Monoallylation and monoalkylation of diketones and β-keto esters with allylic and benzylic alcohols catalysed by [Cp*Co(CH3CN)3][SbF6]2 (I) are reported. The method does not require any additive and affords regioselective products. The mechanistic investigations were done by in situ 1H NMR spectroscopy as well as control experiments. It has been shown that reactions proceed via η3-allyl complex formation or
报道了[Cp*Co(CH 3 CN) 3 ][SbF 6 ] 2 ( I )催化的二酮和β-酮酯与烯丙醇和苄醇的单烯丙基化和单烷基化。该方法不需要任何添加剂并提供区域选择性产物。通过原位1 H NMR 光谱以及对照实验进行了机理研究。已表明反应通过形成 η 3 -烯丙基络合物或烯丙基醚中间体进行。烷基化仅通过醚中间体发生。所得烯丙基化和烷基化产物已用于合成十一种新的三取代吡唑和一种吡唑啉酮。
Alxylations of α-methyl substituted β-diketones throught their Cu(II) complexes. Preparation of sterically congested β-diketones.
作者:María E. Lloris、Jorge Marquet、Marcial Moreno-Mañas
DOI:10.1016/s0040-4039(00)88524-x
日期:1990.1
The copper(II) complexes of 3-methylpentane-2,4-dione and 2-methyl-1-phenylbutane-1,3-dione are good substrates for C-alkylation with several alkyl bromides including 1-bromoadamantane and 9-bromofluorene. Sterically congested β-diketones have been prepared.
Reactions of copper(II) β-diketonates under free radical conditions. Preparation of highly congested β-diketones.
作者:María E. Lloris、Nicanor Gálvez、Jorge Marquet、Marcial Moreno-Mañas
DOI:10.1016/s0040-4020(01)81955-4
日期:1991.9
Copper(II) β-diketonates react with alkyl bromides under freeradical conditions to give highly congested β-diketones such as 3-(1-adamantyl)-3-alkylpentane-2,4-diones. Another typical freeradical reagent: benzoyl peroxide, reacts also functionalizing the intercarbonyl positions.