Zhang Yongliang, Wei Junnian, Chi Yue, Zhang Xuan, Zhang Wen-Xiong, Xi Zhenfeng
Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University , Beijing 100871, China.
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry (SIOC) , Shanghai 200032, China.
J Am Chem Soc. 2017 Apr 12;139(14):5039-5042. doi: 10.1021/jacs.7b02039. Epub 2017 Apr 4.
Since the concept of aromaticity represents one of the most fundamental principles in chemistry, the search for unprecedented and exciting aromatic systems, therefore, continues to drive research in this area. Herein we report the synthesis and characterization of spiro metalla-aromatics, in which the transition metal (Pd, Pt, or Rh) is the spiro atom, that cross-conjugates two aromatic five-membered metallacycles. These spiro metalla-aromatics tend to take square planar geometries, with the dihedral angle being influenced by the steric repulsion between the α-positioned substituents. Rationalized and classified via both experimental measurements (X-ray structural analysis, NMR spectroscopy, XPS, etc.) and theoretical analysis (DFT calculation, ISE, AICD, NICS, and CMOs), all these fundamental observations extend the concept of aromaticity and organometallic chemistry.
由于芳香性概念是化学中最基本的原理之一，因此，对前所未有的、令人兴奋的芳香体系的探索继续推动着该领域的研究。在此，我们报道了螺环金属芳烃的合成与表征，其中过渡金属（钯、铂或铑）为螺环原子，它使两个芳香五元金属环交叉共轭。这些螺环金属芳烃倾向于采取平面正方形几何构型，二面角受α位取代基之间的空间排斥作用影响。通过实验测量（X射线结构分析、核磁共振光谱、X射线光电子能谱等）和理论分析（密度泛函理论计算、诱导效应指数、原子诱导电流密度、核独立化学位移和定域分子轨道）进行合理化和分类，所有这些基本观察结果扩展了芳香性和有机金属化学的概念。
