A simple approach to a new T-POSS based MRI contrast agent.

A fast and simple route was developed to synthesize a new T-silsesquioxane based contrast agent for potential application in Magnetic Resonance Imaging. For this purpose the novel C-thiol-functionalized T-silsesquioxane (3) was constructed as a carrier molecule as well as the DOTA based gadolinium(iii) complex (11) equipped with allyl terminated linkers was prepared. The linkage of the complexes to the T-silsesquioxane was performed via an UV-light catalyzed thiol-ene click reaction within one hour which affords the desired product 13 in a yield of 80%.