Bulky Amidinate Complexes of Indium(III). Synthesis and Structure of [CyNC((t)Bu)NCy](2)InCl.

Abstract

Reaction of 2 equiv of lithium dicyclohexylacetamidinate with InCl(3) affords the new species In[CyNC(Me)NCy](2)Cl (Cy = cyclohexyl) (1). Compound 1 reacts with MeLi to yield In[CyNC(Me)NCy](2)CH(3) (2) and also reacts with a third equivalent of amidinate to yield In[CyNC(Me)NCy](3) (3). Two new bulky amidinate ligands are prepared by the addition of (t)BuLi to CyN=C=NCy and Me(3)SiN=C=CSiMe(3), respectively. Subsequent reactions with InCl(3) lead to the high-yield syntheses of In[CyNC(CMe(3))NCy](2)Cl (4) and [Me(3)SiN(CMe(3))NSiMe(3)](2)InCl (5). Spectroscopic and elemental analyses confirm the formulas of all of these new species. Compound 4 is further characterized by X-ray crystallography and shown to possess a distorted trigonal bipyramidal coordination geometry around the metal center with the chloride group in the equatorial position. Crystal data for 4: triclinic, P&onemacr;, a = 12.545(7) Å, b = 13.482(8) Å, c = 11.965(6) Å, alpha = 102.08(5) degrees, beta = 92.00(5) degrees, gamma = 64.36(4) degrees, Z = 2, R = 0.029, R(w) = 0.045.