The dilithiated boraamidinate complexes [Li-2{PhB(NDiPP)(2)}(THF)(3)] (7a) (Dipp = 2,6-diisopropylphenyl) and [Li-2{PhB(NDipp)((NBu)-Bu-t)}(OEt2)(2)] (7b), prepared by reaction of PhB[N(H)Dipp][N(H)R'] (6a, R' = Dipp; 6b, R' = Bu-t) with 2 equiv of (BuLi)-Bu-n, are shown by X-ray crystallography to have monomeric structures with two terminal and one bridging THF ligands (7a) or two terminal OEt2 ligands (7b). The derivative 7a is used to prepare the spirocyclic group 13 derivative [Li(OEt2)(4)][In{PhB(NDipp)(2)}(2)] (8a) that is shown by an X-ray structural analysis to be a solvent-separated ion pair. The monoamino derivative PhBCl[N(H)Dipp] (9a), obtained by the reaction of PhBCl2 with 2 equiv of DippNH(2), serves as a precursor for the synthesis of the four-membered BNCN ring {[R'''N(H)](Ph)-B(mu-(NBu)-Bu-1)(2)(CBu)-Bu-n} (10a, R'''= Dipp). The X-ray structures of 6a, 9a, and 10a have been determined. The related derivative 10b (R'''= Bu-t) was synthesized by the reaction of {Cl(Ph)B(mu-(NBU)-B-t)(2)(CBu)-Bu-n} with Li[N(H)Bu-t] and characterized by H-1, B-11, and C-13 NIVR spectra. In contrast to 10a and 10b, NMR spectroscopic data indicate that the derivatives {[DippN(H)](Ph)B(NR')(2)CR(NR')} (11a: R = Bu-t, R' = Cy; 11b: R = Bu-n, R' = Dipp) adopt acyclic structures with three-coordinate boron atoms. Monolithiation of 10a produces the novel hybrid boraamidinate/ amidinate (bamam) ligand {Li[DippN]PhB((NBu)-Bu-t)(CBu)-Bu-n((NBu)-Bu-t)} (12a).