Module 11 : Transition Metal Catalysis

Lecture 35 : Nickel Catalysts

 

Examples:

S.-M. Yang, S. K. Nandy, A. R. Selvakumar, J.-M. Fang, Org. Lett. 2000 , 2 , 3719.

M. Couturier, J. L. Tucker, B. M. Andresen, P. Dube, J. T. Negri, Org. Lett. 2001 , 3 , 465.

B. Klenke, I. H. Gilbert, J. Org. Chem. 2001 , 66 , 2480.

11.9.2 Hydrocyanation

Organonitriles are key intermediates for the synthesis numerous compounds including polymers, fibers, agrochemicals, cosmetics and pharmaceuticals. Nickel complexes find wide applications for the hydrocyanation of alkenes and alkynes. For example, triarylphosphite nickel complex catalyzes the reaction of 1,3-butadiene with HCN to afford nylon 6,6-precursor AND (adiponitrile) by anti-Markovnikov fashion (Scheme 4). Using this process annually 1 billion pounds of AND is produced.

Scheme 4

11.9.3 Cross-Coupling Reactions

11.9.3.1 Negishi Coupling

Unsaturated alkyl bromide proceeds C-C cross-coupling with Et2Zn in the presence of Ni(acac)2 (Scheme 5). Under this condition, saturated alkyl bromide produces the bromide-zinc exchange product.

Scheme 5