Abstract
Photochromic pyrans for applications in material and life sciences were synthesized via palladium-mediated cyanation, carbonylation and Sonogashira cross-coupling starting from bromo-substituted naphthopyran
1
and benzopyrans
2a/b
. A novel photoswitchable benzopyran-based ω-amino acid
6
for Fmoc-based solid-phase peptide synthesis is presented. The photochromic behaviour of the 3-cyano-substituted benzopyran
5a
was investigated by time-resolved absorption spectroscopy in the picosecond time domain.