Iodine-Promoted Metal-Free Aromatization: Synthesis of Biaryls, Oligo<i>p</i>-Phenylenes and A-Ring Modified Steroids
作者:Victoriano Domingo、Consuelo Prieto、Alexis Castillo、Lucia Silva、José F. Quílez del Moral、Alejandro F. Barrero
DOI:10.1002/adsc.201500303
日期:2015.10.12
efficient procedures based on the use of iodine for the synthesis of biaryls from arylcyclohexenols or arylcyclohexanols using sub-stoichiometric/catalytic iodine and dimethyl sulfoxide (DMSO) as oxidant. Heteroarylcyclohexanols also produced the corresponding biaryl products. It was proven that biphenyl can also be efficiently obtained when the quantity of iodine was reduced to 0.05 equiv. The method
Copper/Selectfluor-System-Catalyzed Dehydration-Oxidation of Tertiary Cycloalcohols: Access to β-Substituted Cyclohex-2-enones, 4-Arylcoumarins, and Biaryls
作者:Shaobo Ren、Jian Zhang、Jiahui Zhang、Heng Wang、Wei Zhang、Yunkui Liu、Miaochang Liu
DOI:10.1002/ejoc.201500610
日期:2015.8
A route to β-substitutedcyclohex-2-enones, 4-arylcoumarins, and biaryls has been developed. This approach involves a one-pot Cu0/Selectfluor-catalyzed dehydration–oxidation of tertiary cycloalcohols. Thus, by using 2 equiv. of Selectfluor at 25 °C, the dehydration–oxidation of tertiary cyclohexanols and oxabenzocyclohexanols gave β-substitutedcyclohex-2-enones and 4-arylcoumarins, respectively; whereas
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 Neutral FeCl3 Photocatalysis for C–C Bond Animation and Alkylation of Cyclic Alcohols
作者:Zongnan Zhang、Ting Xue、Rong Zeng、Zhe Han
DOI:10.1055/a-1966-3271
日期:2023.2
A modified method for iron-catalyzed C–C bond cleavage and amination and alkylation of nonactivated cyclic alcohols has been developed. Using FeCl3 as catalyst, the photoinduced ligand-to-metal charge transfer facilitates the generation of O-radicals from alcohols, the subsequent β-scission, and finally the radical trapping. Compared with the Fe(OR)3 catalysis, this mildly base-free system could enable