Synthesis and reactions of highly sterically hindered organosilicon compounds of the type (Me3Si) 3CSi(C6H4OMe-p) 2X

Article abstract of DOI:10.1016/S0022-328X(97)00302-1

Reaction of TsiLi (Tsi = (Me₃Si)₃C) with (p-MeOC₆H₄)₂SiF₂ gave TsiSi(C₆H₄OMe-p)₂F, which was treated with LiAlH₄ to give (Me₃Si)₃CSi(C₆H₄OMe-p)₂H. Treatment of the latter with ICl in the presence of a large excess of Me₃SiC₆H₄OMe-p gave (Me₃Si)₃CSi(C₆H₄OMe-p)₂Cl rather than the expected (Me₃Si)₃CSi(C₆H₄OMe-p)₂I. Use of Br₂ in place of ICl gave (Me₃Si)₃CSi(C₆H₄OMe-p)₂Br. The fluoride (Me₃Si)₃CSi(C₆H₄OMe-p)₂F was found to react with NaOMe/MeOH and NaOEt/EtOH, to give (Me₃Si)₂CHSi(C₆H₄OMe-p)₂OMe and (Me₃Si)₂CHSi(C₆H₄OMe-p)₂OEt, respectively, and secondary products formed from them. Only secondary products were observed from the corresponding (prolonged) reactions in NaOPrⁱ/PrⁱOH, and KOBu^t/Bu^tOH. The diol (p-MeOC₆H₄)₂Si(OH)₂ was made by hydrolysis of (p-MeOC₆H₄)₂SiCl₂.