Production of Aromatic Nitriles

Recent developments and perspectives in palladium-catalyzed cyanation of aryl halides: synthesis of benzonitriles

“…On the ton-scale the method of choice in industry is ammoxidation, whereby the corresponding toluene derivatives are reacted with oxygen and ammonia at 300-550 1C in the presence of heterogeneous fixed-bed catalysts (Scheme 2). [23][24][25] A drawback of the Rosenmund-von Braun and the Sandmeyer reactions is the use of stoichiometric amounts of copper(I) cyanide as a cyanating agent, which leads to equimolar amounts of heavy metal waste. Other disadvantages of the Rosenmund-von Braun reaction are the relatively high temperature (150-250 1C) and the low reactivity of aryl chlorides and bromides (in general the use of expensive aryl iodides is required).…”

Improving palladium-catalyzed cyanation of aryl halides: development of a state-of-the-art methodology using potassium hexacyanoferrate(II) as cyanating agent

“…On ton-scale the method of choice in industry is ammoxidation, whereby the corresponding toluene derivatives are reacted with oxygen and ammonia at 300-550°C in the presence of heterogeneous fixed-bed [23][24][25]. Unfortunately, the ammoxidation is restricted to products such as benzonitrile, terephthalodinitrile, and chlorobenzonitriles [26,27] because of the high temperature and high pressure needed.…”

Pd@CeO2‐catalyzed cyanation of aryl iodides with K4Fe(CN)6·3H2O under visible light irradiation

“…[7,8] Besides, ammoxidation of toluene is also often applied in the transformation from toluene to aromatic nitriles in industry (Scheme 1). [9][10][11] However, they are operated at harsh conditions, such as high temperatures and high-pressure conditions. For optimizing the conditions of cyanation reactions, an interesting protocol of transition metal catalysis has been explored and developed by chemists.…”