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Updated: Jun 1, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
1,3-Bis(4-methyl-benz-yl)pyrimidine-2,4(1H,3H)-dione
Gong-Chun Li1, Xiao-Ping Song, Li-Ke Zhang
1College of Chemistry and Chemical Engineering, Xuchang University, Xuchang, Henan Province 461000, People's Republic of China.
Abstract:
In the title mol-ecule, C(20)H(20)N(2)O(2), the central pyrimidine ring forms dihedral angles of 71.9 (1) and 69.8 (1)° with the two benzene rings. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link mol-ecules into centrosymmetric dimers. The crystal packing exhibits also π-π inter-actions as indicated by short distances of 3.674 (2) Å between the centroids of the pyrimidine rings of neighbouring mol-ecules.
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