作者:Zhenjun Si、Xiaona Li、Xiyan Li、Guohai Xu、Chenling Pan、Zhiyong Guo、Hongjie Zhang、Liang Zhou
DOI:10.1039/b912939a
日期:——
Four novel diimine rhenium(I) carbonyl complexes with the formula [Re(CO)3(L)Br], where L = 2-(4-(9H-carbazol-9-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (P1), 2-(4-(3,6-di-tert-butyl-9H-carbazol-9-yl)phenyl)-1H-imidazo-[4,5-f][1,10]phenanthroline (P2), 2-(4-(6-(9H-carbazol-9-yl)-9H-3,9′-bicarbazol-9-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (D1), and 2-(4-(3′,6′-di-tert-butyl-6-(3,6-di-tert-butyl-9H-carbazol-9-yl)-9H-3,9′-bicarbazol-9-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (D2), have been successfully synthesized and fully characterized by 1H NMR, IR, and UV–Vis, etc. The luminescence quantum yields (LQYs) of the parent Re(I) complexes P1 and P2 are 0.13 and 0.16, respectively, which are much higher than the previously reported Re(I) dendrimers. The HOMOs and the LUMOs of P1 and P2 are calculated to be mainly composed of [d(Re) + π(CO + Br)] and π*(L) orbital, respectively. However, those of the Re(I) dendrimers D1 (LQY = 0.066) and D2 (LQY = 0.0048) are mainly localized on ligand L, indicating that the component of the metal-to-ligand charge-transfer dπ (Re) →π*(N–N) (MLCT) transitions in P1 and P2 should be more than those in D1 and D2. As a result, the higher LQYs of P1 and P2 are tentatively assigned to the disturbance of the MLCT transitions during the photoluminescence process.
四种新型二亚胺铼(I)羰基配合物,其式为[Re(CO)3(L)Br],其中 L = 2-(4-(9H-咔唑-9-基)苯基)-1H-咪唑并[4,5-f][1、10]phenanthroline (P1), 2-(4-(3,6-di-tert-butyl-9H-carbazol-9-yl)phenyl)-1H-imidazo-[4,5-f][1,10]phenanthroline (P2), 2-(4-(6-(9H-carbazol-9-yl)-9H-3,9′-bicarbazol-9-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (D1), and 2-(4-(3′,6′-di-tert-butyl-6-(3,6-di-tert-butyl-9H-carbazol-9-yl)-9H-3,(3′,6′-二叔丁基-6-(3,6-二叔丁基-9H-咔唑-9-基)-9H-3, 9′-联咔唑-9-基)苯基)-1H-咪唑并[4,5-f][1,10]菲罗啉(D2)成功合成,并通过 1H NMR、IR 和 UV-Vis 等对其进行了全面表征。母体 Re(I) 复合物 P1 和 P2 的发光量子产率(LQYs)分别为 0.13 和 0.16,远高于之前报道的 Re(I) 树枝状化合物。根据计算,P1 和 P2 的 HOMO 和 LUMO 分别主要由[d(Re) + π(CO + Br)] 和 π*(L)轨道组成。然而,Re(I) 树枝形分子 D1(LQY = 0.066)和 D2(LQY = 0.0048)的电荷转移主要集中在配体 L 上,这表明 P1 和 P2 中金属-配体电荷转移 dπ (Re) →π*(N-N) (MLCT)跃迁的分量应多于 D1 和 D2。因此,P1 和 P2 较高的 LQY 暂定为光致发光过程中 MLCT 过渡的干扰所致。