How Do Aromatic Nitro Compounds React with Nucleophiles? Theoretical Description Using Aromaticity, Nucleophilicity and Electrophilicity Indices

Abstract

In this study, we present a complete description of the addition of a model nucleophile to the nitroaromatic ring in positions occupied either by hydrogen (the first step of the SNAr-H reaction) or a leaving group (SNAr-X reaction) using theoretical parameters including aromaticity (HOMA), electrophilicity and nucleophilicity indices. It was shown both experimentally and by our calculations, including kinetic isotope effect modeling, that the addition of a nucleophile to the electron-deficient aromatic ring is the rate limiting step of both SNAr-X and SNAr-H reactions when the fast transformation of σH-adduct into the products is possible due to the specific reaction conditions, so this is the most important step of the entire reaction. The results described in this paper are helpful for better understanding of the subtle factors controlling the reaction direction and rate.

Non-Covalent Forces in Naphthazarin—Cooperativity or Competition in the Light of Theoretical Approaches

“…It is a quantitative evidence of the intramolecular features reorganization associated with the presence of cooperativity of the non-covalent intramolecular interactions. We have applied the Fukui functions [ 58 , 59 ] to follow the electrophilicity and nucleophilicity changes related to the bridged proton position on the one site of the molecule from global minimum (Min_1) to the intermediate structure (Min_2). The atoms involved in the quasi-rings formation were taken into consideration as showed in Figure 5 .…”

A Simple, Transition Metal Catalyst‐Free Method for the Design of Complex Organic Building Blocks Used to Construct Porous Metal–Organic Frameworks

“…These materials feature high stability and offer outstanding gas separation and storage properties [56] . In theory, a single electron‐withdrawing group on a benzene ring can activate three positions, namely two ortho ‐ and one para ‐, for S N Ar reactions [57] . Thus, it was hypothesized that using trifluorobenzene that contains a strong electron‐withdrawing group, such as nitro, would lead to the desired piperazine intermediates necessary for the subsequent synthesis of tri‐ and hexacarboxylate ligands.…”

“…[56] In theory, a single electron-withdrawing group on a benzene ring can activate three positions, namely two ortho-and one para-, for S N Ar reactions. [57] Thus, it was hypothesized that using trifluorobenzene that contains a strong electron-withdrawing group,…”

A Simple, Transition Metal Catalyst‐Free Method for the Design of Complex Organic Building Blocks Used to Construct Porous Metal–Organic Frameworks

“…[56] In theory, a single electron-withdrawing group on a benzene ring can activate three positions, namely two ortho-and one para-, for S N Ar reactions. [57] Thus, it was hypothesized that using trifluorobenzene that contains a strong electron-withdrawing group, such as nitro, would lead to the desired piperazine intermediates necessary for the subsequent synthesis of triand hexacarboxylate ligands. To start, piperazine-carboxylate precursors were first synthesized (Scheme 5) from the corresponding commercially available aromatic amines [58] to obtain the known 4-pip-CO 2 Et•HCl [59] and the new 5-pip-diCO 2 Me•HCl (Section S3.8).…”