Synthesis and Properties of Antimony Compounds of the Type Sb(OSiR₃)₃

Abstract

Novel organoantimony compounds of the type Sb (0SiR₃)₃ [2, R¹=R²=R³= Pr; 3, R¹=R²=R³=i-Pr; 4, R¹=R²= Me, R³ = t -Bu; 5, R¹=R²=R³= Ph] were prepared in 4 1 8 1% yields by the reaction of SbCl₃ with NaOiR₃ (3 molar amounts) in toluene. These compounds were characterized by IR, ¹H, ¹³C, and ²⁹Si-NMR, and MS spectroscopy. According to MS and NMR spectral data, each compound ap pears to be a monomer. They are subject to hydrolysis at room temperature. Thus, treatment of the com pounds 1-4 with a large excess of H₂O under slightly forced conditions resulted in the formation of the corresponding silanols and antimony trioxides. IR and XPD data suggest the resulting antimony trioxides have two polymorph; the first polymorph is senarmontite obtained by hydrolysis of the corn pounds 1-4 in H₂O/CH₃OH and the second polymorph is valentinite given by hydrolysis of 3 and 4 in H₂O/CH₃COCH₃.