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Water is the ideal green solvent for organic electrosynthesis. However, a majority of electroorganic processes require potentials that lie beyond the electrochemical window for water. In general, water oxidation and reduction lead to poor synthetic yields and selectivity or altogether prohibit carrying out a desired reaction. Herein, we report several electroorganic reactions in water using synthetic strategies referred to as reductive oxidation and oxidative reduction. Reductive oxidation involves the homogeneous reduction of peroxydisulfate (S2O82–) via electrogenerated Ru(NH3)62+ at potential of –0.2 V vs. Ag/AgCl (3.5 M KCl) to form the highly oxidizing sulfate radical anion (E0′ (SO4•–/SO42–) = 2.21 V vs. Ag/AgCl), which is capable of oxidizing species beyond the water oxidation potential. Electrochemically generated SO4•– then efficiently abstracts a hydrogen atom from a variety of organic compounds such as benzyl alcohol and toluene to yield product in water. The reverse analogue of reductive oxidation is oxidative reduction. In this case, the homogeneous oxidation of oxalate (C2O42–) by electrochemically generated Ru(bpy)33+ produces the strongly reducing carbon dioxide radical anion (E0′ (CO2•–/CO2) = –2.1 V vs. Ag/AgCl), which is capable of reducing species at potential beyond the water or proton reduction potential. In preliminary studies, the CO2•– has used to homogenously reduce the C–Br moiety belonging to benzyl bromide at an oxidizing potential in aqueous solution. 

Electrochemical dehalogenation of polyhalogenated compounds is an inefficient process as the working electrode is passivated by the deposition of short-chain polymers that form during the early stages of electrolysis. Herein, we report the use of 1, 1, 1, 3, 3, 3-hexaflouroisopropanol (HFIP) as an efficient reagent to control C–H formation over the radical association. Debromination of 1,6-dibromohexane was examined in the presence of Ni(II) salen and HFIP as the electrocatalyst and hydrogen atom source, respectively. Electrolysis of 10 mM 1,6-dibromohexane and 2 mM Ni(II) salen in the absence of HFIP yields 50% unreacted 1,6-dibromohexane and ∼40% unaccounted for starting material, whereas electrolysis with 50 mM HFIP affords 65%n-hexane. The mechanism of hydrogen atom incorporation was examined via deuterium incorporation coupled with high-resolution mass spectrometry, and density functional theory (DFT) calculations. Deuterium incorporation analysis revealed that the hydrogen atom originated from the secondary carbon of HFIP. DFT calculations showed that the deprotonation of hydroxyl moiety of HFIP, prior to the hydrogen atom transfer, is a key step for C–H formation. The scope of electrochemical dehalogenation was examined by electrolysis of 10 halogenated compounds. Our results indicate that through the use of HFIP, the formation of short-chain polymers is no longer observed, and monomer formation is the dominant product.