Carbosilane Metallodendrimers with Titanocene Dichloride End Groups

Carbosilane metallodendrimers containing substituted titanocene dichloride end groups were prepared using hydrosilylation as the capping reaction. Two complementary pathways were followed: hydrosilylation of ω-alkenyl-substituted titanocene dichloride complexes with Si–H bond terminated dendrimers and hydrosilylation of vinyl terminated dendritic materials with 3-(dimethylsilyl)­propyl-substituted titanocene dichloride. The former procedure provided dendrimers of the first generation with four end units and of the second generation with eight end units. The latter method gave dendrititic wedges and dendrimers up to the second generation with 16 peripheral titanocene dichloride units and molecular weight 7070 Da. Dendritic materials were purified by GPC and characterized by MALDI-TOF mass spectrometry and ESI-TOF mass spectrometry (metallodendrimers) and also by multinuclear NMR