Lm. Toledo et al., DESIGN OF MOLECULAR-SOLIDS - APPLICATION OF 2-AMINI-4(1H)-PYRIDONES TO THE PREPARATION OF HYDROGEN-BONDED ALPHA-NETWORKS AND BETA-NETWORKS, Chemistry of materials, 6(8), 1994, pp. 1222-1226
Crystallographic studies have demonstrated 2-amino-4(1H)-pyridones to
be effective analogs of ureas for the design of molecular solids. This
ring system is capable of producing persistent hydrogen-bonded alpha-
networks with a molecular repeat distance of 6.7 angstrom compared to
4.7 angstrom for urea. The addition at C-5 of nitrile function to the
2-amino-4(1H)-pyridone ring system was sufficient to form a second alp
ha-network using the syn hydrogen of the NH2 group. The presence of tw
o a-network-forming functionalities in the same molecule resulted in a
beta-network ultimately producing a layered molecular crystal.