Meso ‐Carbon Atom Nucleophilic Attack Susceptibility in the Sterically Strained Antiaromatic Bis‐BODIPY Macrocycle and Extended Electron‐Deficient BODIPY Precursor**
Meso ‐Carbon Atom Nucleophilic Attack Susceptibility in the Sterically Strained Antiaromatic Bis‐BODIPY Macrocycle and Extended Electron‐Deficient BODIPY Precursor**
复制标题
空间应变反芳香族双 BODIPY 大环和扩展电子中的内消旋碳原子亲核攻击敏感性 - 缺陷 BODIPY 前体**
DOI：
10.1002/chem.202201261
复制
发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Nemykin, Victor N.
中科院分区：
文献类型：
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作者：
Zatsikha, Yuriy V.;Schrage, Briana R.;Blesener, Tanner S.;Harrison, Laurel A.;Ziegler, Christopher J.;Nemykin, Victor N.
本文制备了一个32π电子立体应变的双BODIPY大环，其中两个BODIPY片段由对二乙烯基苯基连接。与常规的BODIPYs不同，这个大环中的荧光被猝灭。大环核磁共振谱中的宽信号可以用对二乙烯苯片段的振动自由来解释。根据溶液和固态的变温EPR光谱，排除了大环可能的双根碱性质，这表明它的闭壳quinoidal结构。大环及其前体BODIPY二dede3中的meso - C−H键与THF形成弱氢键，易受有机胺和氰化物阴离子的亲核攻击。这种亲核攻击的反应产物具有eso - sp3碳原子，并通过核磁共振、质谱和X射线晶体学进行了表征。与最初的bis - BODIPY大环不同，加合物在400nm区域有很强的荧光。通过密度泛函理论（DFT）和时间相关DFT （TDDFT）计算，研究了新发色团的电子结构和光谱性质，并与实验数据有很好的相关性。
A sterically strained 32π‐electron antiaromatic bis‐BODIPY macrocycle in which two BODIPY fragments are linked byp‐divinylbenzene groups was prepared and characterized. Unlike regular BODIPYs, the fluorescence in this macrocycle is quenched. The broad signals in the NMR spectra of the macrocycle were explained by the vibronic freedom of thep‐divinylbenzene fragments. The possible diradicaloid nature of the macrocycle was excluded on the basis of variable‐temperature EPR spectra in solution and in solid state, which is indicative of its closed‐shell quinoidal structure. Themeso‐C−H bond in the macrocycle and its precursor BODIPY dialdehyde3forms a weak hydrogen bond with THF and is susceptible for the nucleophilic attack by organic amines and cyanide anion. The reaction products of such a nucleophilic attack havemeso‐sp3carbon atoms and were characterized by NMR, mass spectrometry and, in one case, X‐ray crystallography. Unlike the initial bis‐BODIPY macrocycle, the adducts have strong fluorescence in the 400 nm region. The electronic structure and spectroscopic properties of new chromophores were probed by density functional theory (DFT) and time‐dependent DFT (TDDFT) calculations and correlate well with the experimental data.