Why Excess Cyanide Can Be Detrimental to Pd-Catalyzed Cyanation of Haloarenes. Facile Formation and Characterization of [Pd(CN)_3(H)]~(2-) and [Pd(CN)_3(Ph)]~(2-)

摘要

Unexpected side reactions at the Pd center have been identified for Pd-catalyzed cyanation of haloarenes (eq 1). In the presence of excess cyanide, these reactions can proceed with ease, interfering with the key steps of the catalytic loop (Scheme 1) and thereby disrupting the process.