Si(CH2CH2SnH3)4 — a unique organotin hydride featuring 12 SnH units in a dendritic molecule. Single-crystal X-ray structures of tetrakis(2-stannylethylene)silane and tetrakis[2-(triphenylstannyl)ethylene]silane

Fourfold hydrostannation of tetravinylsilane affords the first generation metallodendrimer Si(CH2CH2SnPh3)4 (1). Selective bromination yields Si(CH2CH2SnBr3)4 (2), which can be reduced by LiAlH4 to give Si(CH2CH2SnH3)4 (3), containing 12 reactive SnH bonds. These novel dendritic organotin compounds were characterized by elemental analysis, spectroscopic studies (1H-, 13C-, 119Sn-NMR; IR) and by single-crystal X-ray structure determination. The molecular structures of 1 and 3 reveal increased conformational constraint in 1; the average SnH bond length in 3 is 1.60(7) Å.