Hydroxylamine catalyzed Nazarov cyclizations of divinyl ketones
摘要:
The first examples of iminium catalyzed Nazarov cyclizations of divinyl ketones are presented. Experiments describing hydroxylamine catalysis of the cyclization of eight alpha-alkoxy divinyl ketones (60-79% yield) and one unactivated divinyl ketone (38% yield) are reported. Phenyl substitution at the beta-position of the divinyl ketone inhibits cyclization, whereas beta-alkyl substituted beta-alkoxy divinyl ketones readily cyclize. (C) 2015 Elsevier Ltd. All rights reserved.
Synthesis of Weinreb Amides via Pd-Catalyzed Aminocarbonylation of Heterocyclic-Derived Triflates
作者:A. Deagostino、Paolo Larini、Ernesto G. Occhiato、Lorena Pizzuto、Cristina Prandi、Paolo Venturello
DOI:10.1021/jo7024898
日期:2008.3.1
lactone-, and thiolactone-derived triflates into N-methoxy-N-methyl or morpholine Weinreb amides has been realized using Pd-catalyzed aminocarbonylation under CO atmospheric pressure and at room temperature. The carbonylative coupling can be efficiently carried out with 2% of catalyst in the presence of Xantphos as a ligand. The amides smoothly react with nucleophiles to afford acylated aza-, oxa-, and
High-yielding synthesis of Weinreb amides via homogeneous catalytic carbonylation of iodoalkenes and iodoarenes
作者:Attila Takács、Andrea Petz、László Kollár
DOI:10.1016/j.tet.2010.04.076
日期:2010.6
1-iodo-1-(1-naphthyl)ethene) were used as substrates in palladium-catalysed aminocarbonylation with N,O-dimethylhydroxylamine. The corresponding Weinreb amides were prepared in high isolated yields (up to 87%) when forcing conditions (40–60 bar of CO, 50 °C) were used. The aminocarbonylation provides the Weinreb amides as pure products in a chemoselective reaction. No formation of ketocarboxamides, due to double CO
碘代芳烃(碘代苯和2-碘代噻吩)和碘代烯烃(1-碘代环己烯,1-碘代-4-叔丁基环己烯,1-碘-2-甲基环己烯和1-碘-1-(1-萘基)乙烯)被用作底物N,O-二甲基羟胺在钯催化的氨基羰基化反应中的作用。当使用强制条件(40-60 bar CO,50°C)时,可以以较高的分离产率(高达87%)制备相应的Weinreb酰胺。氨基羰基化在化学选择性反应中提供了作为纯产物的Weinreb酰胺。除了2-碘噻吩外,即使在60 bar的CO压力下也未观察到由于双CO插入而导致的酮甲酰胺的形成。
Site‐selective Hydrogenation/Deuteration of Benzylic Olefins Enabled by Electroreduction Using Water
作者:Simon Kolb、Daniel B. Werz
DOI:10.1002/chem.202300849
日期:——
Electroreduction of benzylicolefins has been applied to site-selectively hydrogenate such double bonds while other functions that react under regular hydrogenation conditions are present. By the use of water as proton source this protocol also allows deuteration by simply switching to D2O. The applicability of this method was shown by the use of a commercially available electrolysis setup and a broad
苄基烯烃的电还原已应用于位点选择性氢化此类双键,同时存在在常规氢化条件下反应的其他功能。通过使用水作为质子源,该协议还允许通过简单地切换到 D 2 O 进行氘化。该方法的适用性通过使用商用电解装置和广泛的底物范围得到证明。
Regiospecific Synthesis of 3-Substituted 5-Alkylisoxazoles from Oxime Dianions and N-Methoxy-N-Methylalkylamides
作者:Theodore J. Nitz、Deborah L. Volkots、David J. Aldous、Richard C. Oglesby
DOI:10.1021/jo00098a054
日期:1994.9
Nitz Theodore J., Volkots Deborah L., Aldous David J., Oglesby Richard C., J. Org. Chem, 59 (1994) N 19, S 5828-5832
作者:Nitz Theodore J., Volkots Deborah L., Aldous David J., Oglesby Richard C.