Premium
Cyclohexyl Bromide and Iodide: Direct Reduction at Vitreous Carbon Cathodes together with Nickel(I) Salen‐ and Cobalt(I) Salen‐Catalyzed Reductions in Dimethylformamide
Author(s) -
Gerroll Benjamin H. R.,
Bird Sean P.,
Martin Erin T.,
Mubarak Mohammad S.,
Peters Dennis G.
Publication year - 2018
Publication title -
chemelectrochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.182
H-Index - 59
ISSN - 2196-0216
DOI - 10.1002/celc.201700664
Subject(s) - carbanion , chemistry , cyclic voltammetry , cobalt , inorganic chemistry , catalysis , bromide , nickel , dimethylformamide , iodide , glassy carbon , electrolysis , cyclohexane , electrochemistry , organic chemistry , electrode , solvent , electrolyte
Cyclic voltammetry and controlled‐potential (bulk) electrolysis have been used to study the direct electrochemical reduction of cyclohexyl bromide ( 1 ) and cyclohexyl iodide ( 2 ) at glassy carbon cathodes in dimethylformamide (DMF) containing 0.10 M tetramethylammonium tetrafluoroborate (TMABF 4 ). Direct reduction of 1 is a one‐step process that affords a carbanion intermediate, whereas 2 undergoes stepwise reduction to a radical and then a carbanion intermediate. Mixtures of cyclohexane, cyclohexene, and bicyclohexyl arise from bulk electrolyses of both 1 and 2 . Catalytic reduction of 1 and 2 by nickel(I) salen and cobalt(I) salen electrogenerated at glassy carbon cathodes in DMF‐TMABF 4 has been investigated with the aid of both cyclic voltammetry and bulk electrolysis. Products arising from these catalytic reductions are cyclohexane, cyclohexene, and bicyclohexyl, although significant amounts of unreduced 1 are found when cobalt(I) salen is utilized as the catalyst. Mechanistic aspects of the direct and catalyzed reductions of 1 and 2 are discussed.