描述了几种 3,3-二取代的 2-芳基丙烯酸的合成。芳基乙醛酸酯和异亚丙基三苯基正膦之间的 Wittig 反应提供了一条有效的途径来制备 2-芳基-3-甲基巴豆酸酯。这些酯用 N-溴代琥珀酰亚胺溴化得到 3-溴甲基-2-芳基巴豆酸酯和-2-芳基异巴豆酸酯的混合物。3-溴甲基巴豆酸酯在加热时环化成内酯。还制备了2-芳基-3-叠氮甲基异巴豆酸和3-氨基甲基-2-苯基异巴豆酸。已从α-甲基-和α-乙基肉桂酸酯开始,开发了一种立体定向路线,用于制备 3-叠氮甲基-2-苯基异巴豆酸和顺式-3-叠氮甲基-2-苯基-2-戊烯酸。La synth8se de plusieurs acides aryl-2 acryliques dissubstituks en position-3,3 est dkcrite。La 反应 de Wittig effectuk entre desesters arylglyoxyliques
Development of a polymer bound Wittig reaction and use in multi-step organic synthesis for the overall conversion of alcohols to β-hydroxyamines
作者:Martin H. Bolli、Steven V. Ley
DOI:10.1039/a803612h
日期:——
An efficient combinatorial access to β-hydroxyamines suitable for automation is achieved by the mild oxidation of alcohols to aldehydes by polymer supported perruthenate (PSP), the subsequent clean olefination of the obtained aldehydes by polymer supported Wittig reagents followed by the epoxidation of the olefins by dimethyldioxirane (DMDO), and the final aminolysis of the epoxides with various amines is described.
Pd-Catalyzed C═C Double-Bond Formation by Coupling of <i>N</i>-Tosylhydrazones with Benzyl Halides
作者:Qing Xiao、Jian Ma、Yang Yang、Yan Zhang、Jianbo Wang
DOI:10.1021/ol901876w
日期:2009.10.15
Pd-catalyzed reaction of N-tosylhydrazones with benzylhalides affords di- and trisubstituted olefins in high yields with excellent stereoselectivity. This coupling reaction is supposed to proceed through a migratory insertion of Pd carbene species.
Divergent Reactivity of Alkyl Aryl Sulfones with Bases: Selective Functionalization of<i>ortho</i>-Aryl and α-Alkyl Units Enabled by a Unique Carbanion Transmetalation
作者:Lucie Řehová、Ivana Císařová、Ullrich Jahn
DOI:10.1002/ejoc.201301553
日期:2014.3
metalation selectivity of branched alkylarylsulfones is described. Such sulfones were found to initially undergo directed ortho-metalation with good regioselectivity, despite having a more acidic α-H atom. The structure of the alkylunit profoundly, but predictably, influences the regioselectivity of the attack of the base. In β- and γ-branched ortho-(alkylsulfonyl)aryllithiums a transmetalation to the
Metalation of methallylbenzenes with BuLi gave dilithio derivatives which were dialkylated with methyl bromide. Derivatives of cross conjugated dianions are obtained preferentially to linear ones. The parent trimethylenemethane dianion2 was obtained by metalation of isobutene. Energies and atomic net charges of these and related molecules were calcualted. The question of the aromaticity of these systems