Nickel-catalyzed coupling of benzyl acrylates with activated ketones and imines provides γ-butyrolactones and lactams, respectively. The benzyl alcohol byproduct released during the lactonization/lactamization event is relayed to the next cycle where it serves as the reductant for C-C bond formation. This strategy represents a conceptually unique approach to transfer-hydrogenative C-C bond form...

The first enantioselective Ni-catalyzed reductive acyl cross-coupling has been developed. Treatment of acid chlorides and racemic secondary benzyl chlorides with a Ni(II)/bis(oxazoline) catalyst in the presence of Mn(0) as a stoichiometric reductant generates acyclic α,α-disubstituted ketones in good yields and high enantioselectivity without requiring stoichiometric chiral auxiliaries or prege...

The use of NADH- and NADPH-dependent ketoreductases to access enantioenriched pharmaceutical building blocks is reported. Seven structurally diverse synthons are obtained, including those for atomoxetine (KRED 132), talampanel (RS1-ADH and CPADH), Dolastatin (KRED 132), and fluoxetine (KRED 108/132). Ethanol may be used as stoichiometric reductant, regenerating both nicotinamide cofactors, part...

An electrochemically driven, nickel-catalyzed reductive coupling of N-hydroxyphthalimide esters with aryl halides is reported. The reaction proceeds under mild conditions in a divided electrochemical cell and employs a tertiary amine as the reductant. This decarboxylative C(sp3)-C(sp2) bond-forming transformation exhibits excellent substrate generality and functional group compatibility. An ope...

Here, the evolution of titanocene-catalyzed hydrosilylation epoxides that yields corresponding anti-Markovnikov alcohols is summarized. The study focuses on aspects sustainability, efficient catalyst activation, and stereoselectivity. latest variant reaction employs polymethylhydrosiloxane (PMHS), a waste product Müller–Rochow process as terminal reductant, features an activation with benzylMgB...

Azotobacter vinelandii flavodoxin hydroquinone (FldHQ) is a physiological reductant to nitrogenase supporting catalysis that is twice as energy efficient (ATP/2e- = 2) as dithionite (ATP/2e- = 4). This catalytic efficiency results from reduction of Fe protein from A. vinelandii (Av2) to the all-ferrous oxidation state ([Fe4S4]0), in contrast to dithionite, which only reduces Av2 to the [Fe4S4]1...

The evolution of O(2)-producing cyanobacteria that use water as terminal reductant transformed Earth's atmosphere to one suitable for the evolution of aerobic metabolism and complex life. The innovation of water oxidation freed photosynthesis to invade new environments and visibly changed the face of the Earth. We offer a new hypothesis for how this process evolved, which identifies two critica...

by MUSHTAQUE AHMAD, M.S. Washington State University December 2008 Chair: Richard J. Watts Oxidant interaction with subsurface materials is a major factor influencing the effective application of in situ chemical oxidation (ISCO) for contaminant destruction. The newest and least explored ISCO oxidant source is persulfate. Persulfate interaction with subsurface minerals was investigated as a bas...

The objective of this study was to identify factors which limit leaf nitrate reductase (NR) activity as decline occurs during flowering and beginning seed development in soybean (Glycine max [L.] Merr. cv Clark). Level of NR enzyme activity, level of reductant, and availability of NO(3) (-) as substrate were evaluated for field-grown soybean from flowering through leaf senescence. Timing of rep...