Two polymorphs of N-(2-methoxyphenyl)-4-oxo-4H-chromone-3-carboxamide

• Type: Article in International Scientific Journal
• Date: 2013

Authors

gomes, ligia r. (Author) Other; low, john nicolson (Author) Other; borges, fernanda (Author) FCUP; cagide, fernando (Author) Other

Journal

Title: Acta Crystallographica Section C: Crystal Structure Communications

Vol. 69

Pages: 927-+

ISSN: 0108-2701

Publisher: Blackwell

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Scientific classification

FOS: Natural sciences > Chemical sciences

CORDIS: Physical sciences > Chemistry

Other information

Authenticus ID: P-006-8GN

DOI: 10.1107/S0108270113017538

Abstract (EN): The title compound, C17H13NO4, crystallizes in two polymorphic forms, each with two molecules in the asymmetric unit and in the monoclinic space group P2(1)/c. All of the molecules have intramolecular hydrogen bonds involving the amide group. The amide N atoms act as donors to the carbonyl group of the pyrone and also to the methoxy group of the benzene ring. The carbonyl O atom of the amide group acts as an acceptor of the beta and beta' C atoms belonging to the aromatic rings. These intramolecular hydrogen bonds have a profound effect on the molecular conformation. In one polymorph, the molecules in the asymmetric unit are linked to form dimers by weak C-H center dot center dot center dot O interactions. In the other, the molecules in the asymmetric unit are linked by a single weak C-H center dot center dot center dot O hydrogen bond. Two of these units are linked to form centrosymmetric tetramers by a second weak C-H center dot center dot center dot O interaction. Further interactions of this type link the molecules into chains, so forming a three-dimensional network. These interactions in both polymorphs are supplemented by pi-pi interactions between the chromone rings and between the chromone and methoxyphenyl rings.

Language: English

Type (Professor's evaluation): Scientific