Construction and Strong Feller Property of Distorted Elliptic Diffusion with Reflecting Boundary

Using Dirichlet form techniques we prove existence of a diffusion process with singular drift on an open domain Ω???? ^d , d?∈??, d?≥?2, and generalized reflection at the boundary. The boundary is assumed to be C ²-smooth except for a sufficiently small set. We prove an elliptic regularity result which gives L ^p -strong Feller property for the semigroup and resolvent for p?≥?2 with $p > \frac{d}{2}$ . This result allows us to construct the process pointwisely except for an explicitly known set. For starting points outside this known set the process solves the corresponding martingale problem. The results are applied to prove the existence of the stochastic dynamics of a finite interacting particle system and for the Ginzburg-Landau interface model with a hard wall.     

Easily assembled,modular N,O-chelating ligands for Ta(V) complexation: a comparative study of ligand effects in hydroaminoalkylation with N-methylaniline and 4-methoxy-N-methylaniline

The influence of structurally related N,O-chelating ligands with additional heteroatoms (N, O, P, S) on the reactivity of in situ generated tantalum complexes for the hydroaminoalkylation of amines has been explored. Reactivity was probed by evaluating the catalytic ability of these N,O-chelating systems with N-methylaniline and 4-methoxy-N-methylaniline substrates. Enhanced reactivity is observed with amide proligands bearing an ortho-methoxyphenyl group on the nitrogen. 4-Methoxy-N-methylaniline is found to be more prone to undergo C–H functionalization via hydroaminoalkylation than N-methylaniline. The use of the related substrate 2-methoxy-N-methylaniline is not tolerated, and instead C(sp³)–O bond cleavage was observed.     

A Self‐Assembled Luminescent Host That Selectively Senses ATP in Water

Metal‐ion‐directed self‐assembly has been used to construct kinetically inert, water‐soluble heterometallic Ru₂Re₂ hosts that are potential sensors for bioanions. A previously reported metallomacrocycle and a new derivative synthesised by this approach are found to be general sensors for bioanions in water, showing an “off–on” luminescent change that is selective for nucleotides over uncharged nucleobases. Through a change in the ancillary ligands coordinated to the ruthenium centres of the host, an “off–on” sensor has been produced. Whilst this host only shows a modest enhancement in binding affinities for nucleotides relative to the other two host systems, its sensing response is much more specific. Although a distinctive “off–on” luminescence response is observed for the addition of adenosine triphosphosphate (ATP), related structures such as adenine and guanosine triphosphate (GTP) do not induce any emission change in the host. Detailed and demanding DFT studies on the ATP‐ and GTP‐bound host–guest complexes reveal subtle differences in their geometries that modulate the stacking interactions between the nucleotide guests and the ancillary ligands of the host. It is suggested that this change in stacking geometries affects solvent accessibility to the binding pocket of the host and thus leads to observed difference in the host luminescence response to the guests.     

Potassium hydrogen diphthalate dihydrate: a new structure and correction to the literature

The title compound, K⁺·[(C₈H₅O₄)₂H]⁻·2H₂O or K⁺·C₁₆H₁₁O₈⁻·2H₂O, was prepared by slow evaporation of an aqueous solution of potassium hydrogen phthalate. The molecular complex consists of a potassium cation coordinated to a proton‐bound hydrogen phthalate dimer and two water mol­ecules. The potassium cation resides on a twofold axis in a distorted square‐antiprism coordination geometry. The compound is isomorphous with the ammonium analogue, previously misidentified. As potassium hydrogen phthalate is frequently used in the manufacture of buffers, organic carbon standards, acidimetric standards and various other products, the crystallization of a compound with a different stoichiom­etery from a solution containing the acidimetric standard has important practical implications.