Intermolecular Gold(I)-Catalyzed Alkyne Carboalkoxylation Reactions for the Multicomponent Assembly of β-Alkoxy Ketones
作者:Danielle M. Schultz、Nicholas R. Babij、John P. Wolfe
DOI:10.1002/adsc.201200825
日期:2012.12.14
A new gold(I)-catalyzed multicomponent synthesis of β-alkoxy ketones from aldehydes, alcohols, and alkynes is described. This atom economical synthesis was achieved through the use of the gold complex (SPhos)AuNTf2 as a catalyst, and allows for the preparation of a diverse array of β-alkoxy ketone products. Mechanistic studies illustrate that these reactions proceed via gold(I)-catalyzed hydrolysis
In the presence of a catalytic amount of mesoporous aluminosilicate (Al-MCM-41), both allyltrimethylsilane and silyl enol ether reacted with various acetals under mild reaction conditions to afford the corresponding homoallyl ethers and beta-alkoxy ketones, respectively. The catalyst was easily recovered from the reaction mixture and could be reused in the same reaction without a significant loss of catalytic activity. Moreover, Al-MCM-41 exhibited high chemoselectivity for acetal over aldehyde in the reactions. (C) 2010 Elsevier Ltd. All rights reserved.
Mesoporous aluminosilicate-catalyzed Mukaiyama aldol reaction of aldehydes and acetals
A mesoporous aluminosilicate (Al-MCM-41) was found to be an effective heterogeneous catalyst for the reaction of both aldehydes and acetals with silylenolethers or ketene silylacetals to give the corresponding aldol adducts in moderate to high yields. The remarkable high catalytic activity of Al-MCM-41 over amorphous silica-alumina and aluminum-free mesoporous silicate was observed in the reaction