Tribenzotriquinacenes Based on Regioselective Bis-formylation: Optical Resolution and Absolute Configuration of Inherently Chiral Derivatives and Synthesis of the First Cyclophane-Type Tribenzotriquinacene Dimers
Tribenzotriquinacenes Based on Regioselective Bis-formylation: Optical Resolution and Absolute Configuration of Inherently Chiral Derivatives and Synthesis of the First Cyclophane-Type Tribenzotriquinacene Dimers
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基于区域选择性双甲酰化的三苯并三醌：固有手性衍生物的光学分辨率和绝对构型以及第一个环芬型三苯并三醌二聚体的合成
DOI：
10.1002/chem.201001620
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发表时间：
2010-01-01
影响因子：
4.3
通讯作者：
Kuck, Dietmar
中科院分区：
文献类型：
--
作者：
Wang, Tao;Hou, Qin-Qing;Kuck, Dietmar
首次合成了对映体纯的含两个单官能化芳核的三苯并三喹并苯（TBTQs），并测定了它们的光学性质和绝对构型。完全桥头甲基化的母体TBTQ烃与MeOCHCl_2/TiCl_4的显著区域选择性双缩合得到两种C-s-对称（非手性）双官能化衍生物与一种C-1-对称（手性）异构体的混合物。还原和随后的柱色谱法提供了三种相应的苄基TBTQ二醇。通过（R）-1，1 '-联-2-萘酚醚的非对映异构体实现了外消旋2，6-双羟甲基衍生物的光学拆分，并通过CD激子模型分析确定了对映异构体的绝对构型。电子圆二色性（ECD）光谱和对映体的比旋光度与DFT计算结果一致。在C-s-对称异构体中，“近端”2，11-二醛和相应的苄二醇分别通过2D NMR光谱和X-射线晶体学分析进行了鉴定，并作为合成几种新型二硫杂环芳的起始点。这些包括第一种“二聚”三苯并三喹并苯基环番，其具有以顺式（凹-凹）或反式（凸-凹）构型彼此连接的两个TBTQ单元的碗。这种硫杂环芳作为不同金属离子的荧光化学传感器的有用性也被证明。
Enantiomerically pure tribenzotriquinacenes (TBTQs) bearing two monofunctionalized aromatic nuclei were synthesized for the first time and their optical properties and absolute configuration determined. A remarkably regioselective bis-formylation of the fully bridgehead methylated parent TBTQ hydrocarbon with MeOCHCl2/TiCl4 afforded a mixture of two C-s-symmetrical (achiral) difunctionalized derivatives together with one C-1-symmetrical (chiral) isomer. Reduction and subsequent column chromatography furnished the three respective benzylic TBTQ dialcohols. Optical resolution of the racemic 2,6-bis(hydroxymethyl) derivative was achieved via the diastereomeric (R)-1,1'-bi-2-naphthol ethers and the absolute configuration of the enantiomers was determined by CD exciton model analysis. The electronic circular dichroism (ECD) spectra and the specific rotation of the enantiomers were found to agree with the results of DFT calculations. Among the C-s-symmetrical isomers, the "proximal" 2,11-dialdehyde and the corresponding benzylic dialcohol were identified by 2D NMR spectroscopy and X-ray crystallographic analysis, respectively, and used as the starting point for the synthesis of several novel dithiametacyclophanes. These include the first "dimeric" tribenzotriquinacene-based cyclophanes bearing the bowls of the two TBTQ units attached to each other in a syn (concave-concave) or anti (convex-concave) configuration. The usefulness of such thiacyclophanes as fluorescent chemosensors for different metal ions is also demonstrated.