5-Trifluoromethoxy-substituted Nicotinic Acid, Nicotinamide and Related Compounds

Abstract

A practical and convenient method for synthesizing nicotinic acid and nicotinamide with the trifluoromethoxy group in position 5 of the ring has been developed. A series of related compounds, for example, nicotinic aldehyde and nicotinic alcohol, have been synthesized. It has been shown that 3-bromo-5-trifluoromethoxypyridine is a convenient and efficient synthon for palladium-catalyzed coupling reactions. The trifluoromethoxy group has been found to be remarkably stable against hydroiodic acid in contrast to the methoxy group.

Keywords

• nicotinic acid
• nicotinamide
• trifluoromethoxy group
• antimony trifluoride
• fluorination