Features and Applications of [Rh(CO)<sub>2</sub>Cl]<sub>2</sub>-Catalyzed Alkylations of Unsymmetrical Allylic Substrates
作者:Brandon L. Ashfeld、Kenneth A. Miller、Anna J. Smith、Kristy Tran、Stephen F. Martin
DOI:10.1021/jo701290b
日期:2007.11.1
A novel regio- and stereoselective [Rh(CO)2Cl]2-catalyzed allylic alkylation of unsymmetrical allylic carbonates was discovered. The regioselectivity of the reaction favors product ratios in which substitution occurs at the carbon bearing the leaving group. When an enantiomerically enriched carbonate (≥99% ee) was examined, the Rh(I)-catalyzed allylic alkylation proceeded stereoselectively to provide
Thioureas as Ligands in the Pd-Catalyzed Intramolecular Pauson−Khand Reaction
作者:Yefeng Tang、Lujiang Deng、Yangdong Zhang、Guangbin Dong、Jiahua Chen、Zhen Yang
DOI:10.1021/ol050410y
日期:2005.4.14
[reaction: see text] The thiourea-Pd complex was established as a novel type of catalyst in the PKR of allylpropargylamine, and the demonstrated chemistry may prove to be valuable for developing thiuorea as a ligand for the Pd-catalyzed Pauson-Khandreaction.
Tetramethyl Thiourea/Co<sub>2</sub>(CO)<sub>8</sub>-Catalyzed Pauson−Khand Reaction under Balloon Pressure of CO
作者:Yefeng Tang、Lujiang Deng、Yandong Zhang、Guangbin Dong、Jiahua Chen、Zhen Yang
DOI:10.1021/ol047651a
日期:2005.2.1
A Pauson-Khandtype of conversion of enynes to bicycliccyclopentenones employing the commercially available Co2(CO)8 and tetramethylthiourea (TMTU) as catalysts is described. This method allows a variety of enynes with diverse functional groups to be cyclized into cyclopentenones of interest. [reaction: see text]
Effect of Lithium Chloride on Tuning the Reactivity of Pauson-Khand Reactions Catalyzed by Palladium-Tetramethylthiourea
作者:Jia-Hua Chen、Aiwen Lei、Zhen Yang、Lu-Jiang Deng、Jing Liu、Ji-Qing Huang、Yanhe Hu、Mao Chen、Yu Lan
DOI:10.1055/s-2007-983796
日期:2007.8
A general and robust transition-metal-catalyzed Pauson-Khandreaction is still difficult to achieve. In this contribution, we describe our recent observations on the effect of lithium chloride on Pauson-Khandreactionscatalyzed by palladium(II) chloride-tetra-methylthiourea; this allows structurally diverse cyclopentenones to be prepared effectively.
Pauson–Khand reactions catalyzed by entrapped rhodium complexes
作者:Kang Hyun Park、Seung Uk Son、Young Keun Chung
DOI:10.1016/s0040-4039(03)00434-9
日期:2003.3
An entrapped Rh complex prepared by a sol–gel process has been used as a catalyst in the Pauson–Khandreaction under mild reaction conditions; the catalyst is easily recovered and reused at least 10 times without losing catalyst activity.