Cyclometallated gold(iii) aryl-pyridine complexes as efficient catalysts for three-component synthesis of substituted oxazolesElectronic supplementary information (ESI) available: Copies of 1H NMR, 13C NMR, and 19F NMR spectra for (dfppyH)AuCl35b. SC-XRD data for compounds 2, 3, 5b, and 6b in cif format. CCDC 1022615-1022618. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4dt03806a

• Main Authors: von Wachenfeldt, Henrik, Polukeev, Alexey V, Loganathan, Nagarajan, Paulsen, Filip, Röse, Philipp, Garreau, Marion, Wendt, Ola F, Strand, Daniel
• Format: Journal Article
• Language: English
• Published: 10.03.2015
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c4dt03806a

Cyclometallated aryl-pyridine gold( iii ) complexes are shown to be efficient catalysts for the multicomponent reaction between N -benzyl imines, alkynes, and acyl chlorides to form trisubstituted oxazoles. The reaction typically proceeds in good yields (up to over 80%) and short reaction times (∼15 minutes). The high stability of the investigated cyclometallated catalysts enables a retained efficiency for this reaction in terms of rate and yield using as little as 0.5 mol% catalyst, a reduction by an order of magnitude compared to previously used Au( iii )-salen complexes. An attractive feature of the present catalytic system is that active catalysts can be formed from simple pre-catalysts under the reaction conditions. Both cyclometallated and non-cyclometallated complexes were characterized in the solid state by single crystal X-ray diffraction. Cyclometallated gold( iii ) complexes efficiently catalyze the multicomponent reaction between imines, alkynes, and acyl chlorides to form trisubstituted oxazoles.