| Summary: | 碩士 === 國立臺灣大學 === 化學研究所 === 102 === With the use of N2,N7-bis(4-methoxyphenyl)-1,8-naphthyridine-2,7-diamine (H2DAniDANy), a symmetrical tetradentate ligand, new series of HMSCs, [Ru2(HDAniDANy)4]( BF4) (1A), [Ru2Co(DAniDANy)3(HDAniDANy)] (1B), [CoRu2Co(DAniDANy)4](BF4) (1C), [Ru2(DAniDANy)(HDAniDANy)3](PF6) (1D), [Rh2(HDAniDANy)4] (2A) and [Rh2Co(DAniDANy)(HDAniDANy)3](BF4) (2B) were synthesized. From the experimental results of X-Ray crystallography and magnetic measurements, we can assign the charges of metal ions in these HMSCs. Complex 2B possesses the shortest heterometallic distance (Rh-Co 2.69 A) among these HMSCs, followed by complex 1C (Ru-Co 2.80 A) and complex 1B (Ru-Co 3.25 A). The heterometallic distance in complex 2B (Rh-Co 2.69 A) lies slightly outside the Co-Co (2.265 - 2.374 A) and Rh-Rh (2.389 - 2.570 A), may indicate the existence of heterometallic bond. But judge from the magnetic data, the dirhodium (II, II) unit and cobalt (II) are two independent metallic centers, there is no interaction between the 4d orbital in Rh and 3d orbital in Co. So there is no heterometallic bond in complex 2B. The decrease in heterometallic distance must result from the decrease in electric repulsion between the dirhodium (II, II) unit and cobalt (II) in complex 2B, compared to the more positive diruthenium (II,III) unit and cobalt (II) in complexes 1B and 1C.
Furthermore, we know that complex 1B is the reaction intermediate in the synthesis of complex 1C. So from the analysis of the crystal structure of complexes 1A, 1B and 1C, we can know that the reaction mechanism of the synthesis of HMSC 1C include ligand displacement, ligand deprotonation and metal coordination. For the Rh and Co HMSCs in this thesis, we lack the X-Ray crystallography data of tetranuclear HMSC. But judge from the analysis of the crystal structure of complexes 1A, 1B, 2A and 2B, it’s very likely that the synthesis of Rh and Co HSMCs undergoes the same mechanism as Ru and Co HSMCs.
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