Resonance-assisted intramolecular triel bonds
Resonance-assisted intramolecular triel bonds
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DOI：
10.1039/d2cp01244h
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发表时间：
2022-05-27
影响因子：
3.3
通讯作者：
Xie，Xiaoying
中科院分区：
文献类型：
--
作者：
Liu，Na;Li，Qingzhong;Xie，Xiaoying
通过对TrH_2-CRCR-CRS（Tr = Al，Ga，In; R = NO_2，CH_3）平面五元环的量子化学计算，考察了TrH_2-CRCR-CRS分子内Tr_2S三电子键共振增强的可能性.这个内部键被发现是相当短的（2.4-2.7 π），具有12和21 kcal mol−1之间的大键能。环内键长交替和原子电荷的模式与涉及共轭双键的共振一致。这种共振使三重键的强度提高了约25%。吸电子的NO2基团削弱了键，但它是由供电子的CH 3取代基加强。NICS分析表明环内存在一定程度的芳香性。
The possibility that the intramolecular Tr⋯S triel bond is strengthened by resonance is examined by quantum chemical calculations within the planar five-membered ring of TrH2–CRCR–CRS (Tr = Al, Ga, In; R = NO2, CH3). This internal bond is found to be rather short (2.4–2.7 Å) with a large bond energy between 12 and 21 kcal mol−1. The pattern of bond length alternation and atomic charges within the ring is consistent with resonance involving the conjugated double bonds. This resonance enhances the triel bond strength by some 25%. The electron-withdrawing NO2 group weakens the bond, but it is strengthened by the electron-donating CH3 substituent. NICS analysis suggests the presence of a certain degree of aromaticity within the ring.