9-Borylanthracene 12 was prepared from 1,8-bis(diisopropylphosphino)-9-bromoanthracene (5) and the X-ray structure of 12 shows a tetrahedral boron atom coordinated by only one of the two (i-Pr)2P groups. However, anthracene protons were observed symmetrically in 1H NMR even at −80 °C, clearly indicating that the intramolecular bond-switching process is taking place very rapidly in solution.
9-
硼基
蒽(12)是由1,8-双(异丙基
磷基)-
9-溴蒽(5)制得的,12的X射线结构显示一个四面体的
硼原子仅与两个(i-Pr)2P基团中的一个配位。然而,即使在−80 °C时,
蒽的质子在1H NMR中依然对称观察到,这清楚表明分子内的键切换过程在溶液中发生得非常迅速。