An Efficient Approach to 2-Bromoalken-3-ols by Regioselective Bromohydroxylation Reaction of Simple Allenes with NBS
作者:Wangqing Kong、Binjie Guo、Chunling Fu、Shengming Ma
DOI:10.1002/ejoc.201001676
日期:2011.4
A regioselectivebromohydroxylationreaction of simpleallenes affording 2-bromoalken-3-ols in moderate-to-good yields has been developed by using NBS as the electrophilic reagent in a mixture of 1,4-dioxane/H 2 O (1:1) at room temperature. Through this study it has been concluded that the regioselectivity is determined by various factors including steric and electronic effects of the substituents
通过在 1,4-二恶烷/H 2 O (1:1) 混合物中使用 NBS 作为亲电试剂,开发了简单丙二烯的区域选择性溴羟基化反应,以中等至良好的收率提供 2-bromoalken-3-ols在室温下。通过这项研究得出的结论是,区域选择性由各种因素决定,包括丙二烯部分取代基的空间和电子效应。
Synthesis and Functionalization of Allenes by Direct Pd‐Catalyzed Organolithium Cross‐Coupling
作者:Jaime Mateos‐Gil、Anirban Mondal、Marta Castiñeira Reis、Ben L. Feringa
DOI:10.1002/anie.201913132
日期:2020.5.11
A palladium-catalyzed cross-coupling between in situ generated allenyl/propargyl-lithium species and arylbromides to yield highly functionalized allenes is reported. The direct and selective formation of allenic products preventing the corresponding isomeric propargylic product is accomplished by the choice of SPhos or XPhos based Pd catalysts. The methodology avoids the prior transmetalation to other
Conformational effects in compounds with six-membered rings—VIII
作者:F.G. Riddell、M.J.T. Robinson
DOI:10.1016/s0040-4020(01)98146-3
日期:1971.1
preferred orientations of ethyl and isopropyl groups in 1-alkyl-3,3-diphenylallenes and in 2-alkyl-1,3-dioxanes and -dioxolanes have been determined from the temperature dependence of the spin-spin coupling constants for appropriate vicinal protons. In the allenes a methyl group rather than a hydrogen atom eclipses a double bond but in the cyclic acetals skew interactions between methyl groups and oxygen
Chemistry of singlet oxygen. Dye-sensitized photooxygenation of arylallenes
作者:Ihsan Erden、Tomas R. Martinez
DOI:10.1016/s0040-4039(00)85981-x
日期:1991.4
1-Arylallenes react with singletoxygen via 1,2-and 1,4-cycloaddition modes giving rise to three types of carbonyl fragments. 1,1-Diphenyl- and 1-methyl-1-phenylallenes react predominantly by the 1,4-mode. Plausible mechanisms are discussed for the formation of the observed products.
Indene-2-carboxylic acids are prepared from allenylbenzenes and CO2 by an AlBr3-mediated tandem reaction consisting of intramolecular Friedel–Crafts alkylation of allenylbenzenes and subsequent car...