Gold Catalysis: First Applications of Cationic Binuclear Gold(I) Complexes and the First Intermolecular Reaction of an Alkyne with a Furan

Abstract

Reaction of the cationic binuclear gold(I) complex [(Ph 3 PAu) 2 Cl]BF 4 with w-alkynylfurans furnished phenols as the major product and anellated furans as the side-products. The analogous trimesitylphosphane complex [(Mes 3 PAu) 2 Cl]BF 4 selectively afforded only the phenols. The latter catalyst then enabled the first intermolecular gold-catalyzed phenol synthesis.

Enantiomerically pure tetrahydroisoquinolines from the gold-catalysed isomerization of substrates derived from furans and amino acids

“…This synthesis is based on a sequence which included the condensation of a furfural derivative 1 and an amino acid derivative 2, the catalytic asymmetric hydrogenation of 3 and the goldcatalysed cycloisomerization to give the phenol 6 [17][18][19][20][21][22][23][24][25][26][27][28][29] as key steps.…”

Gold(I) Complexes of KITPHOS Monophosphines: Efficient Cycloisomerisation Catalysts

“…[5] Chloride-bridged dinuclear gold(I) complexes have recently been shown to be efficient catalysts for the cyclisation of w-alkynylfurans while their mononuclear counterparts failed to provide acceptable results and that the dimer based on the bulky trimesitylphosphine, PMes 3 , was markedly more active than its triphenylphosphine counterpart. [6] Gold(I) phosphine-based catalysts are most commonly prepared by substitution of the weakly coordinated tht (tht = tetrahydrothiophene) or Me 2 S in (tht)AuCl or (Me 2 S)AuCl, respectively, with an appropriate phosphine to afford 2, which is typically converted into the active catalyst in situ by removal of the chloride with a silver salt of a non-coordinating counterion. However, rather than generating the catalyst in situ we have found it more reproducible, convenient and time efficient to prepare complexes of the type [LAuA C H T U N G T R E N N U N G (NTf 2 )] (3) which do not need to be activated for catalysis and are stable with respect to long-term storage.…”

Gold‐Catalyzed Benzylic CH Activation at Room Temperature

“…Table 2 shows that when AuCl 3 served as catalyst, the initially obtained 2 undergoes significant decomposition (2 a and 2 c) or conversion was low (2 b, 55 % of the substrate was recovered). In contrast, the Au I catalyst [8] led to good conversion and good yields when the substituent R was sterically shielding (2 b and 2 c but not 2 a).…”