Chemo-selective Stille-type coupling of acyl-chlorides upon phosphine-borane Au(i) catalysis
Nereida Hidalgo1,2, Arnaud Le Gac1, Sonia Mallet-Ladeira3
1CNRS/Université Paul Sabatier, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA UMR 5069) 118 Route de Narbonne 31062 Toulouse Cedex 09 France didier.bourissou@univ-tlse3.fr.
Abstract:
Phosphine-boranes do not promote oxidative addition of acyl chlorides to gold, but the phosphine-borane gold triflimide complex [iPr2P(o-C6H4)BCy2]AuNTf2 was found to catalyze the coupling of acyl chlorides and aryl stannanes. The reaction involves aryl/chloride-bridged dinuclear gold(i) complexes as key intermediates, as substantiated by spectroscopic and crystallographic analyses. Similar to Pd(0)/Pd(ii)-catalyzed Stille coupling with phosphine-borane ligands, the gold-catalyzed variant shows complete chemoselectivity for acyl chlorides over aryl iodides and bromides, enabling straightforward access to halogenated aryl ketones.
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