Synthesis and structural characterization of tris(2-mercapto-1-adamantylimidazolyl)hydroborato complexes: a sterically demanding tripodal [S3] donor ligand

The tris(2-mercapto-1-adamantylimidazolyl)hydroborato ligand, [Tm(Ad)], has been synthesized via the reaction of 1-adamantyl-2-mercaptoimidazole with MBH(4) (M = Li, K). [Tm(Ad)]M has been used to synthesize a variety of compounds of the main-group and transition elements, including [Tm(Ad)]ZnI, {[Tm(Ad)]GaI}[GaI(4)], {[Tm(Ad)]GaCl}[GaCl(4)], {[Tm(Ad)]GaGa[Tm(Ad)]}[GaCl(4)](2), {[Tm(Ad)](2)In}[InI(4)], [Tm(Ad)]In(κ(2)-mim(Ad))Cl, [Tm(Ad)]Ga→B(C(6)F(5))(3), [Tm(Ad)]In→B(C(6)F(5))(3), and [Tm(Ad)]Re(CO)(3). Structural characterization of [Tm(Ad)]Re(CO)(3) demonstrates that the [Tm(Ad)] ligand is more encapsulating than other [Tm(R)] ligands, including [Tm(Bu(t))], while IR spectroscopic studies indicate that the [Tm(Ad)] and [Tm(Bu(t))] ligands have very similar electron-donating properties.