Nicotinamide adenine dinucleotide (NAD + ) is one of the most important redox mediators in biological systems and acts as a reservoir/source of two electrons and a proton.[1] The NAD + /NADH redox couple has been drawing much attention because bioinspired chemical reactions that produce neither high-energy intermediates nor unwanted by-products promise to be key factors in realizing sustainable energy sources. Large numbers of photochemical reactions mediated by NADH model compounds, such as reduction of alkyl halides, olefins, and ketones and photoinduced electron transfer, as well as thermal reactions using NADH analogues, have been extensively studied.[ ; bpy = 2,2'-bipyridine, pbn = 2-(2-pyridyl)benzo[b]-1,5-naphthyridine), which acts as a catalyst in the electrochemical reduction of acetone to 2-propanol, similar to the enzymatic NAD + /NADH.[3] While the mechanism remains unclear, this is the first example indicating that an NADH model complex such as [Ru (bpy) (Figure 2). This finding indicates that the one-electron reduction is coupled with a proton-transfer reaction to form the neutral ligand radical [Ru(bpy) 2 (pbnHC)] 2+. TD-B3LYP/LANL2DZ calculations of [1] 2+ in both the gas phase and in a self-consistent-reaction-field, polarizable continuum model of acetonitrile yielded the spectra shown in Figure S1 in the Supporting Information. The two strong lines in the solution-phase spectrum at 510 and 429 nm correspond to HOMOÀ1 to LUMO and HOMOÀ2 to LUMO + 1 transitions, respectively (Figure 3 and Figure S2 in the Supporting Information). The positions and intensities of the gasphase transitions between 500 and 450 nm are significantly affected by solvation. The solution-phase spectrum is in better accord with the experimental spectrum shown in Figure 4. B3LYP/LANL2DZ calculations show that the HOMO is primarily a Ru d orbital and the LUMO is almost exclusively

This paper describes the synthesis of highly sterically hindered piperidinyl trisulfide with four spirocyclohexyl moieties, bis(2,6-bis[spirocyclohexyl]piperidine-1-yl)trisulfide (BIBSCPS-S3), from commercially available starting materials in short steps and its application as a...

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It is shown that industrially available 2,3-dichloro-1,3-butadiene is a useful starting material for the synthesis of 2,3-diaryl-1,3-butadienes. Ni(II)-catalyzed cross-coupling reaction of 2,3-dichloro-1,3-butadiene with ArMgBr (Ar = 2-thienyl, phenyl, 4-dodecyloxyphenyl, and 4-fluorophenyl) gives the corresponding 2,3-diaryl-1,3-butadienes in good yields.