Introduction

Pihko, Petri M.

doi:10.1002/9783527627844.ch1

Cited by 42 publications

(47 citation statements)

References 17 publications

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“…[8] Most research focuses on the direct activation of neutral substrates by hydrogen bonding while recent studies take advantage of the anion binding of ion-pairing intermediates. [9] Inspired by the strategies developed in organocatalysis [10–12] and our previous research on the Rh/bisphosphine catalyzed asymmetric hydrogenation of nitroalkenes assisted by thiourea, [13] we sought to extend anion-binding catalysis to the transition metal-catalyzed asymmetric hydrogenation.…”

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confidence: 99%

Rhodium‐Catalyzed Asymmetric Hydrogenation of Unprotected NH Imines Assisted by a Thiourea

et al. 2014

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Asymmetric hydrogenation of unprotected N-H imines catalyzed by Rh/bisphosphine-thiourea provided chiral amines with up to 97% yield and 95% ee. 1H NMR studies, coupled with control experiments, implied that catalytic chloride-bound intermediates were involved in the mechanism via the dual hydrogen-bonding interaction. Deuteration experiments proved that the hydrogenation proceeded through a pathway consistent with the imine.

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confidence: 99%

Rhodium‐Catalyzed Asymmetric Hydrogenation of Unprotected NH Imines Assisted by a Thiourea

et al. 2014

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“…In the case of noncovalent interactions between the substrate and the catalyst, the activation of the substrate occurs via weak binding exemplified by hydrogen bonding [6] or ionic interaction as in the case of phase transfer catalysis [7]. …”

Section: Introductionmentioning

confidence: 99%

Asymmetric Organocatalysis at the Service of Medicinal Chemistry

Ricci

2014

ISRN Organic Chemistry

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The application of the most representative and up-to-date examples of homogeneous asymmetric organocatalysis to the synthesis of molecules of interest in medicinal chemistry is reported. The use of different types of organocatalysts operative via noncovalent and covalent interactions is critically reviewed and the possibility of running some of these reactions on large or industrial scale is described. A comparison between the organo- and metal-catalysed methodologies is offered in several cases, thus highlighting the merits and drawbacks of these two complementary approaches to the obtainment of very popular on market drugs or of related key scaffolds.

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“…However, the distances between most water molecules are about 2 Å (figure 4). This value corresponds to the hydrogen bond distance between the water molecules 1.9 Å [18]. Thus, due to a greater adsorbate-adsorbate interaction energy as compared to the adsorbateadsorbent energy (E HB (OH· · · ) = 7.5 kJ/mol [19] vs. E HB (OH· · · O) = 13-30 kJ/mol [18,[20][21][22]), a hydrogen-bonded network of water molecules is formed and, as a consequence, there takes place a formation of a film on the surface.…”

Section: Process Modeling Of Physical Adsorption Of Water and Methanementioning

confidence: 99%

“…This value corresponds to the hydrogen bond distance between the water molecules 1.9 Å [18]. Thus, due to a greater adsorbate-adsorbate interaction energy as compared to the adsorbateadsorbent energy (E HB (OH· · · ) = 7.5 kJ/mol [19] vs. E HB (OH· · · O) = 13-30 kJ/mol [18,[20][21][22]), a hydrogen-bonded network of water molecules is formed and, as a consequence, there takes place a formation of a film on the surface. This well agrees with the already known experimental data [23]: the adsorption energy values of isolated water molecules are much less than the experimental values; in the monolayer on the graphite surface there exists a flat pack of associated molecules at the experiment temperature 293 K.…”

Section: Process Modeling Of Physical Adsorption Of Water and Methanementioning

confidence: 99%

Modeling Adsorption–Desorption Processes at the Intermolecular Interactions Level

Varfolomeeva

Terent’ev

2018

IOP Conf. Ser.: Mater. Sci. Eng.

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Abstract.Modeling of the surface adsorption and desorption processes, as well as the diffusion, are of considerable interest for the physical phenomenon under study in ground tests conditions. When imitating physical processes and phenomena, it is important to choose the correct parameters to describe the adsorption of gases and the formation of films on the structural materials surface. In the present research the adsorption-desorption processes on the gas-solid interface are modeled with allowance for diffusion. Approaches are proposed to describe the adsorbate distribution on the solid body surface at the intermolecular interactions level. The potentials of the intermolecular interaction of water-water, water-methane and methanemethane were used to adequately modeling the real physical and chemical processes. The energies calculated by the B3LYP/aug-cc-pVDZ method. Computational algorithms for determining the average molecule area in a dense monolayer, are considered here. Differences in modeling approaches are also given: that of the proposed in this work and the previously approved probabilistic cellular automaton (PCA) method. It has been shown that the main difference is due to certain limitations of the PCA method. The importance of accounting the intermolecular interactions via hydrogen bonding has been indicated. Further development of the adsorption-desorption processes modeling will allow to find the conditions for of surface processes regulation by means of quantity adsorbed molecules control. The proposed approach to representing the molecular system significantly shortens the calculation time in comparison with the use of atom-atom potentials. In the future, this will allow to modeling the multilayer adsorption at a reasonable computational cost.

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Introduction

Cited by 42 publications

References 17 publications

Rhodium‐Catalyzed Asymmetric Hydrogenation of Unprotected NH Imines Assisted by a Thiourea

Rhodium‐Catalyzed Asymmetric Hydrogenation of Unprotected NH Imines Assisted by a Thiourea

Asymmetric Organocatalysis at the Service of Medicinal Chemistry

Modeling Adsorption–Desorption Processes at the Intermolecular Interactions Level

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