Crystal Structure Determination and Hydrogen-Bonding Patterns in 2-Pyridinecarboxamide

Gerzon E Delgado,Asiloé J Mora,Jines E Contreras,Jeans W Ramírez,Marilia Guillén-Guillén

doi:10.4236/csta.2012.13006

Abstract

The title compound, 2-pyridinecarboxamide, C6H6N2O, crystallize in the monoclinic system with space group P21/n (No14), Z = 4, and unit cell parameters a = 5.2074(1) , b = 7.1004(1) , c = 16.2531(3) , = 100.260(1)o. The crystal structure of the title compound, was reported previously from Weissenberg photographic data with R = 0.127. It has now been redetermined, providing a significant increase in the precision of the derived geometric parameters. The crystal packing is governed by N--HO hydrogen bond-type intermolecular interactions, forming infinite one-dimensional chains with graph-set notation C(4), R22(8) and R24(8).

Highlights

The three isomers of pyridinecarboxamide; 2-pyridine carboxamide or picolinamide, 3-pyridinecarboxamide or nicotinamide and 4-pyridinecarboxamide or isonicotinamide are a class of medicinal agents which can be classified as GRAS compounds
The present paper reports a redetermination of the crystal structure of 2-pyridinecarboxamide, with greater precision and accuracy
The dihedral angle formed between the pyridine ring and the amide plane is 18.26(9) ̊. This value is similar with the observed in the other picolinamide cations EYIXAL, FUGDER and POVZEF, but higher that 6.4(2) Å observed in the neutral molecule of co-crystal EXAPEZ

Summary

Introduction

The three isomers of pyridinecarboxamide; 2-pyridine carboxamide or picolinamide, 3-pyridinecarboxamide or nicotinamide and 4-pyridinecarboxamide or isonicotinamide are a class of medicinal agents which can be classified as GRAS (generally regarded as safe) compounds. A second hydrogen bond acceptor is the lone pair on the N atom of the pyridine ring. This makes these molecules very versatile for a variety of hydrogen bonded interactions, especially in pharmaceutical co-crystals [2,3,4,5,6,7,8,9,10,11,12,13]. The present paper reports a redetermination of the crystal structure of 2-pyridinecarboxamide (picolinamide), with greater precision and accuracy. An analysis of the hydrogen-bonding patterns is included

Crystallization of the Title Compound

FT-IR and NMR Analysis

X-Ray Powder Diffraction

Results and Discussion