Reactivity of 2,6‐Dihalophenyl Lithium Reagents Towards Chlorosilanes. Synthesis and Structure of 2,3‐ and 2,6‐Dihalophenyl(di‐)silanes

摘要

> The reaction of 2,6‐dihalophenyllithium 2,6‐ X ₂ C ₆ H ₃ Li ( X = F, Cl, Br) with the chlorosilanes ClMe ₂ SiSiCl ₂ Me, SiCl ₄ , and HSiCl ₃ afforded the diaryldisilanes (2,6‐ X ₂ C ₆ H ₃ SiMe ₂ ) ₂ [ X = F ( 1a ), Cl ( 1b ), Br ( 1c )] and the diaryl‐ and triarylsilanes (2,6‐ X ₂ C ₆ H ₃ ) ₂ SiCl ₂ [ X = F ( 3a ), Cl ( 3a )], (2,3‐Br ₂ C ₆ H ₃ ) ₂ SiCl ₂ ( 4c ), (2,6‐F ₂ C ₆ H ₃ ) ₃ SiH ( 6a ), and (2,6‐ X ₂ C ₆ H ₃ ) ₂ Si(H)Cl [ X = Cl ( 7b ), Br ( 7c )], respectively. The formation of 4c was rationalized on the basis of an equilibrium that exists between the aryllithium isomers 2,6‐Br ₂ C ₆ H