X-Ray Crystal Structure Determination of 5,6-Dibromonicotinic Acid and 5-Bromo,6-Chloronicotinic Acid

摘要

For some years a large series of new and closely related dihalonicotinic acids, dihalonicotinamides, and dihalopicolines have been in the process of synthesis in the Chemistry Department at the University of Arkansas at Little Rock. The study of such a series often affords new insights into the nature of matter. When it was observed that the three types of trisubstituted pyridines order themselves according to melting points, it was proposed that hydrogen bonding among molecules in the crystals of the acids and amides is an important intermolecular force which largely determines crystal structure. Proof of this can be obtained only by crystal structure determinations. Consequently, the structure determinations of 5,6-dibromonicotinic acid and 5-bromo-6-chloro-nicotinic acid were undertaken. (JES)