Bridging organometallics and quantum chemical topology: Understanding electronic relocalisation during palladium-catalyzed reductive elimination

Bifunctional squaramides with benzyl-like fragments: analysis of CH⋯π interactions by a multivariate linear regression model and quantum chemical topology

A multivariate linear regression model and quantum chemical topology are used for the quantitative description of non-covalent interactions in the transition state of the Michael addition catalyzed by bifunctional squaramides.

Deciphering the Curly Arrow Representation and Electron Flow for the 1,3-Dipolar Rearrangement between Acetonitrile Oxide and (1S,2R,4S)-2-Cyano-7-oxabicyclo[2.2.1]hept-5-en-2-yl Acetate Derivatives

This study is focused on describing the molecular mechanism beyond the molecular picture provided by the evolution of molecular orbitals, valence bond structures along the reaction progress, or conceptual density functional theory. Using bonding evolution theory (BET) analysis, we have deciphered the mechanism of the 1,3-dipolar rearrangement between acetonitrile oxide and (1S,2R,4S)-2-cyano-7-oxabicyclo[2.2.1]hept-5-en-2-yl acetate derivatives. The BET study revealed that the formation of the C-C bond takes place via a usual sharing model before the O-C one that is also formed in the halogenated species through a not very usual sharing model. The mechanism includes depopulation of the electron density at the N-C triple bond and creation of the V(N) and V(C) monosynaptic basins, depopulation of the former C-C double bond with the creation of V(C,C) basins, and final formation of the V(O,C) basin associated with the O-C bond. The topological changes along the reaction pathway take place in a highly synchronous way. BET provides a convenient quantitative method for deriving curly arrows and electron flow representation to unravel molecular mechanisms.

Ubiquity of cis-Halide → Isocyanide Direct Interligand Interaction in Organometallic Complexes

We recently reported a density functional theory (DFT) analysis of the Nb(V)-C bond in various NbCl₅(L) complexes, discovering that the carbon ligand L receives electronic density from the metal (classical back-donation) and from the chlorides in the cis position (direct interligand interaction). Here we report the synthesis and the structural characterization of two new coordination compounds of niobium pentahalides, i.e., NbX₅(CNXyl) (X = Cl, Br; Xyl = 2,6-C₆H₃Me₂), and the corresponding DFT analyses of the Nb(V)-C bond using the Natural Orbitals for Chemical Valence-Charge Displacement (NOCV-CD) approach, confirming the presence of a cis-halide → isocyanide direct interligand interaction. To verify whether the latter is limited to Nb complexes or not, we performed a NOCV-CD analysis on a series of several organometallic complexes based on Ti(IV), Nb(V), Ta(V), Rh(III), Pd(II), and Au(III), all of which bear one halide ligand and m-xylyl-isocyanide in a mutual cis position, revealing that the cis-halide → isocyanide interaction is always present.

Direct C–H heteroarylation by an acenaphthyl-based α-diimine palladium complex: improvement of the reaction efficiency for bi(hetero)aryls under aerobic conditions

A bulky ancenaphthyl skeleton-based α-diimine palladium complex has been developed, which exhibited high reactivity for direct heteroarylation of heteroaryl bromides under aerobic conditions with a broad substrate scope.

Design and application of a bifunctional organocatalyst guided by electron density topological analyses

Design of a catalyst via the identification of key interactions within the transition state with quantum chemical topology.

An explicit account of solvation is essential for modeling Suzuki–Miyaura coupling in protic solvents

We compared explicit and implicit solvation approaches in modeling the free energy profile of the final step of Suzuki–Miyaura coupling.