Soluble Polymer-Supported Ruthenium Porphyrin Catalysts for Epoxidation, Cyclopropanation, and Aziridination of Alkenes
作者:Jun-Long Zhang、Chi-Ming Che
DOI:10.1021/ol0259138
日期:2002.5.1
[reaction: see text] Attachment of poly(ethyleneglycol) (PEG) to ruthenium porphyrin via a covalent etheric bond gives soluble polymer-supported ruthenium catalysts 3-5. These catalysts exhibit high reactivity and selectivity toward alkene epoxidation with 2,6-dichloropyridine N-oxide and alkene cyclopropanation with diazo compounds. The application of these catalysts in the synthesis of unstable
Ruthenium(II) Porphyrin Catalyzed Formation of (<i>Z</i>)-4-Alkyloxycarbonyl- methylidene-1,3-dioxolanes from <i>γ</i>-Alkoxy-<i>α</i>-diazo-<i>β</i>-ketoesters
作者:Shi-Long Zheng、Wing-Yiu Yu、Chi-Ming Che
DOI:10.1021/ol010283f
日期:2002.3.1
[GRAPHICS]Ruthenum(II) porphyrins and dirhodium(II) acetate catalyze cyclization of gamma-alkoxy-alpha-diazo-beta-ketoesters to (Z)-4-(alkyloxycarbonylmethylidene)-1,3-dioxolanes selectively (ca. 68% yield) with no formation of 3(2H)-furanones. Reacting a diazo ketoester with [Ru-II(TTP)(CO)] [H2TTP = meso-tetrakis(p-tolyl) porphyrin] in toluene afforded a ruthenium carbenoid complex, which has been isolated and spectroscopically characterized. A mechanism involving hydrogen atom migration from the C-H bond to the ruthenium carbenoid is proposed.
Tao Ye, McKervey M. Anthony, Brandes Bridget D., Doyle Michael P., Tetrahedron Lett, 35 (1994) N 39, S 7269-7272
作者:Tao Ye, McKervey M. Anthony, Brandes Bridget D., Doyle Michael P.