Bifunctionality of Zn dust in Ullmann C–C cross-coupling by Ni/Pd dual catalysis: theoretical insight

摘要

In the Ni/Pd catalysed electrophilic Ullmann coupling reaction, Zn powder presents bifunctionality as a heterogeneous reducing agent and an organic zinc reagent promoting transmetalation. Metal halides MXn as additives are indispensable to promoting the dissociation of ZnX2 from the Zn(101) surface in the mode ZnX2·MXn, which assists the transmetalation to achieve the C(sp2)–C(sp2) cross-coupling reaction.