The new bis(bidentate) tetraphosphane ,,-1,2,3,4-tetrakis(diphenylphosphanyl)buta-1,3-diene (dppbd) () was obtained by applying a photochemical synthetic protocol. The key step of the photochemical reaction consisted of an intramolecular [2+2] cycloaddition involving a C-C double and triple bond of the Pt-dimer species of the formula [PtCl(dppa)(-dppen)] () {dppa = 1,2-bis(diphenylphosphanyl)acetylene and dppen = 1,2-bis(diphenylphosphanyl)ethene} leading to [PtCl(dppbd)] (). The asymmetrically bridged precursor complex was obtained by combinatorial chemistry.
View Article and Find Full Text PDFInspired by natural photosynthesis, features such as proton relays have been integrated into water reduction catalysts (WRC) for effective production of hydrogen. Research by DuBois et al. showed the crucial influence of these relays, largely in the form of pendant amine functions.
View Article and Find Full Text PDFMost of the systems for photochemical hydrogen production are not stable and suffer from decomposition. With bis(bidentate) tetraphosphane ligands the stability increases enormously, up to more than 1000 h. This stability was achieved with a system containing osmium(ii) as a light harvesting antenna and palladium(ii) as a water reduction catalyst connected with a bis(bidentate) phosphane ligand in one molecule with the chemical formula [Os(bpy)(dppcb)Pd(dppm)](PF).
View Article and Find Full Text PDFRupture of the anterior cruciate ligament (ACL) is a high incidence injury usually treated surgically. According to common knowledge, it does not heal spontaneously, although some claim the opposite. Regeneration therapy by Khalifa was developed for injuries of the musculoskeletal system by using specific pressure to the skin.
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