320341-84-2

Upstream product

• 100-47-0 benzonitrile 
• 130777-67-2 ((1,2-bis(diisopropylphosphino)ethane)NiH)2 
• 130777-67-2 [(bis(diisopropylphosphino)ethane)Ni(H)]2 

Relevant academic research and scientific papers

Lewis Acid Assisted C-CN Cleavage of Benzonitrile Using [(dippe)NiH] 2

Reactions of [(dippe)NiH] 2 with benzonitrile and varying concentrations of Lewis acids (primarily BPh 3 and BF 3) have shown a dramatic variation of reaction rate compared to the same reaction without Lewis acids. When less than one equivalent of Lewis acid is used, the reaction rate is as much as 100 times greater than without Lewis acid. Boron exchange was observed with less than one equivalent of Lewis acid allowing the formation of a Ni(0)-η 2 -aryl complex (observed by low-temperature NMR and calculations) to which the Lewis acid is postulated to re-coordinate as the rate-limiting step allowing the formation of a stable Ni(II) product. When one equivalent or greater of Lewis acid is used, the reaction shows dramatic inhibition even compared to the reaction without Lewis acid. Lewis acid dissociation can be considered as the rate-limiting step under these conditions. The overall work detailed herein has shown the importance of Lewis acids in the activation of benzonitriles due to the strengthening of the C-N bond allowing for increased stabilization of the products.

Experimental and theoretical examination of C-CN bond activation of benzonitrile using zerovalent nickel

The nickel(0) fragment [Ni(dippe)] was reacted with benzonitrile and initially formed both η2-nitrile and η2-arene complexes at -60°C. When the sample was warmed to room temperature, the latter completely converted to the η2/su

Cleavage of carbon-carbon bonds in aromatic nitriles using nickel(0)

The nickel(0) fragment [(dippe)Ni] has been found to react with a variety of aromatic nitriles. Initial π-coordination to the C=C and CN bonds of 2-cyanoquinoline is found to lead ultimately to C-CN oxidative addition. 3-Cyanoquinoline reacts similarly, although no η2-CN complex is observed. 2-, 3-, And 4-cyanopyridines react initially to give η2-nitrile complexes that then lead to quantitative formation of C-CN oxidative addition products. Benzonitrile reacts similarly but undergoes reversible insertion into the Ph-CN bond to give an equilibrium mixture of Ni(II) and Ni(0) adducts. A series of para-substituted benzonitriles has been studied in terms of both the position of the equilibrium between (dippe)Ni(η2-arylnitrile) (dippe)-Ni(CN)(aryl) and the rate of approach to equilibrium, and the Hammett plots indicate a buildup of negative charge at the ipso carbon both in the transition state and the Ni(II) product. Terephthalonitrile gives both η2-nitrile and oxidative addition adducts, as well as dimetalated products. No C-C or C-N cleavage of the aromatic ring is seen with quinoline or acridine; only η2-arene complexes are formed. The structures of many of these compounds are supported by x-ray data.

Reversible cleavage of carbon-carbon bonds in benzonitrile using nickel(0)

The nickel(0) fragment [(dippe)Ni] has been found to π-coordinate to the CN bond of benzonitrile and undergo reversible insertion into the Ph-CN bond.