通过化物替代增强Chichibabin的碳化合物的二极端性质
Gargi Kundu1,2, Soumya Ranjan Dash2,3, Ravi Kumar2,3
1Inorganic Chemistry and Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road Pashan, Pune, 411008, India.
ChemPlusChem
|July 6, 2023
概括
这项研究报告了一种由5-SIDipp衍生的新型化物替代奇奇巴宾的碳化合物. 这种化合物与其替代对应物相比,具有显著较低的单元-三元能量差距和更高的二基性质.
科学领域:
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
- 计算化学的计算化学
背景情况:
- 在有机金属化学中,N-异环碳 (NHCs) 是多功能联体.
- 奇奇巴宾的碳化合物 (CHs) 以其独特的电子性质和二基性质而闻名.
- 化有机化合物具有独特的电子和物理特性.
研究的目的:
- 为了合成和表征一种新的用替代的基于5-SIDipp的奇奇巴宾的碳化合物.
- 为了研究合成化合物的电子性质,特别是单元-三元能量差距和二基性质.
- 通过量子化学计算,将这些特性与用替代的类似物进行比较.
主要方法:
- 通过双C-F键激活decafluorobiphenyl与5-SIDipp和BF3.3一起合成一种新的伊米达盐.
- 减少伊米达盐,以产生目标替代的5-SIDipp基奇奇巴宾的碳化合物.
- 量子化学计算 (B3LYP,CASSCF,CASPT2) 用于确定电子属性.
主要成果:
- 得到了合成的用替代的奇奇巴宾的碳化合物 (3).
- 量子化学计算显示了一个单元基态,单元-三元能量差距 (ΔE_S-T) 为3.7kcal mol−1 (B3LYP).
- 迪拉基特征 (y) 计算为0.62 (B3LYP),明显高于用替代的类似物 (0.41-0.43).
- 根据CASSCF和CASPT2的计算结果, ΔE_S-T值较高 (分别为22.24和11.17千卡的mol-1),二极根性 (d) 为44.6%.
结论:
- 通过八双烯间隔器引入原子影响了基于5-SIDipp的奇奇巴宾的碳化合物的电子特性.
- 与类似物相比,用替代的衍生品表现出增强的二基性质和减少的单基三基能量差距.
- 这些发现有助于理解NHC基激素和化有机材料中的结构性质关系.
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