Bharadwaz Priyam, Chetia Pubali, Phukan Ashwini K
Department of Chemical Sciences, Tezpur University, Napam, 784 028, Assam, India.
Chemistry. 2017 Jul 21;23(41):9926-9936. doi: 10.1002/chem.201701645. Epub 2017 Jul 3.
Quantum chemical calculations have been carried out to understand the ligand properties of skeletally modified cyclic alkyl amino carbenes. The stability of these carbenes has been assessed from an evaluation of their singlet-triplet and stabilization energy values. Ylide substituted carbenes are found to be more stable than non-ylidic ones in their optimized singlet state. Nucleophilicity and electrophilicity indices values were evaluated in order to further investigate the reactivity of these carbenes. The calculated values of proton affinities and the degree of gallium pyramidalization in the carbene-GaCl adducts correlate well with the σ-basicity of these carbenes. The reactivity of non-ylidic carbenes toward the activation of both H and NH are calculated to be more favourable compared to that of parent CAAC. On the other hand, ylide anchored carbenes are found to be unsuccessful toward the activation of both H and NH .
已进行量子化学计算以了解骨架修饰的环状烷基氨基卡宾的配体性质。通过评估这些卡宾的单重态-三重态和稳定能值来评估其稳定性。发现叶立德取代的卡宾在其优化的单重态下比非叶立德卡宾更稳定。评估亲核性和亲电性指数值以进一步研究这些卡宾的反应性。卡宾-GaCl加合物中质子亲和力的计算值和镓的锥化程度与这些卡宾的σ-碱性密切相关。计算得出，与母体CAAC相比，非叶立德卡宾对H和NH的活化反应性更有利。另一方面，发现叶立德锚定的卡宾对H和NH的活化均不成功。
