Highly selective palladium–benzothiazole carbene-catalyzed allylation of active methylene compounds under neutral conditions
作者:Antonio Monopoli、Pietro Cotugno、Carlo Giorgio Zambonin、Francesco Ciminale、Angelo Nacci
DOI:10.3762/bjoc.11.111
日期:——
The Pd-benzothiazol-2-ylidene complex I was found to be a chemoselective catalyst for the Tsuji-Trost allylation of active methylene compounds carried out underneutralconditions and using carbonates as allylating agents. The proposed protocol consists in a simplified procedure adopting an in situ prepared catalyst from Pd2dba3 and 3-methylbenzothiazolium salt V as precursors. A comparison of the
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。
Palladium(0)-Catalyzed Substitution of Allylic Substrates in a Two-Phase Aqueous-Organic Medium
作者:Mohamed Safi、Denis Sinou
DOI:10.1016/s0040-4039(00)78898-8
日期:1991.4
Palladium(0)-catalyzed substitution of allylic substrates are shown to occur in a two-phase aqueous-organic medium using the sulfonated triphenylphosphine P(C6H4-m-SO3Na)3 or (tppts) as the ligand, allowing the easy recovery and recycling of the catalyst.
使用磺化三苯膦P(C 6 H 4 -m-SO 3 Na)3或(tppts)作为配体,钯(0)催化的烯丙基底物取代发生在两相水性有机介质中易于回收和回收催化剂。
Palladium catalyzed c-allylation of highly acidic carbo and heterocyclic β-dicarbonyl compounds
作者:M. Prat、M. Moreno-Mañas、J. Ribas
DOI:10.1016/s0040-4020(01)86091-9
日期:1988.1
Highly acidic carbo and heterocyclic β-dicarbonyl compounds such as barbituric acid, 3,5-dimethyl-2-1,2,6-thiadiazine 1,1-dioxide, cyclohexane-1,3-dione, tetronicacids, Meldrum acid and 1,2-diphenylpyrazolidine-3,5-dione are efficiently C-allylated with primary and secondary allylating agents under palladium catalysis.
Efficient Metal-Catalyzed Direct Benzylation and Allylic Alkylation of 2,4-Pentanediones
作者:Magnus Rueping、Boris J. Nachtsheim、Alexander Kuenkel
DOI:10.1021/ol063048b
日期:2007.3.1
[reaction: see text] A highly effective metal-catalyzed benzylation and allylic alkylation of 2,4-pentanediones has been developed. This new bismuth-catalyzed direct carbon-carbon bond forming reaction provides the corresponding monoalkylated dicarbonyl compounds in high yields after short reaction times using the lowest amounts of catalyst (1 mol %) and the free alcohol. In addition, a new route to