ChemInform Abstract: Chemical and Electrochemical Asymmetric Dihydroxylation of Olefins in I2‐K2CO3‐K2OsO2(OH)4 and I2‐K3PO4/K2HPO4‐K2OsO2(OH)4 Systems with Sharpless Ligand.

Abstract

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Electrophotocatalytic Acetoxyhydroxylation of Aryl Olefins

“…Thus, there has been a thrust to develop alternative methods that utilize non-transition metal reagents or catalysts. − Still, these methods often rely on stoichiometric oxidizing agents that themselves have safety or cost concerns, particularly when large-scale reactions are involved. In this regard, electrochemistry − could offer an attractive alternative − by obviating the need for an external oxidant (Figure B). Toward this goal, Torii reported a dihydroxylation that utilized an electrochemical potential for catalyst regeneration, , although the method still relied on osmium catalysis.…”

Recent Applications of Homogeneous Catalysis in Electrochemical Organic Synthesis

“…However, because of the cost of Os catalysts, direct interaction of chiral Os catalysts with anodes requires increased catalyst loading, and is an expensive process. When inexpensive ferricyanide (Figure 35a) 142 or I 2 (Figure 35b) 143 is used as a mediator, the Os catalyst operates without the direct interaction with anode. So, homogeneous asymmetric dihydroxylation of alkenes 35-1 and 35-4 with catalysis by a chiral alkaloid-Os complex produces 1,2-dihydroxy products 35-2 and 35-5, respectively, in excellent yields with excellent enantioselectivities.…”

TEMPO-Enabled Electrochemical Enantioselective Oxidative Coupling of Secondary Acyclic Amines with Ketones

“…In alignment with our continuing efforts in organic electrochemistry, , we envision that a mediated electrochemical strategy for enantioselective oxidative coupling of secondary amines by merging amino catalysts and a redox mediator under electrochemical conditions would break this restriction. A redox mediator could decrease the oxidation potential of the reaction and accelerate the electron transfer at the electrode/electrolyte interface, which allows compounds with lower potentials to be preferentially oxidized. , The addition of mediators was proved to be effective for highly enantioselective electrochemical synthesis, which has encouraged chemists to develop new mediators and the corresponding catalytic systems . Furthermore, the characteristics of electrochemical cathode hydrogen evolution ,, can be used to remove excess protons in the system, avoiding their interference with reaction the intermediate.…”