415678-69-2Relevant academic research and scientific papers
anti-Selective aldol reactions of chiral alcohol substituted γ-benzyloxyl vinylogous urethanes and the synthesis of 3-benzyloxyl-4-hydroxylalkan-2-ones
Li, Yu-Jang,Chung, Chuan-Chung,Chen, Pin-Zu
, p. 1573 - 1581 (2017)
The anti-selective aldol reaction of chiral alcohol-substituted γ-benzyloxy vinylogous urethanes is described. The use of (1S,2R,4R)-1-(hydroxydiphenylmethyl)-7,7-dimethylbicyclo[2,2,1]-heptan-2-ol as a chiral auxiliary in the aldol reaction of a vinylogous urethane enolate was found to provide anti-products in good yields with moderate to excellent enantioselectivities. The major anti-vinylogous urethane lactones were transformed into 3-benzyloxyl-4-hydroxylalkan-2-ones in good yields.
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.
