Functionalized nitrogen ligands (C[sbnd]N) for palladium catalyzed cross-coupling reactions (part II).

Abstract In recent years, considerable effort has been focused in Pd catalyzed cross-coupling reactions, especially the use of less reactive and economically viable substrates like aryl chlorides. Unfortunately, Pd complexes containing the ligands having only N as a donor atom has some limitations, as it couples, mostly aryl iodides and bromides with different nucleophiles, and shows less activity towards aryl chlorides. This restriction can overwhelm by the use of Pd complexes containing N in combination with the C as a donor atom such as palladacycles, pincers, PEPPSI and carbene ligands. The advantages of these ligands include high activity with enhanced selectivity, less toxicity, moisture, air as well as thermal stability. Most importantly, such complexes have broad applications in catalysis under ambient conditions. This part of compressive review highlights the results of the highly active C N based Pd complexes and their applications in cross-coupling reactions. In the next part, we will cover all ligands and complexes containing N in combination with P, O and S as a donor atoms (Pd catalysts based on C P, C O and C S ligands). Though, the number of C N based Pd complexes containing Ferrocene and Buchwald ligands were reported for Pd catalyzed cross-coupling reaction, these complexes will be covered in the next part of the article. Graphical abstract Image 1 Highlights • Pd catalyzed cross coupling reaction of compounds containing C N bonds. • Update of the recent efforts made in the coupling reactions by Pd complexes based on the C N ligands. • The present part focused on the applications of the ligands containing C N as donor atoms. • Next part covers all ligands and catalysts containing N in combination with O, P and S as a donor atoms. [ABSTRACT FROM AUTHOR]