Fluorinated vs Nonfluorinated PR₂(biaryl) Ligands and Their [AuCl(L)] Complexes: Synthesis, X-ray Structures, and Computational Study of Weak Interactions. Bond, No Bond, and Beyond

Abstract

have been prepared. Their [AuCl(L n )] complexes and H congeners with PhJohnPhos or CyJohnPhos have been studied in order to examine the interactions that bring the distal aryl close to the Au−Cl bond region. X-ray, DFT structure optimization, QTAIM, and NCI methods allow for some understanding of the forces involved. The "no bond" noncovalent distal-aryl/Au−Cl weak interactions are produced at forced short distances achieved under intramolecular structural ligand pressure. Enhanced vdW distal-aryl/Au interactions at "no bond" distances shorter than the sum of Au and C vdW radii and weaker distal-aryl/Cl interactions at "no bond" distances beyond the sum of Cl and C vdW radii counterbalance the unfavorable structural distortion of the free ligand, providing some extra stability of the molecule on the order of 2−10 kcal mol −1 . The F substituents in the distal aryl induce shorter aryl distances to the Au−Cl zone, pointing overall to stronger π-aryl polarization as being mainly responsible for the NCIs with gold. The interactions in the C••• Cl zone, where the distances are larger than the sum of vdW radii, contribute only about 5%, according to energy estimations using NBOs.Article pubs.acs.org/IC

Gold(i) complexes bearing a PNP-type pincer ligand: photophysical properties and catalytic investigations

“…14 The gold-phosphorus and gold-chloride bond lengths are in the range of those reported previously for other gold–phosphine complexes. 7,14,15 Both P(1)–Au(1)–Cl(1) and P(2)–Au(2)–Cl(2) bond angles are close to the typical linear coordination. 15 The bromine complex, DPPMPY(AuBr) 2 , 2 , was obtained by treating a solution of 1 in CH 2 Cl 2 with an aqueous solution of potassium bromide (Scheme 2).…”

“…7,14,15 Both P(1)–Au(1)–Cl(1) and P(2)–Au(2)–Cl(2) bond angles are close to the typical linear coordination. 15 The bromine complex, DPPMPY(AuBr) 2 , 2 , was obtained by treating a solution of 1 in CH 2 Cl 2 with an aqueous solution of potassium bromide (Scheme 2). The NMR spectroscopic data of 2 were similar to those described above for 1 .…”

Expanding the Concepts Trans Influence and Back-Donation: Hybrid and Side Donations in [Cp*MIII(L)XY] (M = Rh, Ir) Complexes with CO, CN–, and CNR Ligands. A Window to Cis Influence

“…Concerning the CO group (and this holds for the CN and CNR groups also), it is so close to the Cp* π-electron cloud that direct side donation (not involving the metal orbitals) to the π* orbitals of the CO group might be significant, even if we expect that the contribution of these π(Cp*) → π*(CO) interactions must be lower than the classical π(M) → π*(CO) back-donation. Applying the strategy used for the study of biphenyl−gold noncovalent interactions in [AuCl-(PR 2 (biphenyl)] complexes, 20 we approach these and other electronic donations in the frame of density functional theory (DFT) on optimized molecular structures, in order to avoid the solid-state disturbances. We estimate the strength of the investigated interactions using natural bonding orbital (NBO) and second-order perturbation theory (SOPT) analyses.…”

Structural Diversity and Argentophilic Interactions in Small Phosphine Silver(I) Thiolate Clusters

“…Hence, we calculated the electron density distribution of the molecular units using DFT. This approach has proven useful in detailed analyses of the bonding scenario of metal complexes [53–58] . The QTAIM descriptors we used herein to characterize covalent and non‐covalent interactions are based on the electron density and energy densities at the bond critical points (bcp).…”