Synthesis and Crystal Structures of Methyl 3-(Benzoylamino)-6-methyl-2-oxo-2H-pyran-5-carboxylate and N-[5-(3,4-Dimethoxyphenyl)-6-methyl-2-oxo-2H-pyran-3-yl]benzamide

• Published in: Journal of chemical crystallography 2012-05, Vol.42 (5), p.443-449
• Main Authors: Kranjc, Krištof, Juranovič, Amadej, Kočevar, Marijan, Perdih, Franc
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Crystallography and Scattering Methods; Inorganic Chemistry; Organometallic Chemistry; Original Paper; Physical Chemistry
• ISSN: 1074-1542; 1572-8854
• DOI: 10.1007/s10870-011-0266-5

The compounds methyl 3-(benzoylamino)-6-methyl-2-oxo-2 H -pyran-5-carboxylate ( 1 ), C 15 H 13 NO 5 , and N -[5-(3,4-dimethoxyphenyl)-6-methyl-2-oxo-2 H -pyran-3-yl]benzamide ( 2 ), C 21 H 19 NO 5 , crystallize as a centrosymmetric hydrogen-bonded dimer facilitated by N–H···O interactions involving the amide and carbonyl moiety of the lactone group of adjacent molecules. Supramolecular aggregation in 1 is controlled by a combination of π–π interactions [centroid–centroid distance = 4.0745(11) Å] and weak C–H···O hydrogen bonding between the phenyl ring of the benzoylamino group and the carbonyl atom of the methoxycarbonyl group and in 2 by a combination of π–π interactions [centroid–centroid distance = 4.0699(8) and 4.1556(10) Å], weak C–H···O interactions between the methoxy substituents of the adjacent dimethoxyphenyl group and weak C–H··· π interactions. Graphical Abstract 2 H -Pyran-2-ones represent an important class of compounds useful for various ring transformations, the titled compounds crystallize as a centrosymmetric hydrogen-bonded dimers.