Surface wettability is an important physicochemical property of biomaterials, and it would be more helpful for understanding this property if a wide range of wettability are employed. This study focused on the effect of surface wettability on fibroblast adhesion over a wide range of wettability using a single material without changing surface topography. Plasma polymerization with hexa methyldisiloxane followed by oxygen (O 2 ) plasma treatment was employed to modify the surfaces. The water contact angle of sample surfaces varied from 106 degrees (hydrophobicity) to almost 0 degrees (super-hydrophilicity). O 2 -functional groups were introduced on polymer surfaces during O 2 -plasma treatment. The cell attachment study confirmed that the more hydrophilic the surface, the more fibroblasts adhered in the initial stage that includes on super-hydrophilic surfaces. Cells spread much more widely on the hydrophilic surfaces than on the hydrophobic surfaces. There was no significant difference in fibroblast proliferation, but cell spreading was much greater on the hydrophilic surfaces. These findings suggest the importance of the surface wettability of biomaterials on initial cell attachment and spreading. The degree of wettability should be taken into account when a new biomaterial is to be employed. Further research of surface wettability on adhesive molecules is necessary for a better understanding of this property.

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Treatment of a dinuclear Ru(II) amido complex [Cp*Ru(mu2-NHPh)]2 (Cp* = eta5-C5Me5) with small organic substrates including CO, tert-butyl isocyanide, a sulfur ylide Ph2S=CH2, and diphenylacetylene resulted in an unexpected disproportionation reaction of the bridging amido ligands to produce a free amine and a series of imido-bridged diruthenium complexes [(Cp*Ru)2(mu2-L)(mu2-NPh)] (L = CO, t-BuNC, CH2). In the case of diphenylacetylene, the bridging imido ligand underwent subsequent coupling reaction with the coordinated alkyne to form an iminoalkenyl complex [(Cp*Ru)2(mu2-PhNCPhCPh)].

Treatment of the thioethers (RNH-o-C 6 H 4 ) 2 S (H 2 [R 2 NSN]; R ) Xy, Xyf; Xy ) 3,5-Me 2 C 6 H 3 , Xyf ) 3,5-(CF 3 ) 2 C 6 H 3 ) with 2 equiv of n-BuLi followed by addition of 0.5 equiv of [(η 6 -C 6 H 6 )-RuCl 2 ] 2 in THF gave the bis(diarylamido)/thioether complexes [(η 6 -C 6 H 6 )Ru[R 2 NSN]] (R ) Xy (1a), R ) Xyf (1b)) in moderate yields. In the presence of 1a (1 mol %) and PCy 3 (2 mol %; Cy ) cyclohexyl), benzonitrile was catalytically hydrogenated to give benzylamine (72%) and benzylidenebenzylamine (27%) at 80 °C and 30 atm, while the hydrogenation with 1b as a catalyst precursor resulted in the formation of benzylamine (37%) and benzylidenebenzylamine (51%) under the same reaction conditions. The yield of benzylamine was improved up to 92% by using a catalyst mixture of 1a (1 mol %)/PCy 3 (2 mol %)/t-BuONa (10 mol %). On the other hand, the reaction of 1a with excess PMe 3 afforded the tris(trimethylphosphine) derivative [(PMe 3 ) 3 Ru[Xy 2 NSN]] (2). Treatment of 2 with excess PhCN, MeCN, or N 2 H 4 ‚ H 2 O resulted in the replacement of a PMe 3 ligand by these substrates to give [(PMe 3 ) 2 LRu-[Xy 2 NSN]] (3, L ) PhCN; 4, L ) MeCN; 5, L ) N 2 H 4 ), while the reaction of 2 with benzoylhydrazine gave the κ 2 -benzoylhydrazido complex [(PMe 3 ) 2 Ru(κ 2 -(O,N)-PhC(O)d NNH 2 )(H[Xy 2 NSN])] (6). Structures of 1a, 1b, 2, 5, and 6 have been determined by X-ray crystallography.