1609944-53-7Relevant academic research and scientific papers
Silver-free two-component approach in gold catalysis: Activation of [LAuCl] complexes with derivatives of copper, zinc, indium, bismuth, and other lewis acids
Fang, Weizhen,Presset, Marc,Guerinot, Amandine,Bour, Christophe,Bezzenine-Lafollee, Sophie,Gandon, Vincent
, p. 5439 - 5446 (2014)
Complexes of type [LAuCl] (L=phosphine, phosphite, NHC and others) are widely employed in homogeneous catalysis, however, they are usually inactive as such and must be used jointly with a halide scavenger. To date, this role has mostly been entrusted to silver salts (AgSbF6, AgPF6, AgBF4, AgOTf, etc.). However, silver salts can be the source of deactivation processes or side reactions, so it is sometimes advisable to use silver-free cationic gold complexes, which can be difficult to synthesize and to handle compared with the more robust chloride. We show in this study that various Lewis acids of the transition and main group metal families are expedient substitutes to silver salts. We have tested CuI, Cu II, ZnII, InIII, SiIV, Bi III, and other salts in a variety of typical AuI-catalyzed transformations, and the results have revealed that [LAuCl] can form active species in their presence. Not just silver: Active gold species have been generated from the corresponding inactive chlorides by using Lewis acids that are not typical in gold chemistry (see figure). Instead of silver salts, complexes of Cu, Zn, In, Si, Bi, and others have been used. This study shows that silver salts, which can cause deactivation processes and side reactions, can be replaced by various activators. Thus, the use of a sensitive cationic gold complex can be avoided.
