24395-10-6Relevant articles and documents
HOMOLYTIC DISPLACEMENT AT CARBON. XI. INTRAMOLECULAR HOMOLYTIC DISPLACEMENT AS A ROUTE TO CYCLOPENTANE AND TETRAHYDROFURAN DERIVATIVES FROM HEX-5-ENYL- AND HEX-3-OXO-5-ENYLCOBALOXIMES
Bongars, Christophe,Bougeard, Peter,Bury, Adrian,Cooksey, Christopher J.,Johnson, Michael D.,et al.
, p. 163 - 172 (1985)
5-Methylhex-5-enylcobaloxime reacts with carbon tetrachloride and with fluorotrichloromethane at 80-100 deg C to give substantially pure 1-methyl-1-(Β,Β,Β-trichloroethyl)- and 1-methyl-1-(β-fluoro-β,β-dichloroethyl)-cyclopentane.Hex-5-enylcobaloxime also gives trichloroethylcyclopentane from carbon tetrachloride, but the yield is dependent on the concentration of carbon tetrachloride.Similar cyclisation to give trichloroethyl- or fluorodichloroethyltetrahydrofuran is observed in the reactions of hex-3-oxo-5-enylcobaloxime with carbon tetrachloride and fluorotrichloromethane.However, no cyclisation was observed in the reactions of the ester, hex-2-one-3-oxo-5-enylcobaloxime, with carbon tetrachloride.These reactions are believed to take place by attack of a polyhalogenomethyl radical at the terminal unsaturated carbon of the organic ligand, followed either by an intramolecular homolytic displacement in which the carbon radical at position-5 attacks carbon-1 with displacement of cobaloxime(II), or by a halogen atom abstraction.
Fe-Catalyzed Anaerobic Mukaiyama-Type Hydration of Alkenes using Nitroarenes
Bhunia, Anup,Bergander, Klaus,Daniliuc, Constantin Gabriel,Studer, Armido
supporting information, p. 8313 - 8320 (2021/03/08)
Hydration of alkenes using first row transition metals (Fe, Co, Mn) under oxygen atmosphere (Mukaiyama-type hydration) is highly practical for alkene functionalization in complex synthesis. Different hydration protocols have been developed, however, control of the stereoselectivity remains a challenge. Herein, highly diastereoselective Fe-catalyzed anaerobic Markovnikov-selective hydration of alkenes using nitroarenes as oxygenation reagents is reported. The nitro moiety is not well explored in radical chemistry and nitroarenes are known to suppress free radical processes. Our findings show the potential of cheap nitroarenes as oxygen donors in radical transformations. Secondary and tertiary alcohols were prepared with excellent Markovnikov-selectivity. The method features large functional group tolerance and is also applicable for late-stage chemical functionalization. The anaerobic protocol outperforms existing hydration methodology in terms of reaction efficiency and selectivity.
Continuous Pd-Catalyzed Carbonylative Cyclization Using Iron Pentacarbonyl as a CO Source
Lopatka, Pavol,Markovi?, Martin,Koó?, Peter,Ley, Steven V.,Gracza, Tibor
, p. 14394 - 14406 (2019/11/11)
This work discloses a continuous flow carbonylation reaction using iron pentacarbonyl as source of CO. The described transformation using this surrogate was designed for use in commonly accessible flow equipment. Optimized conditions were applied to a sca