新型不對稱吡啶胺配基及其鎳金屬串與雙核釕錯合物之合成與研究

Abstract

本論文研究內容為新型不對稱含氧配基 H2ppap 之金屬串錯合物 cis-[Ni3(ppap)2(H2appp)] (1) 和雙核釕金屬錯合物 [Ru2(Hppap)3Cl2](BF4) (2)、[Ru2(Hppap)3Cl2] (3) 之合成、結構解析與性質量測 (H2ppap = 6-(5-phenylpyridyl)-amino-2-acetylamino-pyridine, H3appp = 6-amino- (5-phenylpyridyl)-2-pyridylamine )。 三核鎳金屬串錯合物 1，其中心的 Ni(II) 離子具有平面四方形的配位環境，與 H2ppap 配基中胺基上的氮鍵結，藉由 Ni—N 之鍵長比較，發現 Ni—Namido 鍵長較短，在 1.879 ~ 1.894 Å 之間，可知中心的 Ni(II) 為低自旋電子組態 (S = 0)，而末端的 Ni(II) 離子則具有四角錐的配位環境，其平均 Ni—Npyridine 鍵長較長，在 2.069 ~ 2.095 Å 之間，另外，Ni—Ni 距離為 2.364 Å。 從磁性量測結果可得知錯合物 1 和 2 皆為反鐵磁性。另外，由循環伏安法得知錯合物 2 在氧化部份於 E1/2 = 0.12 V 有ㄧ對可逆的氧化還原對，其表示 [Ru2]6+ 還原ㄧ個電子變成 [Ru2]5+ 的過程。

This study demonstrates the synthesis, crystal structure and properties of a novel asymmetrical metal string complex, cis-[Ni3(ppap)2(H2appp)2] (1), and di-nuclear ruthenium metal complexes, [Ru2(Hppap)3Cl2](BF4) (2) and [Ru2(Hppap)3Cl2] (3), supported by oxygen-containing H2ppap ligand (H2ppap = 6-(5-phenylpyridyl)-amino-2-acetylamino-pyridine, H3appp = 6-amino-(5-phenylpyridyl)-2-pyridylamine ). For the trinickel metal string complex 1, the central Ni2+ ion is square planar with four short Ni—Namido distances at a range of 1.879 - 1.894 Å, indicating a low-spin (S = 0) square planar Ni2+ configuration. Two terminal Ni2+ ions are in a square pyramidal environment with average Ni—Npyridine distances in the range of 2.069 - 2.095 Å. The averaged Ni—Ni distances in 1 are 2.364 Å. The magnetic susceptibility measurements in the solid state show that both complex 1 and 2 have an antiferromagnetic interaction. The electrochemistry of complex 2 is investigated by cyclic voltammetry. It exhibits one electrochemically reversible one-electron redox process at E1/2 = 0.12 V in CH2Cl2 containing 0.1 M TBAP. The E1/2 = 0.12 V is described as the one-electron reduction for [Ru2]6+/[Ru2]5+ process.