Towards Redox-Driven Unidirectional Molecular Motion.

Redox-driven molecular motion is an attractive alternative to light-driven processes. Here, the ability of an overcrowded alkene-based unimolecular light-driven rotary motor (A) to be driven by oxidation/reduction cycles is explored. We show that two-electron oxidation of A is followed by irreversible deprotonation and reduction to form a monocationic species D(+) , in which the stereogenic center is lost.

Electrochemistry of dithienylethenes and their application in electropolymer modified photo- and redox switchable surfaces.

Diarylethenes have proven to be versatile responsive components in many applications due to their photochromic properties. In recent years their potential use as redox switchable components has become increasingly apparent. Applying dithienylethenes as redox switchable components requires their immobilisation on conducting substrates and hence electropolymerisation is a promising, albeit, challenging approach to developing such systems.

Ligand exchange and spin state equilibria of Fe(II)(N4Py) and related complexes in aqueous media.

We report the characterization and solution chemistry of a series of Fe(II) complexes based on the pentadentate ligands N4Py (1,1-di(pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine), MeN4Py (1,1-di(pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)ethanamine), and the tetradentate ligand Bn-N3Py (N-benzyl-1,1-di(pyridin-2-yl)-N-(pyridin-2-ylmethyl)methanamine) ligands, i.e., [Fe(N4Py)(CH(3)CN)](ClO(4))(2) (1), [Fe(MeN4Py)(CH(3)CN)](ClO(4))(2) (2), and [Fe(Bn-N3Py)(CH(3)CN)(2)](ClO(4))(2) (3), respectively.

Multiple flow profiles for two-phase flow in single microfluidic channels through site-selective channel coating.

An approach to control two-phase flow systems in a poly(dimethylsiloxane) (PDMS) microfluidic device using spatially selective surface modification is demonstrated. Side-by-side flows of ethanol : water solutions containing different polymers are used to selectively modify both sides of a channel by laminar flow patterning. Introduction of air pockets during modification allows for control over the length of the channel section that is modified.

Symmetric six-fold arrays of photo- and electrochromic dithienylethene switches.

The direct synthesis of six-fold symmetric hexaphenylbenzenes with multiple photochromic dithienylethene units via a cobalt-catalyzed cyclotrimerization is reported. This approach allows for six photochromic units to be held in proximity with a well-defined spatial separation without affecting the photochromic properties of each unit.