Understanding the crystalline formation of triazene<i>N</i>-oxides and the role of halogen⋯π interactions

Martins, Marcos A. P.; Salbego, Paulo R. S.; Moraes, Guilherme Alves de; Bender, Caroline R.; Zambiazi, Priscilla J.; Orlando, Tainára; Pagliari, Anderson B.; Frizzo, Clarissa P.; Hörner, Manfredo

doi:10.1039/c7ce02015e

Cited by 33 publications

(96 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The supramolecular cluster demarcation,, , which considers the contact area and stabilization energies between molecules, was used to obtain information on the crystalline structure. A schematic representation of the supramolecular cluster is shown in Figure , which qualitatively demonstrates how information was obtained.…”

Section: Resultsmentioning

confidence: 99%

“…The sum of the set of MN molecules is called molecular coordination number (MCN). From this point and for clarity purposes, the number of neighboring molecules from the MCN are named N. It is worth noting that this methodology does not neglect any molecules/interactions that may contribute to crystal formation . The supramolecular cluster of each molecule was built and the contact area and stabilization energy data were obtained (see SI, Figures S3–S16, and Tables S3–S16).…”

Section: Resultsmentioning

confidence: 99%

“…It was proposed crystallization mechanisms using a retrocrystallization process, which uses formed crystal data to presume how the stages of crystallization process occurred. Some investigations reported by our research group proposed crystallization mechanisms for a series of isoxazoles, triazenes N ‐oxides, substituted pyrazoles, N ‐phenilamides, and polymorph of [2]rotaxane …”

Section: Resultsmentioning

confidence: 99%

“…Crystallization consists of a stepwise process in which there is progressive growth with a gradually increasing complexity , . It can be considered a process analogous to the Darwinian evolutionary process .…”

Section: Resultsmentioning

confidence: 99%

“…Additionally, stage parameters (NG/NC and N CG %) calculated from the normalized data were used for better comprehension of the involved crystallization steps. The NG/NC indicates the factor that rules each step.…”

Section: Resultsmentioning

confidence: 99%

See 4 more Smart Citations

Crystallization Mechanisms Applied to Understand the Crystal Formation of Rotaxanes

et al. 2019

Self Cite

View full text Add to dashboard Cite

The present study discusses the crystalline packing formation of several [2]rotaxanes with Leigh‐type tetralactam macrocycle bearing different threads. The presence of solvent molecules in some structures are also addressed to shed some light on this matter. Additionally, the degree of similarity between supramolecular structures of rotaxanes was discussed using similarity indices. For this, new descriptors and crystallization mechanisms, which were proposed in terms of contact area and stabilization energy, were carried out to evaluate the rotaxane molecules. It was possible to observe similar general stages of crystallization dominated by the formation of 1D‐blocks and, in fewer cases, by dimers in the first stage of nucleation. The preference for the formation of 1D nuclei resides in the large contact area and complementarity involved in the large set of interactions between the rotaxanes at the earliest stages of crystallization. In this context, it was possible to propose when solvent molecules are trapped between the rotaxanes during crystal formation. Therefore, a unique example of a rotaxane whose topology favored the entrapment of water molecules between rotaxanes during the first stage of the crystallization process is presented. Crystallization mechanisms showed to be a valuable asset in the supramolecular investigation of rotaxanes in the crystalline state.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 3 more Smart Citations

Crystallization Mechanisms Applied to Understand the Crystal Formation of Rotaxanes

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

[2]Rotaxanes Bearing a Tetralactam Macrocycle: The Role of a Trifurcated Hydrogen Bond in the Crystalline State

et al. 2019

Self Cite

View full text Add to dashboard Cite

This study investigated the proper classification and quantification of intercomponent trifurcated hydrogen bonds, in the crystalline state, of rotaxanes bearing a tetralactam Leigh‐type macrocycle. Quantum mechanical calculations were carried out to obtain the interaction paths and their stabilization energies. In general, the use and necessity of fragmentation in types of interaction have been reported in the literature, although they are commonly performed only using a geometric approach. This results in N–H···O interactions that are indicated as the main interactions between components, neglecting other possible interactions. The use of energetic fragmentation was demonstrated here under an appropriate demarcation considering all interactions and showing the existence and role of the C–H···O interaction. The C–H···O interactions showed similar energy to N–H···O interactions with average values around –4.75 kcal mol–1 and –4.60 kcal mol–1, respectively. This revealed that the three hydrogen bonds are part of a cooperative set of interactions with a similar contribution. The trifurcated hydrogen bonds presented high contribution in the total intercomponent stabilization energy of the rotaxanes, with an average value of 51 % in the studied series.

show abstract

Energetic and Topological Supramolecular Study and Nucleation Mechanism Proposal of Halogenated Phenols

2022

View full text Add to dashboard Cite

In this work, an energetic and topological supramolecular study of 10 different halogenated phenols, X−C6H4−OH (X=F, Cl, Br and I) in the ortho, meta, and para positions was carried out, except for X=Br, in ortho‐ and meta‐X‐phenols. Most compounds have a molecular coordination number (MCN) of fourteen. All intermolecular interactions were classified, and the robustness was evaluated. Strong intermolecular interactions such as O−H⋅⋅⋅O and π⋅⋅⋅π contributed half the energy of the cluster, although interactions considered weak as C−H⋅⋅⋅X and C−H⋅⋅⋅π reached 40 % in energetic contribution, as they revealed a greater number of occurrences. Additionally, these theoretical data of energy were correlated with experimental data of melting point and packing density revealing a notable trend. In almost all cases evaluating the same position, the higher the density, the higher the melting point and the higher the stabilizing energy. Finally, nucleation proposals were suggested for all compounds and revealed that six compounds needed three stages, while four compounds needed only two stages to promote the growth of the supramolecular structure in three directions.

show abstract

Understanding the crystalline formation of triazeneN-oxides and the role of halogen⋯π interactions

Abstract: Normalized parameters are presented to assist the interpretation of crystal mechanisms of a series of triazene N1-oxides. The role of halogen⋯π interactions is discussed.

Cited by 33 publications

References 30 publications

Crystallization Mechanisms Applied to Understand the Crystal Formation of Rotaxanes

Crystallization Mechanisms Applied to Understand the Crystal Formation of Rotaxanes

[2]Rotaxanes Bearing a Tetralactam Macrocycle: The Role of a Trifurcated Hydrogen Bond in the Crystalline State

Energetic and Topological Supramolecular Study and Nucleation Mechanism Proposal of Halogenated Phenols

Contact Info

Product

Resources

About