The preparation and characterization of a series of niobium(V) complexes that incorporate the linear-linked aryloxide trimers 2,6-bis (4,6-dimethylsalicyl)-4-tert-butyl phenol [H-3(Me-L)] and 2,6-bis(4-methyl-6-tert-butylsalicyl)-4-tertbutylphenol [H-3(Bu-t-L)] are described. The chloride complex [Nb(Me-L)Cl-2](2) (1) was prepared in high yield by reaction of NbCl5 with H-3(Me-L) in toluene. In contrast, the analogous reaction with H-3(Bu-t-L) gave a mixture of [Nb(Bu-t-L)Cl-2](2) (2) and [Nb(de-Bu-t-L)Cl-2](2) (3a). During the formation of 3a, one of tert-butyl groups at the ortho position in the tBu-L ligand was lost. When the NbCl5(H-3(Bu-t-L) reaction was carried out in acetonitrile, Nb[H(Bu-t-L)]Cl-3(NCMe) (4) was obtained. Heating a solution of 4 in toluene generated 2 and 3a. The isolated complex 4 underwent ligand redistribution in acetonitrile to produce Nb[H(Bu-t-L)](2)Cl(NCMe) (5). Treatment of NbCl5 with Li-3(Bu-t-L) in toluene afforded 2. The chloride ligands in 1 and 2 smoothly reacted with 4 equiv of MeMgl and (LiSBu)-Bu-t, resulting in [Nb(R-L)Me-2](2) [R = Me (6), Bu-t (7)] and Nb(Me-L)((SBu)-Bu-t)(2) (8), respectively. A number of the above complexes have been characterized by X-ray crystallography. In the structures of 1, 2, and 6, the R-L ligand is bound to the metal center with a U-coordination mode, while an alternative S-conformation is adopted for 3a and 8. Complexes 4 and 5 contain a bidentate H(Bu-t-L) diphenoxide-monophenol ligand.