End functional ROMP polymers via degradation of a ruthenium Fischer type carbene†
A new functional terminating agent leading to aldehyde end functional ROMP polymers is reported. The terminating agent acts via formation of a spontaneously degrading ruthenium Fischer type carbene, whose decomposition can be dramatically accelerated with a strong acid. The mechanism of degradation of the Fischer carbene has been elucidated with the help of monoisotopically resolved MALDI-ToF mass spectrometry of the resulting polymer. End functional polymers can therefore be exploited as versatile analytes giving information about the mechanism of small molecules acting on the polymer chain end. Further derivatization of the aldehyde end group was carried out using dopamine in a reductive amination step. A superparamagnetic iron oxide nanoparticle (SPION) binding polymer could thereby be prepared.