Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States.
Inorg Chem. 2020 Dec 21;59(24):18241-18252. doi: 10.1021/acs.inorgchem.0c02721. Epub 2020 Dec 7.
Two brominated 10,10-dimethylisocorrole (10-DMIC) derivatives containing Pd(II) centers have been prepared and characterized. These compounds were prepared via bromination of 10,10-dimethylbiladiene-based oligotetrapyrroles. Bromination of free base 10,10-dimethylbiladiene () followed by metalation with Pd(OAc), as well as bromination of the corresponding Pd(II) dimethylbiladiene complex () provide routes to Pd(II) hexabromo-10,10-dimethyl-5,15-bis(pentafluorophenyl)-isocorrole (]) and Pd(II) octabromo-10,10-dimethyl-5,15-bis(pentafluorophenyl)-isocorrole (]). The solid-state structures of the two brominated isocorrole complexes are presented, as is that for a new decabrominated dimethylbiladiene derivative (). The electronic and spectroscopic properties of the brominated biladiene and isocorrole derivatives were probed using a combination of voltammetric methods and steady-state UV-vis absorption and emission experiments. Data obtained from these experiments allow the properties of the brominated biladiene and isocorrole derivatives to be compared to previously studied biladiene derivatives (., and ). CV and DPV experiments demonstrate that and support well-behaved multielectron redox chemistry, similar to that which has been observed for other nonaromatic tetrapyrroles containing sp-hybridized -carbons. Spectroscopic experiments reveal that bromination of the dimethylbiladiene core shifts this system's UV-vis absorption profile to lower energy and that the dimethylisocorrole complexes support panchromatic absorption profiles that extend across the UV-vis and into the near-IR region. Photosensitization experiments demonstrate that unlike previously studied Pd(II) biladiene constructs, , , and support limited triplet excited state chemistry with O, indicating that the novel nonaromatic tetrapyrrole derivatives described in this work may be best suited for applications other than singlet oxygen sensitization.
已经制备并表征了两个含有 Pd(II)中心的溴代 10,10-二甲基异corrole（10-DMIC）衍生物。这些化合物是通过 10,10-二甲基biladiene 为基础的寡聚四吡咯的溴化制备的。自由碱基 10,10-二甲基biladiene（）的溴化，随后用 Pd(OAc)金属化，以及相应的 Pd(II)二甲基biladiene 配合物（）的溴化，提供了 Pd(II)六溴-10,10-二甲基-5,15-双（五氟苯基）-异corrole（]）和 Pd(II)八溴-10,10-二甲基-5,15-双（五氟苯基）-异 corrole（]）的途径。呈现了两个溴代异 corrole 配合物的固态结构，以及一个新的十溴化二甲基biladiene 衍生物（）的结构。使用组合伏安法和稳态 UV-vis 吸收和发射实验研究了溴代 biladiene 和异 corrole 衍生物的电子和光谱性质。从这些实验中获得的数据允许比较溴代 biladiene 和异 corrole 衍生物的性质与以前研究过的 biladiene 衍生物（.，和）。CV 和 DPV 实验表明，和支持良好的多电子氧化还原化学，类似于已经观察到的其他含有 sp 杂化 - 碳的非芳香四吡咯。光谱实验表明，二甲基biladiene 核的溴化将该系统的 UV-vis 吸收谱移至更低的能量，并且二甲基异 corrole 配合物支持全色吸收谱，延伸到 UV-vis 并进入近红外区域。光致敏化实验表明，与以前研究过的 Pd(II)biladiene 结构不同，，，和支持有限的三重态激发态化学与 O，表明在这项工作中描述的新型非芳香四吡咯衍生物可能最适合于除单线态氧敏化以外的应用。
