Preparation and characterization of a new derivative of rhodamine B with an alkoxysilane moiety

The synthesis of a novel rhodamine B derivative carrying an alkoxysilane moiety (RBS) is described. Rhodamine B (RB) was attached to the Si atom by an amide linkage to provide the functionalized silane via the condensation of 3-aminopropyltriethoxysilane (APTES) with RB by azeotropic distillation in water. The physical properties and structure of RBS were characterized using 1H NMR, 13C NMR, HH COSY, FTIR, UV–vis measurements spectra and Kofler's apparatus. The absorbance of RBS was 1.6 times higher than that of RB. The equilibrium conformation of the RBS molecule was determined by means of a molecular simulation study; spectral properties are discussed based on the obtained computational results.