nonclassical noncovalent interactions control: A case study of the crystal structure of 3,5-dibromo-2-amino-4,6-dimethylpyridinium tetrahalocuprate [3,5-DBr-2-A-4,6-DMPH]₂CuX₄ (X=Cl, and Br)

• Published in: Journal of molecular structure Vol. 985; no. 1; pp. 27 - 33
• Main Authors: AlDamen, Murad A, Haddad, Salim F
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2011
• Subjects: bromine; case studies; crystal structure; salts; X-ray diffraction
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2010.09.052

The compound [3,5-dibromo-2-amino-4,6-dimethylpyridinium]₂CuCl₄, (1), was prepared from acidic hydrochloric acetonitrilic medium containing CuCl₂ and 3,5-dibromo-2-amino-4,6-dimethylpyridinium bromide while [3,5-dibromo-2-amino-4,6-dimethylpyridinium]₂CuBr₄, (2), from acidic HBr/Br₂ ethanolic medium containing 4,6-dimethylpyridine and CuBr₂. The ring got dibrominated at 3 and 5 positions in situ. Single-crystal X-ray diffraction proved the compounds to be isomorphous in P−1. A systematic study of the crystallographic parameters in dibrominated and nonbrominated 2-amino-4,6-dimethylpyridine salts will explain the role of nonclassical noncovalent interaction between aryl bromine and ionic metal bromide in the control of structure.