Photolysis of 1-Alkylcycloalkanols in the Presence of (Diacetoxyiodo)benzene and I<sub>2</sub>. Intramolecular Selectivity in the β-Scission Reactions of the Intermediate 1-Alkylcycloalkoxyl Radicals
作者:Carla S. Aureliano Antunes、Massimo Bietti、Osvaldo Lanzalunga、Michela Salamone
DOI:10.1021/jo049524y
日期:2004.8.1
and 1-phenylcyclooctoxyl radicals, formation of products deriving from an intramolecular 1,5-hydrogen atom abstraction reaction from the cycloalkane ring has also been observed. The results are discussed in terms of release of ring strain associated to ring opening, stability of the alkyl radical formed by C-alkyl cleavage, and with cycloheptoxyl and cyclooctoxyl radicals, also in terms of the possibility
Ring-opening iodination and bromination of unstrained cycloalkanols through β-scission of alkoxy radicals
作者:Jiang-Ling Shi、Yuankai Wang、Zixuan Wang、Bowen Dou、Jianbo Wang
DOI:10.1039/d0cc01720e
日期:——
Ring-opening iodination or bromination of unstrained cycloalkanols with NaI or NaBr and PhI(OAc)2 under visible light irradiation is developed. In this protocol the concentration of I2 is modulated through the generation of triiodide (I3-), thus significantly avoiding undesired side reactions. The reaction is under mild conditions and has a wide substrate scope, thus providing a practically useful
An efficient copper-catalyzed radical ring-opening halogenation with HX (aq) is described. This protocol features redox-neutral conditions, green halogen sources, and a broad substrate scope, providing practical access to distally chlorinated, brominated and iodinated alkyl ketones and alkyl nitriles with moderate to good yields.
Visible-Light-Enhanced Ring Opening of Cycloalkanols Enabled by Brønsted Base-Tethered Acyloxy Radical Induced Hydrogen Atom Transfer-Electron Transfer
作者:Rong Zhao、Yuan Yao、Dan Zhu、Denghu Chang、Yang Liu、Lei Shi
DOI:10.1021/acs.orglett.8b00161
日期:2018.2.16
A metal-free ringopening/halogenation of cycloalkanols, which combines both PPO/TBAX oxidant system and blue LEDs irradiation, is presented. This method produces diverse γ, δ, and even more remotely halogenated ketones in moderate to excellent yields under mild conditions. Interestingly, experimental and computational studies demonstrate the novel ring size-dependent concerted/stepwise (four-/five-
A new approach for the copper-catalyzed functionalization of alkyl hydroperoxides with organosilicon compounds via in-situ-generated alkylsilyl peroxides
Using organosilicon compounds of the type Me3SiX (X = CN, N3, CnF2n+1, and halogens) and an amine base, alkylsilyl peroxides were generated in situ from the corresponding alkyl hydroperoxides. Subsequent in situ copper-catalyzed homolytic cleavage of the alkylsilyl peroxides afforded alkyl radicals, which were then trapped with a nucleophile X (X = CN, N3, CnF2n+1, and halogens) to furnish coupling
使用 Me 3 SiX 类型的有机硅化合物(X = CN、N 3、C n F 2n+1和卤素)和胺碱,由相应的烷基氢过氧化物原位生成烷基甲硅烷基过氧化物。随后的原位铜催化均裂烷基过氧化硅得到烷基自由基,然后被亲核试剂 X (X = CN, N 3 , C n F 2n+1, 和卤素) 以提供具有新碳-碳、碳-氮或碳-卤素键的偶联产物,产率从好到高。此外,1-(三甲基甲硅烷基)吗啉还可用于原位生成过氧化烷基甲硅烷基,随后高效地用于酰胺的N-烷基化、芳基化和硼基化。