An unprecedented catalytic reaction using gold(I) complexes

Ligand Effects in Homogeneous Au Catalysis

“…Approximately 5 years after the original Baker/Westcott report, Hosomi reported a Au(I)-catalyzed hydrosilylation of aldehydes and ketones 159. When a colorless DMF solution of benzaldehyde and triphenylphosphinegold(I) chloride was treated with dimethylphenylsilane, a rapid darkening of the reaction mixture to deep purple occurred, and a metallic precipitate was formed.…”

Dehydrogenative Dimerization of Tin Hydrides Catalyzed by Ruthenium-Allenylidene Complexes

“…These allenylidene systems are slower and shorter-lived than the Fe ± Pd bimetallic catalysts of Braunstein et al (maximum turnover frequency of ca. 8000 s À1 and turnover number of 1 Â 10 6 ) [4,7] but more potent than simple Pd (300 ± 2000 turnovers) [3,4] or Au [6] catalysts.…”

“…(1)] is known to be catalyzed by a diverse set of transition metal complexes, including simple Pd II precursors, [2±4] [Cp 2 YH] (Cp cyclopentadiene), [5] and [(PPh 3 )AuCl]. [6] By far the most active catalysts are several diphosphane-bridged Fe/Pd heterobimetallic complexes in which the reaction is thought to occur at the Pd center, while the Fe center is proposed to play an important supporting role. [4,7] Similar dehydrogenative pathways are presumably employed in the synthesis of oligomeric and polymeric diorganostannanes from tin dihydrides, [4] including reactions catalyzed by low-valent metallocene or Group VI hexacarbonyl complexes.…”

Organometallic Polymers of Germanium, Tin and Lead

“…The same catalysts were used in the dehydrogenative coupling of n-Bu 3 SnH for which cross-linked polystannanes were observed as minor products 103 . In both cases, the formation of cross-linked polystannanes is suggested to result from a combination of disproportionation and dehydrocoupling.…”