Conversion of diarylchalcones into 4,5-dihydropyrazole-1-carbothioamides: molecular and supramolecular structures of two precursors and three products

Acta Crystallographica Section E: Crystallographic Communications

Ravindranath S. Rathore¹  Asma²  Nagaraja Manju²  Balakrishna Kalluraya²  Hemmige S. Yathirajan³  Mohammed A. E. Shaibah³  Christopher Glidewell⁴ 

[1] Department of Bioinformatics, School of Earth, Biological and Environmental Sciences, Central University of South Bihar, Gaya-824236, India;Department of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore-574 199, India;Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysuru-570 006, India;School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, UK;

关键词: synthesis;    cyclocondensation;    chalcones;    heterocyclic compounds;    reduced pyrazoles;    crystal structures;    molecular conformation;    hydrogen bonding;    supramolecular assembly;   

DOI  :  10.1107/S2056989020001735

来源: DOAJ

【 摘 要 】

Chalcones of type 4-XC6H4C(O)CH=CHC6H4(OCH2CCH)-4, where X = Cl, Br or MeO, have been converted to the corresponding 4,5-dihydropyrazole-1-carbothioamides using a cyclocondensation reaction with thiosemicarbazide. The chalcones 1-(4-chlorophenyl)-3-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C18H13ClO2, (I), and 1-(4-bromophenyl)-3-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C18H13BrO2, (II), are isomorphous, and their molecules are linked into sheets by two independent C—H...π(arene) interactions, both involving the same aryl ring with one C—H donor approaching each face. In each of the products (RS)-3-(4-chlorophenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C19H16ClN3OS, (IV), (RS)-3-(4-bromophenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C19H16BrN3OS, (V), and (RS)-3-(4-methoxyphenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C20H19N3O2S, (VI), the reduced pyrazole ring adopts an envelope conformation with the C atom bearing the 4-prop-2-ynyloxy)phenyl substituent, which occupies the axial site, displaced from the plane of the four ring atoms. Compounds (IV) and (V) are isomorphous and their molecules are linked into chains of edge-fused rings by a combination of N—H...S and C—H...S hydrogen bonds. The molecules of (VI) are linked into sheets by a combination of N—H...S, N—H...N and C—H...π(arene) hydrogen bonds. Comparisons are made with the structures of some related compounds.

【 授权许可】

Unknown