Metal-dependent reactions of bulky metal(II) amides M[N(SiMe3)2]2 with 3,3′-disubstituted binaphthols (HO)2C20H10(SiR3)2-3,3′:: Selective conversion of one equivalent -OH group to a silyl ether -OSiMe3

The outcome of the reaction of the bulky metal(II) amides M[N(SiMe3)(2)](2)center dot nTHF (M = Be, Zn, Ge, Sn, n = 0; M = Mg, Ca, n = 2) with (R)-3,3'-bis(trimethylsilyl)-1,1'-bi-2,2'-naphthol ((R)-1) or (S)-3,3'-bis(dimethylphenylsilyl)1,1'-bi-2,2'-naphthol ((S)-9) depends on the identity of the metal and the nature of the 3,3'-substituents. When M = Be, Zn, or Ge, these amides serve as useful silylation agents that convert only one of the equivalent hydroxyl groups of the binaphthol (R)-1 to a trimethylsilyl ether, whereas the reactions of (R)-1 with the Mg, Ca, or,Sn amides generate a polynuclear complex. The reaction pathway for these interconversions was qualitatively monitored using NMR (H-1 and Be-9) spectroscopy. Treatment of Ge[N(SiMe3)(2)](2) with (S)-9 yields both a silyl ether and the chelated germanium(II) binaphthoxicle (S)-[Ge(O2C20H10(SiMe2Ph)(2)-3,3')(NH3)], which was structurally characterized.