2-Amino-3-carb-oxy-pyrazin-1-ium dihydrogen phosphate

Area of Science:

• Crystal engineering
• Supramolecular chemistry
• Hydrogen bonding

Background:

• Understanding the self-assembly of organic cations and inorganic anions is crucial in crystal engineering.
• Hydrogen bonds play a pivotal role in directing the formation of extended crystalline networks.
• The specific interactions within the title compound, C(5)H(6)N(3)O(2) (+)·H(2)PO(4) (-), were investigated.

Purpose of the Study:

• To elucidate the crystal structure of the title compound.
• To analyze the hydrogen bonding patterns and their role in network formation.
• To characterize the resulting supramolecular architecture.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the three-dimensional crystal structure.
• Analysis of hydrogen bond distances and angles was performed.
• Graph-set theory was utilized to describe the hydrogen bonding motifs.

Main Results:

• The crystal structure reveals dihydrogen phosphate anions linked by O-H⋯O hydrogen bonds into infinite double chains along the b axis.
• Cationic dimers, formed by N-H⋯O hydrogen bonds, bridge these chains, creating a 2D network parallel to the (100) plane.
• Various graph-set motifs (R(3)(3)(12), R(4)(3)(10), R(2)(2)(8), C(4)) were identified within the network.
• Weak C-H⋯O hydrogen bonds further connect these layers, resulting in a 3D supramolecular network.

Conclusions:

• The study successfully characterized the crystal structure and detailed the hydrogen bonding network.
• The formation of a complex 3D network is driven by a combination of O-H⋯O, N-H⋯O, and C-H⋯O hydrogen bonds.
• This work provides insights into the rational design of crystalline materials based on specific intermolecular interactions.