Boronate Urea Activation of Nitrocyclopropane Carboxylates
摘要:
Boronate ureas operate as catalysts for the activation of nitrocyclopropane carboxylates in nucleophilic ring-opening reactions. A variety of amines were found to open the urea-activated nitrocyclopropane carboxylates, generating highly useful nitro ester building blocks In good yields. Standard manipulations allow access to a wide range of valuable compounds from the ring-opened products with direct applications in bioactive target synthesis.
A Mild Procedure for the Lewis Acid-Catalyzed Ring-Opening of Activated Cyclopropanes with Amine Nucleophiles
摘要:
The Lewis acid-catalyzed ring-opening of methyl 1-nitrocyclopropanecarboxylates with amine nucleophiles is described. The reaction proceeds at room temperature and with complete preservation of the enantiomeric purity from the electrophilic center of the cyclopropane to the acyclic product. The methodology was applied in an enantioselective synthesis of the dual serotonin/norepinephrine reuptake inhibitor (3R)-3-(1H-indol-1-yl)-N-methyl-3-phenylpropan-1-amine.
Asymmetric Rh(II)-Catalyzed Cyclopropanation of Alkenes with Diacceptor Diazo Compounds: <i>p</i>-Methoxyphenyl Ketone as a General Stereoselectivity Controlling Group
作者:Vincent N. G. Lindsay、Cyril Nicolas、André B. Charette
DOI:10.1021/ja201237j
日期:2011.6.15
α-PMP-ketone group were found to be effective carbene precursors for the highly stereoselective Rh(2)(S-TCPTTL)(4)-catalyzed cyclopropanation of alkenes (EWG = NO(2), CN, CO(2)Me). The resulting products were readily transformed into a variety of biologically relevant enantiopure molecules, such as cyclopropane α- and β-amino acid derivatives. Different mechanistic studies carried out led to a rationale for the
Boronate Urea Activation of Nitrocyclopropane Carboxylates
作者:Sonia S. So、Tyler J. Auvil、Victoria J. Garza、Anita E. Mattson
DOI:10.1021/ol202873d
日期:2012.1.20
Boronate ureas operate as catalysts for the activation of nitrocyclopropane carboxylates in nucleophilic ring-opening reactions. A variety of amines were found to open the urea-activated nitrocyclopropane carboxylates, generating highly useful nitro ester building blocks In good yields. Standard manipulations allow access to a wide range of valuable compounds from the ring-opened products with direct applications in bioactive target synthesis.
A Mild Procedure for the Lewis Acid-Catalyzed Ring-Opening of Activated Cyclopropanes with Amine Nucleophiles
作者:Olga Lifchits、André B. Charette
DOI:10.1021/ol8009286
日期:2008.7.3
The Lewis acid-catalyzed ring-opening of methyl 1-nitrocyclopropanecarboxylates with amine nucleophiles is described. The reaction proceeds at room temperature and with complete preservation of the enantiomeric purity from the electrophilic center of the cyclopropane to the acyclic product. The methodology was applied in an enantioselective synthesis of the dual serotonin/norepinephrine reuptake inhibitor (3R)-3-(1H-indol-1-yl)-N-methyl-3-phenylpropan-1-amine.