RT info:eu-repo/semantics/article T1 Olefin Insertion Versus Cross-Coupling in trans-[Pd(Ar)X(AsPh3)2] Complexes (X = I, F, CF3) Treated with a Phosphine-EWOlefin Ligand to Induce Ar–X Coupling A1 Pozo, Juan del A1 Gioria, Estefanía A1 Espinet Rubio, Pablo K1 Phosphine K1 inserción de olefina AB Addition of the coupling promoter PEWO ligand 1-(Ph2P),2-(CH═CH–C(O)Ph)C6F4 (PhPEWO-F) to precursors with the displaceable AsPh3 ligand trans-[PdXAr(AsPh3)2] (X = I, F, CF3) fails to induce the pursued Ar–F or Ar–CF3 coupling and results in formation of products of olefin insertion into the Pd–Ar bond for X = I, CF3, and in Ar–Ar coupling for X = F. In the course of the processes, trans-[PdXAr(PhPEWO-F)(AsPh3)] intermediates are observed for X = I, F, CF3, with P-coordinated PhPEWO-F monodentate ligands and a dangling olefin group. For X = I, CF3, subsequent insertion of the double bond into the Pd–Ar bond and O-coordination gives rise to complexes with a P,C,O-pincer system. The observed insertion rates suggest that the limiting step toward insertion is the trans to cis isomerization, while insertion itself is very fast. This is supported by the fast insertion observed when PhPEWO-F is added to cis-[Pd(CF3)Ar(3-F-py)2]. The insertion mechanism in PhPEWO-F resembles the initial phase of the dearomative rearrangement mechanism reported for PdArBrL (L = dialkyl biaryl phosphine). PB American Chemical Society SN 0276-7333 YR 2017 FD 2017 LK http://uvadoc.uva.es/handle/10324/28847 UL http://uvadoc.uva.es/handle/10324/28847 LA eng NO Organometallics, 2017, 36 (15), p. 2884–2890 NO Producción Científica DS UVaDOC RD 27-dic-2024