Synthesis of 4-arylethyl-6-arylpyrimidine-2-thiols through aza-Michael addition/nucleophilic addition/aromatization tandem reactions
作者:Zheng Li、Wenli Song、Jiaojiao He、Yan Du、Jingya Yang
DOI:10.1515/hc-2017-0169
日期:2018.2.23
Abstract An efficient method for the synthesis of the title compounds by reactions of divinyl ketones with thiourea is described. This protocol has the advantages of high yields, mild reaction conditions and simple work-up procedure.
Synthesis of Optically Enriched Spirocyclic Benzofuran-2-ones by Bifunctional Thiourea-Base Catalyzed Double-Michael Addition of Benzofuran-2-ones to Dienones
A highly enantioselective catalytic double‐Michael addition reaction of substituted benzofuran‐2‐ones with divinyl ketones promoted by readily accessible tertiary amine–thiourea Cinchona alkaloids has been developed. A number of opticallyenrichedspirocyclic benzofuran‐2‐ones were prepared in very good yields (up to 99 %), diastereoselectivities (up to 19:1 d.r.), and very good enantioselectivities
Gold(I)-Catalyzed Desymmetrization of 1,4-Dienes by an Enantioselective Tandem Alkoxylation/Claisen Rearrangement
作者:Hongmiao Wu、Weiwei Zi、Guigen Li、Hongjian Lu、F. Dean Toste
DOI:10.1002/anie.201503357
日期:2015.7.13
An enantioselective alkoxylation/Claisen rearrangement reaction was achieved by a strategic desymmetrization of 1,4‐dienes under the catalysis of (S)‐DTBM‐Segphos(AuCl)2/AgBF4. This reaction system was highly selective for the formation of 3,3‐rearrangement products, providing cycloheptenes with various substitutions in good yield and good to excellent enantioselectivity. This transformation was further
Tandem hydrogenation and condensation of fluorinated α,β-unsaturated ketones with primary amines, catalyzed by nickel
作者:Nahury Castellanos-Blanco、Marcos Flores-Alamo、Juventino J. García
DOI:10.1039/c5dt02366a
日期:——
°C to give the corresponding saturated carbonyl compounds; here hydrogenation of the CC bond was preferred over the CO bond. Under the same reaction conditions but using an excess of benzylamine, a tandem process is then favoured, starting also with the reduction of the CC bond followed by a nucleophilic addition of the primary amine to yield valuable saturated imines with good to excellent yields (62%–91%)