Syntheses and Electronic Properties of the Nickel and Palladium Complexes of the Octaethylporphyrin(M1)-(Dihexylbithiophene)_n-Octaethylporphyrin(M2) System [OEP(M1)-(DHBTh)_n-OEP(M2)] Connected with the Diacetylene Linkage. A Methodology for Molecular De

总结了OEP(M)-DHBTh-OEP(M)体系对称性和非对称性配合物的合成方法。特别值得注意的是，末端乙炔42和51的合成成功将导致一种通用的合成方法，并将推动本研究进入进一步的应用阶段。~1H核磁共振研究证实，所有的OEP(M)-(DHBTh)_n-OEP(M)衍生物都具有相当简单的骨架特征，无论分子的对称性如何，OEP(M)在36和37中的环电流在很大程度上保持不变。因此，OEP(M)的各向异性效应的脱除面积对于Ni络合物扩展到25Å，对于Pd络合物扩展到30Å，反映了它们的环电流的大小(图3)。红外光谱测量结果表明，TT系列的二乙炔键对EXT…的贡献较大无论DHBTh的数目多少，与OEP和DHBTh核的共振结构的尺寸都更大。与刚性和直链分子骨架的简单规律性相比，本π-电子共轭体系具有特征吸收光谱特征，反映了多种结构元素。Soret和Q带的出现是目前一维扩展的π-电子共轭体系所特有的，它准确地反映了DHBTh的取向。HH、HT和TT异构体1-3的吸收光谱显示各自的SORET谱带规则地分裂为两个主要的π→π*跃迁，其中所有较短波长的λ_1谱带都出现在440 nm左右。然而，在45 nm的范围内，较长的波长λ_2带分别出现在较长的波长区域。与相应的镍配合物1和3相比，在HH和TT系列中，Pd配合物4和5的光谱都有轻微的亚色位移和锐化。还证明了在36和37中引入(DHBTh)_n形成OEP(M)-(DHBTh)_n-OEP(M)(8-25)导致两个主要电子结构之间的逐步转变，反映了DHBTh的取向和n。随着n的增加，HH系列是OEP(M)-HTH和HTH-HH(DHBTh)_&lt；n-2&gt；-HTH之间的结合电子体系，而TT系列是OEP(M)-TT(DHBTh)_&lt；n-2&gt；之间的共轭体系(图10)。观察到了OEP(Ni)-TT(DHBTh)-OEP(Pd)衍生物7的溶剂依赖性光谱，但敏感带到溶剂极性的跃迁来源还有待进一步阐明。在DHBTh取向的同时，通过引入不同的OEP(M)环的不对称化也可能有效地将电子从一侧转移到另一侧。因此，OEP(M1)-(DHBTh)_n-OEP(M2)体系的电子吸收光谱可能受到以下结构元素的很大影响。从物质的角度来看，DHBTh的取向可以看作是构建体系主要电子结构的功能选择器，引入的金属离子M可以作为调节各功能带跃迁能的调制工具，DHBTh的数目可以作为精细调谐器来选择对外界电子刺激的敏感性。因此，通过有目的地选择这三个结构元素，可以构造出与特定电子性质相对应的OEP(M1)-(DHBTh)n-OEP(M2)的特定电子结构。由于结构元素可以分别扩展到DABTh、许多其他金属离子和更大数目的n的取向，本研究将为在分子设计阶段构建各种DABTh衍生物的特殊电子结构提供一种方法。较少

The synthetic methods for both symmetrical and unsymmetrical complexes of the OEP(M)-DHBTh-OEP(M) system have been conclusively described. Particularly, it is notable that the synthetic success of the terminal acetylenes 42 and 51 would lead to a general synthetic method for a variety of the OEP(M)-DHBTh-(π-EC) derivatives and would impel the present research onto the further application stage. ^1H NMR spectral study makes it confirmed that all the OEP(M)-(DHBTh)_n-OEP(M) derivatives possess the fairly simple skeletal features, regardless of the symmetry of molecule, with the respective ring currents of OEP(M) in 36 and 37 remaining to a great extent. And thus, the deshielded area from anisotropic effect of OEP(M) has proven to expand up to 25Å for the Ni complexes and 30Åfor the Pd complexes, reflecting the magnitudes of their ring currents (Fig.3). From the IR spectral measurements, it is derived that the diacetylene linkage for the TT series exhibits a greater contribution to an ext … More ension of the resonance structure with the OEP and DHBTh nuclei, regardless of the number of DHBTh. As contrasted with such a simple regularity in a rigid and straight molecular skeleton, the present π-electronic conjugation system possess characteristic absorption spectral features, reflecting several structure elements. The appearances of Soret and Q bands are peculiar to the present one-dimensionally extended π-electronic conjugation system, which exactly reflect the orientation of DHBTh. Absorption spectra for the HH,HT and TT isomers 1-3 show the respective Soret bands to split into two mainπ→π* transitions regularly, among which all the shorter wavelength λ_1 bands appear at around 440nm. The longer wavelength λ_2 bands, however, appear at the longer wavelength region separately over a range of 45nm. In both HH and TT series, the spectra of the Pd complexes 4 and 5 exhibit slight hypsochromic shift and sharpened, as compared with those for the corresponding Ni complexes 1 and 3. It is also proved that the introduction of (DHBTh)_n into 36 and 37 to form OEP(M)-(DHBTh)_n-OEP(M) (8-25) induces the gradual reformation between the two main electronic structures, reflecting both the orientation and n of DHBTh. With increases of n, the HH series the combined electronic system between OEP(M)-HTh and HTh-HH(DHBTh)_<n-2>-HTh, while the TT series does the conjugation system between OEP(M)-TT(DHBTh) and TT(DHBTh) _<n-2> (Fig.10). The solvent-dependent spectra of the OEP(Ni)-TT(DHBTh)-OEP(Pd) derivative 7 have been remarkably observed, though the transition origins of the sensitive bands to the solvent polarity must be further clarified. Concurrently with the orientation of DHBTh, the unsymmetrization by introducing the different OEP(M) rings into the present system is also potentially effective to conduct the electron transfer functionality from one side to the other.In consequence, the electronic absorption spectra of the OEP(M1)-(DHBTh)_n-OEP(M2) system could be affected substantially by the following structure elements. Putting those structure elements together from the material viewpoint, the orientation of DHBTh could be regarded as a function selector to construct the main electronic structure of the system, the incorporated metal ions M as a modulation tool for adjustment of the transition energy for each function band and the number of DHBTh as a fine tuner to select the susceptibility to the external electronic stimulations. Therefore, a particular electronic structure of OEP(M1)-(DHBTh)_n-OEP(M2) corresponding to the particular electronic property would be constructed by choosing these three structure elements purposively. Since the structure elements could be generalized to expand into the orientations of DABTh, many other metal ions and the greater numbers of n, respectively, the present study would provide a methodology for construction of the particular electronic structures of various DABTh derivatives at the stage of molecular design. Less