2</sup>)−H Diphosphorylation Enabled by a PCET‐Triggered Double Radical Relay: Access to<i>gem</i>‐Bisphosphonates
作者:Hao‐Qiang Cao、Hao‐Nan Liu、Zhe‐Yuan Liu、Bao‐Kun Qiao、Fa‐Guang Zhang、Jun‐An Ma
DOI:10.1002/chem.202000517
日期:2020.4.24
electron-transfer (PCET)-triggered enamidoC(sp2 )-Hdiphosphorylation. This reaction represents a rare example of realizing the challenging double C-P bond formation at a single carbon atom, thus providing facile access to a broad variety of structurally diverse bisphosphonates from simple enamides under silver-mediated conditions. Initial mechanistic studies demonstrated that the diphosphorylation involves
spectroscopy (XPS) analysis suggest that iron is crucial in the catalytic cycle, working to prohibit the deactivation of selenium catalyst through an iron‐catalyzed aerobic oxidation of lowvalent selenium species by air to the active high valent selenium species. Since air can be utilized as the terminal oxidant, this work may contribute to the advance of organoselenium catalysis.