| This thesis is mainly composed of three parts: the addition reactions of nitriles to amines catalyzed by divalent ytterbium complexes; the guanylation reactions of amines with carbodiimides catalyzed by divalent lanthanide complexes supported by a linked bis(phenolate) ligand; and the reaction of divalent ytterbium complex bearing a diamino bis(phenolate) ligand with the amine in the presence of sodium amide.1. Divalent ytterbium complexes including [Me2NCH2CH2N(CH2-2-O-3, 5-C6H2(But)2)2)Yb(THF)2] (1),[BunN(CH2-2-O-3, 5-C6H2 (But)2)2Yb(THF)3] (2),[2, 2′-CH2(OC6H3But-6-Me-4)2Yb(THF)3] (3),[Yb[N(TMS)2]2(THF)2] (4),[(2, 6-(But)2-4-MeC6H2O)2Yb(THF)3] (5),(MeC5H4)2Yb·DME (6) were tested for catalytic addition reaction of nitriles to amines. It was found that the selectivity for the reaction depended greatly on the structures of the divalent lanthanide complexes mentioned above. Using complex 1 as the catalyst, the products of monosubstituted N-arylamidines were obtained in good yields, while monosubstituted N-arylamidines together with triazine yielded when complexes 2-6 were used. The reaction conditions such as the temperature and the molar ratio of nitrile to amine also exhibited a great influence on the catalytic activity of complex 1.2. To address the mechanism for the reaction of nitriles to amines by divalent lanthanide complexes, reaction of complex 5 and PhCN in 1 : 1 molar ratio was conducted in toluene with trace of THF at room temperature for 12 h. The divalent lanthanide complex [(2, 6-(But)2-4-Me-C6H2O)2Yb(C6H5CN)(THF)2] (7) was isolated from the solution. The result indicated that the coordination of nitrile to the catalysts was the first step for the reaction of nitriles to amines catalyzed by divalent ytterbium complexes.3. Addition reaction of amines to carbodiimides catalyzed by the divalent ytterbium complexes bearing a linked bis(phenolate) ligand including complexes 1-3, complex [C4H7OCH2N(CH2-2-O-3,5-C6H2(But)2)2Yb(THF)2] (10) and [Me2NCH2CH2N(CH2-2- O-3, 5-C6H2(But)2)2Eu]2 (11) were investigated to examine the effects of both the structures of the bis(phenolate) ligands and the central metals on the reactivity. It was found that the reactivity orders are [Me2NCH2CH2N(CH2-2-O-3,5-C6H2(But)2)2] > [BunN(CH2-2-O-3,5-C6H2(But)2)2] > [C4H7OCH2N(CH2-2-O-3,5-C6H2(But)2)2] > [2, 2′-CH2(OC6H3But-6-Me-4)2] for ligands and Yb > Eu for central metals. Moreover, the temperature affected the catalytic activity, that is, increasing temperature led to the increase of the yields. 4. The reaction of complex 1, 2, 6-Me2PhNHNa and 2, 6-Me2PhNH2 in 1 : 1 : 1 molar ratio afforded the anionic trivalent lanthanide amide [Me2NCH2CH2N(CH2-2-O-3, 5-C6H2(But)2)2)Yb(2, 6-Me2PhNH)2(Na+)(DME)]2(DME) (12). The result suggested that reduction of amine can be occurred using divalent lanthanide complex 1 in the presence of sodium amide.
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