Rationally Designed Manganese-Based Metal-Organic Frameworks as Altruistic Metal Oxide Precursors for Noble Metal-Free Oxygen Reduction Reaction.

The sluggish oxygen reduction reaction (ORR) at the cathode is challenging and hinders the growth of hydrogen fuel cells. Concerning kinetic values, platinum is the best known catalyst for ORR; however, its less abundance, high cost, and corrosive nature warrant the development of low-cost catalysts. We report the hydrothermal synthesis of two novel Mn-based metal-organic frameworks (MOFs), [Mn(DOT)(HO)] () and [Mn(DOT)(BPY)(THF)] () (DOT = 2,5-dihydroxyterephthalate; BPY = 4,4'-bipyridine).

Fluorescence signaling systems for sensing Hg(II) ion derived from A2B-corroles.

Selective detection of Hg(II) ions in solution by a series of novel free base bis-(nitrophenyl) corroles (1-4) with general formula A(2)B (where A = nitrophenyl, and B = N,N-dimethylaminophenyl, thienyl, naphthyl and tridecyloxyphenyl group) is described. Among the free base corroles, 4, with a tridecyloxy long chain moiety, has been found to exhibit the highest Hg(II) sensing ability. The detection is based on the fluorescence quenching of the corroles, arising from the combined effect of static (coordination) and dynamic (exciplex formation) factors.

1-Phenyl-3-{4-[4-(4-undecyl-oxybenzoyl-oxy)phenyl-oxycarbon-yl]phen-yl}triazene 1-oxide.

The X-ray crystallographic study of the title compound, C(37)H(41)N(3)O(6), at 150 K establishes the N-oxide form of the triazene 1-oxide unit. There is one intra-molecular N-H⋯O hydrogen-bonding inter-action and the crystal packing is stabilized by one N-H⋯O, three C-H⋯O and three C-H⋯π inter-molecular inter-actions. The dihedral angles between pairs of adjacent benzene rings are 14.