Dendritic polyols of the second and third generation 2G-OH8 (1), 2G-OH16 (2), and 3G-OH16 (3) were prepared by hydroboration/oxidation of allyl-terminated carbosilane dendrimers and used as supports for the immobilization of cyclopentadienyltrichlorotitanium(IV) complexes via alcoholysis. The reaction of 1–3 with CpTiCl3 gave metallodendrimers 2G-(OTiCpCl2)8 (4a), 2G-(OTiCpCl2)16 (5a), and 3G-(OTiCpCl2)16 (6a), respectively, whereas the reaction of 1 and 3 with CpSiFTiCl3 (CpSiF = C5H4SiMe2CH2CH2C8F17) yielded peripherally fluorinated metallodendrimers 2G-(OTiCpSiFCl2)8 (4b) and 3G-(OTiCpSiFCl2)16 (6b). All metallodendrimers were characterized by multinuclear NMR spectroscopy. The suggested structures were supported by comparison with model 1-propoxycomplexes 10a,b. To identify side products of the alcoholysis reaction, hydrolytic behavior of the starting trichloro complexes was studied both in solid state and in solution. The main products of hydrolysis in solution were identified as μ-oxocomplexes 8a,b whereas hydrolysis in solid state yielded mainly hydroxycomplexes 7a,b.
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This work was supported by Ministry of Education, Youth and Sport of the Czech Republic (Grant LC06070). We gratefully acknowledge Dr. Jiří Horský and Ms. Zuzana Walterová (Institute of Macromolecular Chemistry of the ASCR, v.v.i.) for the measurement of MALDI-TOF MS.