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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Crystal structure, hydrogen bonding and Hirshfeld surface analysis of 2-amino-4-meth-oxy-6-methyl-pyrimidinium
Muthaiah Jeevaraj1, Palaniyappan Sivajeyanthi1, Bellarmin Edison1
1Department of Chemistry, Government Arts College (Autonomous), Thanthonimalai, Karur 639 005, Tamil Nadu, India.
Abstract:
In the crystal structure of the title salt, C6H10N3O+·C7H4ClO2-, the dihedral angle between the pyrimidine ring of the 2-amino-4-meth-oxy-6-methyl-pyrimidine cation and the the benzene ring of the 2-chloro-benzoate anion is 2.2 (1)°. In the anion, the benzene ring forms a dihedral angle of 8.5 (2)° with the carboxyl group. The pyrimidine N atom of the cation is protonated and the meth-oxy substituent is essentially coplanar with the parent ring. The protonated N atom and the N atom of the 2-amino group are hydrogen bonded to the 4-chloro-benzoate anion through a pair of N-H⋯Ocarbox-yl hydrogen bonds, forming an R22(8) ring motif linked through a centrosymmetric R24(8) ring motif, resulting in a pseudo-tetra-meric DDAA array. These units are linked through inter-molecular meth-oxy C-H⋯Cl hydrogen bonds into ribbon-like chains extending along the c-axis direction. The crystal structure also features π-π stacking inter-actions between the rings in the cation and anion [minimum ring centroid separation = 3.7707 (12) Å].
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