Co-crystals of caffeine and hydroxy-2-naphthoic acids: unusual formation of the carboxylic acid dimer in the presence of a heterosynthon.
A group of caffeine-containing co-crystals of hydroxy-2-naphthoic acids were synthesized and analyzed via single-crystal X-ray diffraction and IR analysis. The imidazole-carboxylic acid synthon was observed in co-crystals involving 1-hydroxy-2-naphthoic and 3-hydroxy-2-naphthoic acid. In the case of 6-hydroxy-2-naphthoic acid, the co-crystal exhibits a hydrogen-bonded carboxylic acid dimer in the presence of a hydroxyl-caffeine heterosynthon.
Bucar
Dejan-Kresimir
DK
Solid State Sciences, Global Pharmaceutical R&D, Abbott Laboratories, North Chicago, Illinois 60064, USA.
Henry
Rodger F
RF
Lou
Xiaochun
X
Duerst
Richard W
RW
Borchardt
Thomas B
TB
MacGillivray
Leonard R
LR
Zhang
Geoff G Z
GG
D002110:Caffeine / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry; D003460:Crystallization; D018360:Crystallography, X-Ray; D019281:Dimerization; D006860:Hydrogen Bonding; D008958:Models, Molecular; D015394:Molecular Structure; D009284:Naphthols / Q000737:chemistry*; D033362:Powder Diffraction; D017550:Spectroscopy, Fourier Transform Infrared
D002264:Carboxylic Acids; D009284:Naphthols; D002110:Caffeine