Syntheses, Weak Interactions, and Crystal Structures of Two Tetrabromocuprate(II) Complexes Containing Benzyl Substituted Alkyl Pyridinium

Abstract

Two tetrabromocuprate(II) complexes containing substituted benzyl alkyl pyridinium, [Bz-4-MePy]2[CuBr4] (1) and [Bz-4-EtPy]2[CuBr4] (2) ([Bz-4MePy]+ = (1-benzyl-4′-methylpyridinium) [Bz-4-EtPy]+ = 1-benzyl-4′-ethylpyridinium), were crystallized from methanol and dilute HBr solutions, and were determined by single crystal X-ray diffraction. Two complexes crystallize in the orthorhombic system with space group Pna21, and comprise two tortuous cations and one tetrahedral [CuBr4]2– anion. The [CuBr4]2– anions in two complexes form a linear chain by Br···Br interaction with the distance of 4.001 Å for 1 and 4.062 Å for 2, while the combination of C‒H···Br and C‒H···N weak hydrogen bonds, p···π and π···π, interactions consolidate the crystal packing and results in a 3D network structure.