Organometallics, 25 (14), 3428 -3434, 2006

Convergent Synthesis and Characterization of Organotin Dendrimers Sn{(CH₂)_nSn[(CH₂)₄SnPh₃]₃}₄ (n = 3, 4)

Herbert Schumann,* Yilmaz Aksu, and Birgit C. Wassermann

Abstract:

The reaction of the haloalkyltin trihalides Br(CH₂)₃SnBr₃ and Br(CH₂)₄SnBr₃ with 3 equiv of but-3-enylmagnesium bromide yielded Br(CH₂)₃Sn(CH₂CH₂CH=CH₂)₃ (3) and Br(CH₂)₄Sn(CH₂CH₂CH=CH₂)₃ (4). Both dendritic branches can be converted into their corresponding Grignard reagents, whose consequent treatment with 0.25 M amounts of SnCl₄₂)₃Sn(CH₂CH₂CH=CH₂)₃]₄ (5) and Sn[(CH₂)₄Sn(CH₂CH₂CH=CH₂)₃]₄ (6), respectively. The subsequent hydrostannation of 5 and 6 delivered Sn{(CH₂)₃Sn[(CH₂)₄SnPh₃]₃}₄ (7) and Sn{(CH₂)₄Sn[(CH₂)₄SnPh₃]₃}₄ (8) as dendrimers of the second generation. All compounds were characterized by elemental analysis, ¹H, ¹³C, and ¹¹⁹Sn NMR spectroscopy, and MALDI-TOF mass spectrometry. resulted in the formation of the dendrimers Sn[(CH