A solid solution of ethyl and d3-methyl 2-[(4-methylpyridin-2-yl)amino]-4-(pyridin-2-yl)thiazole-5-carboxylate

Abstract

The synthesis of ethyl 2-[(4-methylpyridin-2-yl)amino)-4-(pyridin-2-yl)thiazole- 5-carboxylate via the Hantzsch reaction and partial in situ transesterification during recrystallization from methanol-d4 to the d3-methyl ester, resulting in the title solid solution, ethyl 2-[(4-methylpyridin-2-yl)amino)-4-(pyridin-2-yl)thiazole-5-carboxylate–d3-methyl 2-[(4-methylpyridin-2-yl)amino)-4-(pyridin-2-yl)thiazole-5-carboxylate (0.88/0.12), 0.88C17H16N4O2S·0.12C16D3H11N4O2S, is reported. The refined ratio of ethyl to d3-methyl ester in the crystal is 0.880 (6):0.120 (6). The pyridine ring is significantly twisted out of the plane of the approximately planar picoline thiazole ester moiety. N—H...N hydrogen bonds between the secondary amino group and the pyridine nitrogen atom of an adjacent symmetry-related molecule link the molecules into polymeric hydrogen-bonded zigzag tapes extending by glide symmetry in the [001] direction. There is structural evidence for intramolecular N...S chalcogen bonding and intermolecular weak C—H...O hydrogen bonds between adjacent zigzag tapes.

Keywords

• 2-aminothiazole
• hantzsch reaction
• heterocycle
• solid solution
• hydrogen bonding
• crystal structure