Copper-promoted cyanation of aryl iodides with N,N-dimethyl aminomalononitrile

Palladium-Catalyzed Denitrative Synthesis of Aryl Nitriles from Nitroarenes and Organocyanides

A denitrative cyanation of nitroarenes using organocyanides and a palladium catalyst was developed. The key for this reaction was the utilization of an aminoacetonitrile as a cyano source to avoid the generation of stoichiometric metal- and halogen-containing chemical waste. A wide range of nitroarenes, including heteroarenes and pharmaceutical molecules, can be converted into aryl nitriles.

Nickel-Catalyzed Reductive Alkyne Hydrocyanation Enabled by Malononitrile and a Formaldehyde Additive

The development of a nickel-catalyzed reductive alkyne hydrocyanation is described using 2-methyl-2-phenylmalononitrile (MPMN), a C-bound electrophilic transnitrilation reagent. Reproducibility issues led to the detection of oxidized hemiaminal impurities within N,N-dimethylacetamide. These impurities release formaldehyde in situ, which was ultimately identified as a critical reaction additive. A range of diaryl and aryl-alkyl alkynes underwent hydrocyanation. Mechanistic experiments revealed that formaldehyde and MPMN undergo a Ni-catalyzed reductive coupling of two π-components, leading to the controlled release of glycolonitrile as the active cyanating agent.

AIBN as an Electrophilic Reagent for Cyano Group Transfer

AIBN is a convenient electrophilic cyanation reagent for transforming ArLi into ArCN under mild conditions. The addition/fragmentation cascade is controlled by Li···N chelation in which AIBN nitrogens assist in the nearly barrierless fragmentation into the desired ArCN product. Acidic C-H bonds in the fragmented byproduct partially consume ArLi by protonation. Density functional theory calculations and isotopic labeling probe the mechanism and explain the switch to substituted hydrazones in reactions with BuLi.

Application of combined cyanide sources in cyanation reactions

The cyanation reaction is a key transformation due to the wide-ranging applications of nitrile compounds in organic chemistry. Traditionally, the cyanation reaction employs metal cyanides as cyanide sources, which are toxic and environmentally unfriendly. Very recently, many excellent examples of using combined cyanide sources as cyanating agents have been reported. This review summarizes the applications of combined cyano-group sources in a variety of cyanation reactions.