Heck reactions tricyclohexylphosphine

Normally, the oxidative addition of an aryl chloride to Pd(0) is reluctant to take place. But such a process is greatly accelerated in the presence of sterically hindered, electron-rich phosphine ligands [e.g., P(/-Bu)3 or tricyclohexylphosphine]. In late 1990s, Reetz [76] and Fu [77] successfully conducted intermolecular Heck reactions using arylchlorides as substrates, as exemplified by the conversion of p-chloroanisole to adduct 77 [77], The applications of this discovery will surely be reflected on future Heck reactions of non-activated heteroaryl chlorides. 

Xu, C., Gong, J.F., Yue, S.F. et al. (2006) Tricyclohexylphosphine-cyclopaUadated ferro-cenyhmine complexes synthesis, crystal stractures and application in Suzuki and Heck reactions. Dalton Trans., 4730-9. 

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