An unreported product outcome from an intended Sonogashira coupling is presented. The generality of this finding has been demonstrated by screening of a range of precatalysts. Mechanistic studies are consistent with the tetraaryl benzene product forming by interception of the aryl halide oxidative addition intermediate by repeated acetylene insertion.
Jones, R. C., Canty, A. J., Caradoc-Davies, T., Davies, N. W., Gardiner, M. G., Marriott, P., Ruhle, C. P. G., & Tolhurst, V. -A. (2010). A new mechanistic pathway under Sonogashira reaction protocol involving multiple acetylene insertions. Dalton Transactions, 39(16), 3799 - 3801. https://doi.org/10.1039/c001109f