Synthesis of meso-Free Decaphyrin(1.1.1.1.1.1.1.1.1.1) by a Hydrodebromination Protocol; Aromaticity and Solvent-Polarity Dependent Conformational Change
Synthesis of meso-Free Decaphyrin(1.1.1.1.1.1.1.1.1.1) by a Hydrodebromination Protocol; Aromaticity and Solvent-Polarity Dependent Conformational Change
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通过加氢脱溴方案合成无内消旋十卡菲林(1.1.1.1.1.1.1.1.1.1)；
DOI：
10.1002/chem.202202682
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
A. Osuka
中科院分区：
文献类型：
--
作者：
A. Nakai;H. Saito;H. Yorimitsu;T. Tanaka;A. Osuka
通过[2+3+2+3]型酸催化交叉缩合和随后的氧化反应，合成了不含氨基的β-溴去氢呋喃。在四甲基二乙二胺和钯催化剂的催化下，该四溴脱氢卟啉与NaBH4进行加氢脱溴反应，得到了β未取代的不含双原子的[46]脱溴卟啉(1.1.1.1.1.1.1.1.1)，这是第一个吡咯单元数大于8的β未取代的无中位规则扩展卟啉的例子。它表现出明显的芳香性，源于它的46π共轭电子电路和灵活的非扭曲和双扭曲形式之间的构象变化，取决于溶剂的极性。通过实验和理论研究相结合的方法分析了它们的不同构象。
Ameso‐freeβ‐bromodecaphyrin has been constructed by [2+3+2+3] type acid‐catalyzed cross‐condensation and subsequent oxidation. Hydrodebromination of this tetrabromodecaphyrin with NaBH4in the presence of TMEDA and palladium catalyst affordedβ‐unsubstituted doublymeso‐free [46]decaphyrin(1.1.1.1.1.1.1.1.1.1) as the first example ofβ‐unsubstitutedmeso‐free regular expanded porphyrins with the number of pyrrole units larger than eight. It exhibits distinct aromaticity originating from its 46π‐conjugated electronic circuit and flexible conformational change between non‐twisted and doubly twisted forms depending on the solvent‐polarity. Their distinct conformations have been analyzed by combined experimental and theoretical investigations.