SIMPLIFIED APPROACH TO SILAANTHRONES AND DISILAANTHRACENES

Article abstract of DOI:10.1016/0022-328X(84)85185-2

An improved synthesis of bis(o-chlorophenyl)methylsilane is reported from reaction of a mixture of o-BrC6H4Cl and MeSiHCl2 with Mg shavings in THF.The diarylsilanes, (o-ClC6H4)2SiMeR (R = H, Me) could be converted to diGrignard reagents with Mg prepared by the Rieke method but not from commercial Mg (shavings or mesh).The diorganomatallic reagents generated from (o-XC6H4)2SiMeR (R = H, Me) are used to prepare disilaanthracenes or silaanthrones.A new spiro derivative, bis(dimethyl-o,o'-diphenylsilyl)spirosilane, is obtained on addition of HSiCl3 to the diGrignard reagent generated from (o-ClC6H4)2SiMe2.When gaseous CO2 is added to the dilithio reagent formed from (o-BNrC6H4)2SiMe2, silaanthrone is produced which provides a new route to the silaanthracene framework.Aspects of this new ring closure route are described.