Synthesis and characterization of dendrons and dendrimers skeleton-constructed with azobenzene moiety

摘要

A series of dendrons and dendrimers skeleton-constructed with azobenzene moiety based upon 4-carboxy-4-(1,2-propanediolether)-azobenzene as an AB(2) monomer, via a convergent approach, proceeding in a repeated stepwise growth manner starting from 4-carboxy-4-(n-butylether)-azobenzene as a peripheral monomer, were synthesized, and characterized by NMR, FTIR, and MALDI-TOF-MS analysis. Their regular molecular architecture and thus monodispersed molecular weights were confirmed by GPC. The UV-Vis absorbance and H-1 NMR spectrum study indicated that the azobenzene moieties in CHCl3 solution took fully trans-cis isomerization under UV irradiation, and reversely isomerization back to the trans by visible light irradiation or by heat. (c) 2007 Elsevier Ltd. All rights reserved.