Christopher R. K. Glasson

A new FeII quaterpyridyl M4L6 tetrahedron exhibiting selective anion binding

A rigid linear bis-bidentate quaterpyridine undergoes metal directed self-assembly with iron(ii) salts yielding M(4)L(6) host-guest complexes; selective anion binding for PF(6)(-) over BF(4)(-) is observed.

Unprecedented encapsulation of a [FeIIICl4]− anion in a cationic [FeII4L6]8+ tetrahedral cage derived from 5,5′′′-dimethyl-2,2′:5′,5′′:2′′,2′′′-quaterpyridine

A unique example of incorporation of a tetrahalometalate anion in a small supramolecular cage is described in which a tetrahedral cage of type [Fe4L6]8+ selectively encapsulates a [FeIIICl4]− anion over a [FeIICl4]2− anion in its central cavity to yield a discrete, mixed oxidation state, Fe(II)/Fe(III) supramolecular assembly. This unusual outcome has been achieved using two alternative synthetic strategies.

Interfacial Dynamics and Solar Fuel Formation in Dye-Sensitized Photoelectrosynthesis Cells

Dye-sensitized photoelectrosynthesis cells (DSPECs) represent a promising approach to solar fuels with solar-energy storage in chemical bonds. The targets are water splitting and carbon dioxide reduction by water to CO, other oxygenates, or hydrocarbons. DSPECs are based on dye-sensitized solar cells (DSSCs) but with photoexcitation driving physically separated solar fuel half reactions. A systematic basis for DSPECs is available based on a modular approach with light absorption/excited-state electron injection, and catalyst activation assembled in integrated structures. Progress has been made on catalysts for water oxidation and CO(2) reduction, dynamics of electron injection, back electron transfer, and photostability under conditions appropriate for water splitting. With added reductive scavengers, as surrogates for water oxidation, DSPECs have been investigated for hydrogen generation based on transient absorption and photocurrent measurements. Detailed insights are emerging which define kinetic and thermodynamic requirements for the individual processes underlying DSPEC performance.

Metal Template Synthesis of a Tripodal Tris(bipyridyl) Receptor that Encapsulates a Proton and an Iron(ii) Centre in a Pseudo Cage

The Fe(ii) template synthesis of the first member of a new category of tripodal tris-bipyridine ligands incorporating a nitrogen bridgehead is reported. The X-ray structure of the reaction product shows that the ligand adopts a pseudo cage-like structure that encapsulates both a proton and an Fe(ii) ion in its cavity. The complex shows an extended helical arrangement that is effectively ‘capped’ at its open end by a hydrogen bonded PF6– counter ion that is symmetrically aligned with the 3-fold axis of the helix. A 1H NMR study demonstrated that the encapsulated proton can be reversibly exchanged under acid/base conditions in CD3CN.

Modulating electron injection from an organic dye to a titania nanoparticle with a photochromic energy transfer acceptor

We have prepared titania nanoparticles with an organic dye sensitiser and diarylethene molecular switch attached to the surface. Spectroscopic investigations show that the dye sensitisers electron injection efficiency is reduced when the diarylethene is switched from its colourless, ring-open isomer to its coloured, ring-closed isomer, due to the introduction of a competing energy transfer pathway.

5,5′-Bis[(trimethyl­silyl)meth­yl]-2,2′-bipyridine

The molecule of the title compound, C18H28N2Si2, occupies a special position on an inversion centre. The Si—CH2—C(ipso) plane is approximately orthogonal to the plane of the pyridine rings, the corresponding dihedral angle being 82.0 (2)°.