71443-23-7Relevant academic research and scientific papers
Silica gel enables Achmatowicz rearrangement with KBr/oxone under “anhydrous” condition for one-pot functionalization
Zhao, Guodong,Tong, Rongbiao
, p. 1669 - 1675 (2019/01/04)
Silica gel was found to effectively promote Achmatowicz rearrangement (AchR) using KBr/oxone under near anhydrous condition. This new protocol allows direct functionalization of AchR products in a one-pot manner, effectively reducing the cost, time, and e
Asymmetric synthesis of trans-4,5-dioxygenated cyclopentenone derivatives by organocatalyzed rearrangement of pyranones and enzymatic dynamic kinetic resolution
Nunes, Jo?o P.M.,Veiros, Luís F.,Vaz, Pedro D.,Afonso, Carlos A.M.,Caddick, Stephen
supporting information; experimental part, p. 2779 - 2787 (2011/05/02)
Dioxygenated cyclopentenones are versatile building blocks for the synthesis of several natural products. Herein we report a direct asymmetric synthesis of trans-4,5-dioxygenated cyclopentenone derivatives through base-catalyzed rearrangement of pyranones followed by dynamic kinetic resolution. Milder conditions than previously reported for this rearrangement have been found regarding amine base catalysis, solvent and temperature effects. All data supports a mechanism involving cyclization of an intermediate formed by electrocyclic ring opening of a pyranone-derived enol. We have developed conditions for asymmetric synthesis of trans-4-tert-butoxy-5-hydroxycyclopent-2- enone, in 81% yield and 95% ee, and analogous dioxygenated cyclopentenones, via a lipase induced dynamic kinetic resolution.
De novo asymmetric bio- and chemocatalytic synthesis of saccharides - Stereoselective formal O-glycoside bond formation using palladium catalysis
Comely, Alex C.,Eelkema, Rienk,Minnaard, Adriaan J.,Feringa, Ben L.
, p. 8714 - 8715 (2007/10/03)
A novel integrated bio- and chemocatalytic approach to the de novo catalytic asymmetric synthesis of saccharides has been developed. Acetoxypyranones obtained enantiopure by enzymatic resolution have been shown to undergo highly stereoselective palladium-catalyzed formal O-glycoside bond formation. The combination of these protocols can be applied to the iterative asymmetric catalytic synthesis of saccharides. Copyright
Studies toward the synthesis of natural and unnatural dienediynes. Part 2: A practical approach to functionalised cyclopentenones
Caddick,Khan,Frost,Smith,Cheung,Pairaudeau
, p. 8953 - 8958 (2007/10/03)
The dienediyne natural products contain a functionalised dihydroxylated cyclopentane motif. A critical evaluation of the methods for the preparation and rearrangements of pyranones to give 4,5-dihydroxylated cyclopentenones is presented. (C) 2000 Elsevier Science Ltd.
Montmorillonite K-10 clay catalysed glycosidation of 1-O-acetyl-2,3-dideoxy-DL-pent-2-enopyrano-4-ulose
Shanmugam,Nair
, p. 3007 - 3013 (2007/10/03)
The O-glycosidation reaction of 1-O-acetyl-2,3-dideoxy-DL-pent-2-enopyran-4-ulose catalysed by the environmentally accepted and inexpensive industrial catalyst Montmorillonite K-10 clay with variety of alcohols in high yield is reported.
Synthesis of 6-Acyloxy and 6-Alkoxy Derivatives of 2H-Pyran-3(6H)-ones
Constantinou-Kokotou, Violetta,Kokotos, George,Georgiadis, Minas P.
, p. 151 - 154 (2007/10/02)
The 6-hydroxy-2H-pyran-3(6H)-ones 1a-d are esterified stereoselectively with acetic and formic acid, and with several amino acids and peptide derivatives using the DCC/DMAP method.The direct synthesis of the 6-alkxy derivatives 3g-k is also studied.
Total synthesis of 4-(D-alanylamino)-2-amino-2,3,4-trideoxy-DL-threo-pentose (3-deoxy-DL-prumycin)
Constantinou-Kokotou,Couladouros,Georgiadis,Kokotos,Georgiadis
, p. 163 - 172 (2007/10/02)
3-Deoxy-DL-prumycin (1) was synthesized from 2-furanmethanol (2-furfuryl alcohol, 2) in eleven steps in 15% total yield. Michael addition of azide anion to 2,3-dideoxy-DL-pent-2-enopyranos-4-ulose (3) and reduction in situ of the adduct afforded the key i
IMPROVED PROCEDURE FOR THE SYNTHESIS OF 6-ALKOXY-2,3-DIHYDRO-6H-PYRAN-3-ONES (2,3-DIDEOXY-DL-PENT-2-ENOPYRANOS-4-ULOSES). NEAT CONVERSION INTO POLYFUNCTIONALIZED CYCLOPENTENONES.
Mucha, Bernd,Hoffmann, H.Martin R.
, p. 4489 - 4492 (2007/10/02)
The glycosidic bond of 6-alkoxy-2,3-dihydro-6H-pyran-3-ones (3) is made advantageously in the presence of catalytic ZnCl2*etherate.A palladium-assisted transformation of 3 affords trans-4-alkoxy-5-hydroxy-2-cyclopenten-1-ones (4) in good yield.
