Novel photoswitching dithienylethenes with ferrocene units

Two novel dithienylethenes with ferrocene units were synthesized by Wittig reaction. The structure of 2a has been established by X-ray diffraction studies. They could reversibly interconvert between two thermally stable forms, an open and a closed one, using light of different wavelengths as triggers. Copyright (c) 2006 John Wiley & Sons, Ltd.