- PROCESS FOR THE DIRECT ALPHA-METHYLENATION OF KETONES
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The invention relates to a process for preparing an α-methylene ketone comprising the step of reacting a ketone with formaldehyde in the presence of a catalyst which is an organic compound comprising at least one acid function or the corresponding salt, ester or amide thereof and at least one amine function or the corresponding ammonium salt, or a zwitterion thereof.
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Page/Page column 16; 17; 18
(2020/06/10)
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- One-pot conversion of biomass-derived xylose and furfural into levulinate esters via acid catalysis
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Direct conversion of biomass-derived xylose and furfural into levulinic acid, a platform molecule, via acid-catalysis has been accomplished for the first time in dimethoxymethane/methanol. Dimethoxymethane acted as an electrophile to transform furfural into 5-hydroxymethylfurfural (HMF). Methanol suppressed both the polymerisation of the sugars/furans and the Aldol condensation of levulinic acid/ester.
- Hu, Xun,Jiang, Shengjuan,Wu, Liping,Wang, Shuai,Li, Chun-Zhu
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p. 2938 - 2941
(2017/03/15)
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- A convenient synthesis of α-functional alkyl vinyl ketones
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Reaction of 2-functional alkyl-1,3-ketones with 30% aqueous formaldehyde using aqueous 6-10M potassium carbonate solution as base, afforded α-functional alkyl vinyl ketones in good yields.
- Ben Ayed,Amri
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p. 3813 - 3819
(2007/10/03)
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- An Annelation Approach to the Synthesis of Eudesmane and Elemane Sesquiterpene Lactones. Total Synthesis of dl-Dihydrocallitrisin, dl-7,8-Epialantolactone, dl-7,8-Epiisoalantolactone, and dl-Atractylon
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An annelation approach to the synthesis of eudesmane sesquiterpenes is described.The 1,6-annelation reagent α-carbomethoxy-β-methyl-γ-methylidene-Δα,β-butenolide (1) is used to construct the linear tricyclic lactone 2,5,6,7,8,8a,9,9aβ-octahydro-8aβ-methyl-2-oxonaphthofuran-3-carboxylic acid methyl ester (2).The conversion of 2 to dl-dihydrocallitrisin (3), dl-7,8-epialantolactone (4), dl-7,8-epiisoalantolactone (5), and dl-atractylon (6) is detailed.Studies directed toward synthesis of the elemane sesquiterpene lactones vernomenin and vernolepin also are presented.
- Schultz, Arthur G.,Godfrey, Jollie D.
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p. 2414 - 2428
(2007/10/02)
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