Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany).
Angew Chem Int Ed Engl. 2014 Jul 7;53(28):7360-3. doi: 10.1002/anie.201403514. Epub 2014 Jun 10.
Utilizing a cyclic (alkyl)(amino)carbene (CAAC) as a ligand, neutral CAAC-stabilized radicals containing a boryl functionality could be prepared by reduction of the corresponding haloborane adducts. The radical species with a duryl substituent was fully characterized by single-crystal X-ray structural analysis, EPR spectroscopy, and DFT calculations. Compared to known neutral boryl radicals, the isolated radical species showed larger spin density on the boron atom. Furthermore, the compound that was isolated is extraordinarily stable to high temperatures under inert conditions, both in solution and in the solid state. Electrochemical investigations of the radical suggest the possibility to generate a stable formal boryl anion species.
利用环状（烷基）（氨基）卡宾（CAAC）作为配体，可以通过还原相应的卤硼烷加合物来制备含硼基官能团的中性 CAAC 稳定自由基。带有二茂基取代基的自由基物种通过单晶 X 射线结构分析、EPR 光谱和 DFT 计算得到了充分的表征。与已知的中性硼基自由基相比，分离出的自由基物种在硼原子上显示出更大的自旋密度。此外，在惰性条件下，无论是在溶液中还是在固态下，分离出的化合物对高温都具有极高的稳定性。自由基的电化学研究表明，有可能生成稳定的形式硼基阴离子物种。
