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Updated: May 7, 2026

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Improved synthesis of mono- and disubstituted 2-halonicotinonitriles from alkylidene malononitriles
Ashley R Longstreet1, Brian S Campbell, B Frank Gupton
1Department of Chemistry and Biochemistry, Florida State University , Tallahassee, Florida 32306, United States , and Department of Chemistry, Department of Chemical and Life Science Engineering, Virginia Commonwealth University , Richmond, Virginia 23284, United States.
Abstract:
Pyridines with 2,3,4 and/or 5 substitution remain challenging to prepare. Existing strategies to form multisubstituted 2-halonicotinonitriles via enamines suffer from dimerization of the starting alkylidene malononitriles resulting in low yields. Through alteration of reaction conditions, a new high yielding method into enamines was realized by condensing DMF-DMA and alkylidene malononitriles in the presence of substoichiometric acetic anhydride. Cyclization of the resulting enamines under Pinner conditions provided 2-halonicotinonitriles in high overall yields.
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