Synthesis of new poly(propylenimine) dendrimers DAB-dendr-[NH(O)COCH2CH2OC(O)C5H4Rh(NBD)]n {n = 4, 8, 16, 32, 64} functionalized with alkoxycarbonylcyclopentadienyl complexes of rhodium(i)

Abstract

The reaction between [Rh{C₅H₄CO₂(CH)₂OH}(NBD)] (1) and 1,1′-carbonyldiimidazole (CDI) leads to the new CO₂–imidazole functionalized alkoxycarbonylcyclopentadienyl complex [Rh{C₅H₄CO₂(CH₂)₂O₂C–Im}(NBD)] (2) (Im = imidazole). The latter was treated with five generations of poly(propylenimine) dendrimers DAB-dendr-(NH₂)_n {n = 4, 8, 16, 32, 64} (DAB = diaminobutane) to accomplish the synthesis of the new organometallic dendritic macromolecules DAB-dendr-[NH(O)COCH₂CH₂OC(O)C₅H₄Rh(NBD)]_n {n = 4 (4), 8 (5), 16 (6), 32 (7), 64 (8)} based on flexible poly(propylenimine) dendrimer cores, built up to the fifth generation. Spectroscopic characterization of all the new compounds will be presented and discussed.