New monodentate and bidentate silylene ligands by DFT. Issue 9 (9th June 2020)

• Record Type: Journal Article
• Authors: Ayoubi‐Chianeh, Mojgan; Kassaee, Mohamad Z.
• Is Part Of: Journal of the Chinese Chemical Society. Volume 67:Issue 9(2020)
• Page Start: 1544
• Page End: 1551
• Publication Date: 2020-06-09
• Subjects: bidentate -- DFT -- ligand -- monodentate -- rhodium -- silylene; Chemistry -- Periodicals; Electronic journals; 540.5
• DOI: 10.1002/jccs.202000113
• Languages: English
• ISSNs: 0009-4536

Abstract

Abstract: Considering the importance of silylene ligands in transition metal‐mediated catalytic reactions, we have scrutinized eight novel monodentate (1 –4 ) and bidentate (1 ′ ‐4 ′ ) derivatives of 2, 5‐diX‐cyclopentasilylene‐2, 4‐dienes (X = NH2, OH, PH2, and SH), at M06/6‐311++G** level of theory. To probe the complexation ability of our scrutinized silylene ligands with Rh atom (1 Rh ‐4 Rh and 1 ′ Rh ‐4 ′ Rh, respectively), thermodynamic and structural parameters such as complexation energy (Δ E Com ), singlet‐triplet energy gap (Δ E s‐t ), bond length, along with NBO and atoms in molecules analyses are provided. In going from less electron donating groups (EDGs) to more EDGs (NH2 > OH > PH2 > SH), the σ ‐donor strength and ligand flexibility increase. Structures 1 and 1 ′ turn out as the most nucleophilic species for showing the highest nucleophilicity ( N = 5.47 and 5.40 eV, respectively). Furthermore, they exhibit the highest proton affinity values (PA = 271.46 and 271.23 kcal/mol, respectively). The results indicate that bidentate coordination mode of silylene leads to a stronger Si‐Rh complex. The overall orders of σ ‐donation ability for monodentate and bidentate silylene ligands are 1 > 2 > 3 > 4 and 1 ′ > 2 ′ > 3 ′ > 4 ′, respectively. Abstract : We have scrutinized eight novel monodentate (1 ‐4 ) and bidentate (1 ′‐4 ′) derivatives of 2, 5‐diXcyclopentasilylene‐2, 4‐dienes (X = NH2, OH, PH2, and SH), and their corresponding complexes with Rh atom (1Rh ‐4Rh and 1 ′Rh ‐4 ′Rh, respectively), at M06/6‐311++G** level of theory. The overall orders of sigma donation ability of monodentate and bidentate ligands are 1 > 2 > 3 > 4 and 1 ′ > 2 ′ >3 ′ > 4 ′, respectively.