Single‐electron spodium bonds: Substituent effects

• Published in: Applied organometallic chemistry Vol. 37; no. 4
• Main Authors: Wu, Qiaozhuo, McDowell, Sean A. C., Li, Qingzhong
• Format: Journal Article
• Language: English
• Published: Chichester Wiley Subscription Services, Inc 01.04.2023
• Subjects: Bonding strength; Cadmium; Chemistry; Lewis acid; Lewis base; Mercury (metal); Methyl radical: AIM; NBO; Radicals; Spodium bond
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.7052

This study performed a theoretical exploration to predict and characterize the single‐electron spodium bond in the complexes of SpX2 (Sp = Zn, Cd, and Hg; X = H, F, Cl, Br, and CH3) with the H3C radical, in which the H3C radical serves as the Lewis base and the π‐hole on the Sp atom in SpX2 plays an acid role. The interaction energy varies in the range 7–30 kJ/mol, indicating that the Sp atom in SpX2 has a good affinity for the H3C radical. The spodium bond strength is not only dependent on the size of the Sp atom of SpX2 but is also affected by the substituent X in the Lewis acid. For most complexes, the spodium bond is stronger in the rank of Hg < Cd < Zn. The halogen substitution in SpX2 strengthens the spodium bond, whereas a weakening effect is found for the CH3 groups of Sp (CH3)2. Regardless of the interaction intensity, the single‐electron spodium bond exhibits the characteristics of a partially covalent interaction. A new type of spodium bond, single‐electron spodium bond, is proposed between the methyl radical molecule and the π‐hole on the Sp atom of SpX2 (Sp = Zn, Cd, and Hg; X = H, F, Cl, Br, and CH3). The strength of the spodium bond is not only dependent on the size of the Sp atom of SpX2 but is also affected by the substituent X in the Lewis acid.