Impact of molecular and crystal structure on the melting points in halo-substituted phenyl-quinazolinones

Đilović, Ivica (avtor), Judaš, Nenad (avtor), Komar, Mario (avtor), Molnar, Maja (avtor), Počkaj, Marta (avtor), Balić, Tomislav (avtor)

Three halo-substituted phenyl-quinazolinone derivatives were prepared and structurally characterized [1 = 3-(4-chlorophenyl)-6-iodo-2-methylquinazolin-4(3H)-one, 2 = 6-iodo-3-(4-methoxyphenyl)-2-methylquinazolin-4(3H)-one, and 3 = 7-chloro-2-methyl-3-[4-(trifluoromethoxy)phenyl]quinazolin-4(3H)-one)] in order to explore the relationship between structure and melting point in this group of compounds. Depending on the compound, molecules are interconnected by weak π∙∙∙π interactions, have I···Cl or Cl···Cl halogen bonding, or primarily form C–H∙∙∙N, C–H∙∙∙O, and π∙∙∙π interactions (no halogen bonding). The presence of the OCF$_3$ group leads to interactions between fluorine atoms that are shorter than the sum of the van der Waals radius for fluorine, suggesting that these interactions contribute to the overall lattice energy. The sequence of melting points cannot be fully explained by intermolecular interactions present in the solid state (enthalpy factor). To address this, a concept related to entropy called the functional group rotation influence, which relates to a decrease in fusion entropy caused by the rotational freedom of polyatomic groups, was introduced. Analysis of previously synthesized 3-phenylquinazolinones showed that the compounds with the highest melting point are the quinazoline-substituted and phenyl-nitro-substituted ones. Among halo-phenyl-substituted compounds, the melting point follows the sequence ortho < meta < para. Regarding the halogen atom type, the order of melting points is Cl ≈ Br > F > I for enantiopure and Br > I ≈ Cl > F for racemic compounds. Also, the melting point order correlates to halogen bond energy (I > Br > Cl > F) only when the geometry and energy of these interactions are favorable.

• Jezik: Angleški jezik
• Ključne besede: phenyl-quinazolinones, halogen bond interactions, melting point, functional group rotation influence
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FKKT - Fakulteta za kemijo in kemijsko tehnologijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2025
• Št. strani: 19 str.
• Številčenje: Vol. 15, iss. 1, art. 39
• PID: 20.500.12556/RUL-166768
• UDK: 544.1:547.856
• ISSN pri članku: 2073-4352
• DOI: 10.3390/cryst15010039
• COBISS.SI-ID: 221536003
• Datum objave v RUL: 24.01.2025

Gradivo je del revije

• Naslov: Crystals
• Skrajšan naslov: Crystals
• Založnik: MDPI
• ISSN: 2073-4352
• COBISS.SI-ID: 36677893

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: fenil-kinazolinoni, halogenske vezi, tališče, vpliv rotacije funkcionalne skupine