Synthesis of 3,4-difluorobenzonitrile and monofluorobenzonitriles by means of halogen-exchange fluorination was written by Suzuki, Hiroshi;Kimura, Yoshikazu. And the article was included in Journal of Fluorine Chemistry in 1991.Application of 2670-38-4 This article mentions the following:
3,4-Difluorobenzonitrile has been prepared by a halogen-exchange reaction between 3,4-dichlorobenzonitrile and spray-dried potassium fluoride in the presence of tetraphenylphosphonium bromide in refluxing 1,3-dimethylimidazolidine-2-one (DMI). In the fluorination reaction, 4-chloro-3-fluorobenzonitrile seems to be a key intermediate. 2-, 3-, And 4-fluorobenzonitriles have also been produced from the corresponding chlorobenzonitriles by halogen-exchange at 290° in DMI in a pressure reactor. In the experiment, the researchers used many compounds, for example, 3,4-Dichlorobenzamide (cas: 2670-38-4Application of 2670-38-4).
3,4-Dichlorobenzamide (cas: 2670-38-4) belongs to amides. Because of the greater electronegativity of oxygen, the carbonyl (C=O) is a stronger dipole than the N–C dipole. The presence of a C=O dipole and, to a lesser extent a N–C dipole, allows amides to act as H-bond acceptors. Ionic, or saltlike, amides are strongly alkaline compounds ordinarily made by treating ammonia, an amine, or a covalent amide with a reactive metal such as sodium.Application of 2670-38-4
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics