Rapid generation of HNO induced by visible light.

We present a new method for controlled generation of HNO, based on the combination of a pH photoactuator induced by visible light with an HNO donor activated by pH increase. This method avoids the use of UV light, and in the future could be extended by using an IR photoactuator.

Transient photocyclization in ruthenium(ii) polypyridine complexes of indolamines.

Ruthenium polypyridine complexes have proved to be useful caging groups for visible-light photodelivery of biomolecules. In most photoreactions, one ligand is expelled upon irradiation, yielding ruthenium mono-aqua complexes and no other photoproduct. In this work we show that a long-lived transient photoproduct is generated when the ruthenium complexes involve indolamines. The spatial conformation of this species is compatible with a cyclic structure that contains both the amine and the normally non-coordinating aromatic ring coordinated to the ruthenium center.