Design and synthesis of a photoswitchable guanidine catalyst

A novel design as well as a straight-forward synthesis for a photoswitchable guanidine catalyst is reported. Intense studies of the photochromic properties demonstrated the reversible switchability of its photosensitive azobenzene moiety. Its activity in the ring-opening polymerization (ROP) of rac-lactide was investigated as well. The obtained results are discussed, and an additional guanidine was synthesized and utilized in the ROP of rac-lactide in order to explain the findings.