72693-12-0Relevant articles and documents
Terminal-Selective Functionalization of Alkyl Chains by Regioconvergent Cross-Coupling
Dupuy, Stéphanie,Zhang, Ke-Feng,Goutierre, Anne-Sophie,Baudoin, Olivier
supporting information, p. 14793 - 14797 (2016/11/23)
Hydrocarbons are still the most important precursors of functionalized organic molecules, which has stirred interest in the discovery of new C?H bond functionalization methods. We describe herein a new step-economical approach that enables C?C bonds to be constructed at the terminal position of linear alkanes. First, we show that secondary alkyl bromides can undergo in situ conversion into alkyl zinc bromides and regioconvergent Negishi coupling with aryl or alkenyl triflates. The use of a suitable phosphine ligand favoring Pd migration enabled the selective formation of the linear cross-coupling product. Subsequently, mixtures of secondary alkyl bromides were prepared from linear alkanes by standard bromination, and regioconvergent cross-coupling then provided access to the corresponding linear arylation product in only two steps.
Efficient and selective oxidation of methyl substituted cycloalkanes by heterogeneous methyltrioxorhenium-hydrogen peroxide systems
Bianchini, Gianluca,Crucianelli, Marcello,Canevali, Carmen,Crestini, Claudia,Morazzoni, Franca,Saladino, Raffaele
, p. 12326 - 12333 (2007/10/03)
Polymer-supported methyltrioxorhenium (MTO) systems are efficient catalysts for the oxidative functionalisation of cyclohexane and cyclopentane derivatives with H2O2 as oxygen donor. Using poly(4-vinyl)pyridine and poly(4-vinyl)pyridine-N-oxide as MTO supports, cycloalkanol, cycloalkanediol, cycloalkanone and ω-hydroxy methyl ketone derivatives were obtained in different yields depending on the experimental conditions. Interestingly, cycloalkane dimers were selectively recovered in acceptable to good yields when the oxidation was performed with polystyrene-microencapsulated MTO catalyst. The EPR investigation suggests that the homolytic cleavage of the CH3-Re bond with formation of CH3{radical dot} radicals occurs inside the polystyrene capsule, indicating a possible role of methyl radical in the cycloalkane dimerisation pathway.
Functionalization of non-activated C-H bonds in ketones and imines with HF/SbF5/CCl4
Thibaudeau, Sébastien,Martin-Mingot, Agnès,Jouannetaud, Marie-Paule,Jacquesy
, p. 6643 - 6649 (2007/10/03)
Reaction of cyclic ketones 2-6 and imines 15-17 in HF/SbF5 in presence of CCl4 yield hydroxy or fluoroderivatives, hydride abstraction occurring at a site located far from the functional group. Whereas ketones 2-5 yield only hydroxy derivatives, through cyclic carboxonium ion, imines 15, 16 N-protonated in the media conditions give only fluoroderivatives 18, 19, respectively, after quenching with HF-pyridine. Ring contraction is operative when starting from large membered ring ketones 24 and 25, and imine 26, leading to a mixture of hydroxy or fluoro cyclohexanones and/or cycloheptanones.
Fluorination or hydroxylation of non activated C-H bonds in amides and ketones using CCl4 or NBS in superacids
Martin, Agnes,Jouannetaud, Marie-Paule,Jacquesy, Jean-Claude
, p. 2967 - 2970 (2007/10/03)
Amides and ketones are fluorinated or hydroxylated in HF-SbF5 in the presence of CCl4 or NBS, reaction occurring at a carbon far located from the functional group.