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具有不同双基性质的二合乙烯异构体:在单基双基中运用克拉尔的芳香六合规则
Zhe Sun1, Sangsu Lee, Kyu Hyung Park
1Department of Chemistry, National University of Singapore , 3 Science Drive 3, 117543 Singapore.
Journal of the American Chemical Society
|November 12, 2013
概括
克拉尔的芳香六重法则成功地预测了单个比拉迪卡洛伊德的基本状态. 更芳香的六环与更大的二基性质相关,影响近红外吸收等光学特性.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 克拉尔的芳香六合规则是为了预测多环芳香碳化合物的稳定性而建立的.
- 开的比拉迪卡洛伊德的地面状态受到芳香六环数的影响.
- 克拉尔法则对单体基类的适用性需要经验验证.
研究的目的:
- 为了调查Clar的芳香六重法则对单一的比拉迪卡洛因的有效性.
- 合成和表征具有不同芳香六环数的二合乙烯异构体 (DBHZ1和DBHZ2).
- 为了将芳香六环的数量与二基性质和光学特性相关联.
主要方法:
- 合成和分离DBHZ1和DBHZ2异构体.
- 使用核磁共振 (NMR),电子自旋共振 (ESR),SQUID,稳态和短暂吸收光谱 (TA) 的表征.
- 进行X射线晶体分析和不受限制的对称性破坏密度函数理论 (DFT) 计算.
主要成果:
- DBHZ2具有更芳香的六合环,具有比DBHZ1.1更高的二基性质.
- DBHZ2在近红外 (804 nm) 显示了强烈的单光子吸收和一个大的两个光子吸收截面 (2800 GM在1600 nm).
- 实验和计算数据证实了芳香六合数和二基性质之间的关系.
结论:
- 克拉尔的芳香六重法则可以扩展到预测单个比拉迪卡洛因的基态和比拉迪卡特.
- 芳香六合环的数量是比拉迪卡洛因性质的关键决定因素.
- 这项研究为设计具有量身定制光学特征的新型比拉迪卡洛伊德材料提供了基础.
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