415678-74-9Relevant academic research and scientific papers
Ruthenium(II) porphyrin catalyzed formation of (Z)-4-alkyloxycarbonyl-methylidene-1,3-dioxolanes from γ-alkoxy-γ-diazo-β-ketoesters
Zheng, Shi-Long,Yu, Wing-Yiu,Che, Chi-Ming
, p. 889 - 892 (2007/10/03)
(equation presented) R1 = aryl, allyl R2= methyl, 2,4-dimethyl-3-pentyl and (-)-menthyl Ruthenum(II) porphyrins and dirhodium(II) acetate catalyze cyclization of γ-alkoxy-α-diazo-β-ketoesters to (Z)-4-(alkyloxycarbonylmethylidene)-1,3-dioxolanes selectively (ca. 68% yield) with no formation of 3(2H)-furanones. Reacting a diazo ketoester with [RuII(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.
Stereoselective synthesis of disubstituted 3(2H)-furanones via catalytic intramolecular C-H insertion reactions of α-diazo-β-keto esters including asymmetric induction
Brandes, Bridget D.
, p. 7269 - 7272 (2007/10/02)
Rhodium(II) catalysed decomposition of γ-alkoxy-α-diazo-β-ketoesters produce cis-2,5-disubstituted-3(2H) furanones with high (> 97%) stereoselectivity. The combination of a chiral auxiliary in the ester moiety of the diazo precursor and a chiral catalyst can lead to asymmetric synthesis with diastereoselectivities up to 61% de.
