Synthesis and structure of push-pull merocyanines based on barbituric and thio-barbituric acid

Georgii Bogdanov; John P Tillotson; Jenna Bustos; Tatiana V Timofeeva

doi:10.1107/S2056989019011071

Synthesis and structure of push-pull merocyanines based on barbituric and thio-barbituric acid

Acta Crystallogr E Crystallogr Commun. 2019 Aug 16;75(Pt 9):1306-1310. doi: 10.1107/S2056989019011071. eCollection 2019 Sep 1.

Authors

Georgii Bogdanov¹, John P Tillotson², Jenna Bustos¹, Tatiana V Timofeeva¹

Affiliations

¹ Department of Chemistry, New Mexico Highlands University, Las Vegas, New Mexico, 87701, USA.
² School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, 30332, USA.

Abstract

Two compounds, 1,3-diethyl-5-{(2E,4E)-6-[(E)-1,3,3-tri-methyl-indolin-2-yl-idene]hexa-2,4-dien-1-yl-idene}pyrimidine-2,4,6(1H,3H,5H)-trione or TMI, C₂₅H₂₉N₃O₃, and 1,3-diethyl-2-sulfanyl-idene-5-[2-(1,3,3-tri-methyl-indolin-2-yl-idene)ethyl-idene]di-hydro-pyrimidine-4,6(1H,5H)-dione or DTB, C₂₁H₂₅N₃O₂S, have been crystallized and studied. These compounds contain the same indole derivative donor group and differ in their acceptor groups (in TMI it contains oxygen in the para position, and in DTB sulfur) and the length of the π-bridge. In both materials, mol-ecules are packed in a herringbone manner with differences in the twist and fold angles. In both structures, the mol-ecules are connected by weak C-H⋯O and/or C-H⋯S bonds.

Keywords: barbituric acid derivatives; crystal structure; push–pull chromophores.

Grants and funding

This work was funded by National Science Foundation grant DMR-1523611.