15001-62-4Relevant academic research and scientific papers
Practical alternatives for the synthesis of β-iodofurans by 5-endo-dig cyclisations of 3-alkyne-1,2-diols
El-Taeb, Gamila M.M.,Evans, Ann B.,Jones, Simon,Knight, David W.
, p. 5945 - 5948 (2001)
Iodocyclisations of 3-alkyne-1,2-diols, obtained from acetylides and α-hydroxy-ketones or esters, give generally excellent yields of β-iodofurans by 5-endo-dig cyclisation followed by dehydration.
Sustainable Micellar Gold Catalysis - Poly(2-oxazolines) as Versatile Amphiphiles
Lempke, Linda,Ernst, Andrea,Kahl, Fabian,Weberskirch, Ralf,Krause, Norbert
supporting information, p. 1491 - 1499 (2016/05/19)
The application of five polymer amphiphiles in the gold-catalyzed allene cycloisomerizations under aqueous micellar conditions is described. The polymers were prepared by ring-opening cationic polymerization based on poly(2-methyl-2-oxazoline) as hydrophilic segment and different hydrocarbon- or fluorocarbon-based hydrophobic segments. The catalytic activity in the gold-catalyzed allene cyclization is strongly dependent on the type of gold precursor, the salt concentration in the bulk aqueous medium, and the concentration of the polymeric amphiphile. Best results were obtained with 2 mol% of gold(III) bromide, 1 mM of amphiphile and 5 M sodium chloride, affording over 80% yield for different heterocyclic products. The catalyst system is also suitable for the dehydrative cyclization of acetylenic diols to furans. Moreover, successful catalyst recycling was demonstrated in three consecutive runs when using optimized extraction conditions.
Leveraging the micellar effect: Gold-catalyzed dehydrative cyclizations in water at room temperature
Minkler, Stefan R. K.,Isley, Nicholas A.,Lippincott, Daniel J.,Krause, Norbert,Lipshutz, Bruce H.
supporting information, p. 724 - 726 (2014/03/21)
The first examples of gold-catalyzed cyclizations of diols and triols to the corresponding hetero- or spirocycles in an aqueous medium are presented. These reactions take place within nanomicelles, where the hydrophobic effect is operating, thereby driving the dehydrations, notwithstanding the surrounding water. By the addition of simple salts such as sodium chloride, reaction times and catalyst loadings can be significantly decreased.
Synthesis of furan-3-carboxylic and 4-methylene-4,5-dihydrofuran-3- carboxylic esters by direct palladium iodide catalyzed oxidative carbonylation of 3-yne-1,2-diol derivatives
Gabriele, Bartolo,Mancuso, Raffaella,Maltese, Vito,Veltri, Lucia,Salerno, Giuseppe
, p. 8657 - 8668 (2012/11/07)
A variety of 3-yne-1,2-diol derivatives 1, bearing a primary or secondary alcoholic group at C-1, have been efficiently converted into high value added furan-3-carboxylic esters 2 in one step by PdI2/KI-catalyzed direct oxidative carbonylation, carried out in alcoholic media under relatively mild conditions (100 °C under 40 atm of a 4/1 mixture of CO and air). Carbonylated furans 2 were obtained in fair to excellent isolated yields (56-93%) through a sequential 5-endo-dig heterocyclization-alkoxycarbonylation- dehydration process, using only oxygen as the external oxidant. Under similar conditions, 2-methyl-3-yne-1,2-diols 3, bearing a tertiary alcoholic group, afforded 4-methylene-4,5-dihydrofuran-3-carboxylates 4 in satisfactory yields (58-70%).
On the highly stereoselective addition of lithio-acetylides to α-hydroxy-ketones
Dunford, Damian,Guyader, Mathilde,Jones, Simon,Knight, David W.,Hursthouse, Michael B.,Coles, Simon J.
, p. 2240 - 2242 (2008/09/19)
Addition of 2 equiv of a lithio-acetylide to an unprotected α-hydroxy ketone is extremely stereoselective in examples where the two ketone substituents are relatively large.
Synthesis of δ-lactones from 2-alkynyl epoxides and 4-alkynyl-1,3-dioxolan-2-ones by palladium catalysed carbonylation and conjugate nucleophilic addition
Knight, Julian G.,Ainge, Simon W.,Baxter, Carl A.,Eastman, Timothy P.,Harwood, Simon J.
, p. 3188 - 3190 (2007/10/03)
Synthesis of δ-lactones from 2-alkynyl epoxides and 4-alkynyl-1,3-dioxolan-2-ones by palladium catalysed carbonylation and conjugate nucleophilic addition was investigated. The stereocontrolled conjugate addition of nucleophiles to the electron deficient
