A New Polymorphic Form of Maltol: Crystallization and Structure Refinement

• Published in: Crystal research and technology (1979) Vol. 59; no. 8
• Main Authors: Srinivasan, Kavipriya, Karuppannan, Srinivasan
• Format: Journal Article
• Language: English
• Published: 01-08-2024
• Subjects: hirshfeld surfaces; maltol; polymorphism; scxrd; solution crystallization
• ISSN: 0232-1300; 1521-4079
• DOI: 10.1002/crat.202300336

A new polymorph of maltol, a food and intermediate pharmaceutical material, is discovered through solution crystallization process using a mixed solvent of water and ethanol with l‐menthol as an additive. It belongs to monoclinic crystal system with lattice parameters: a = 7.136(8) Å, b = 24.23(3) Å, c = 7.020(8) Å, and β = 106.22(3)°, volume =  1165 (2) Å3 and the refinement factor is R = 6.64%. With single crystal X‐ray diffraction (SCXRD) data as input, the intermolecular interactions between the new polymorph of maltol is investigated through Hirshfeld surface analysis, the higher percentage of overall interaction between the polymorph (H…H) interaction, and the (O…H) interaction contributes more to the generation of new polymorph. The 2D finger print plot depicts the interactions are mainly due to the hydrogen bonds.
A new polymorphic form of maltol is discovered in the presence of an additive l‐menthol, from the mixed solvents (water‐ ethanol) through solution crystallization process.