1119-43-3Relevant articles and documents
H2-Free Re-Based Catalytic Dehydroxylation of Aldaric Acid to Muconic and Adipic Acid Esters
Ho?evar, Brigita,Pra?nikar, An?e,Hu?, Matej,Grilc, Miha,Likozar, Bla?
, p. 1244 - 1253 (2021)
As one of the most demanded dicarboxylic acids, adipic acid can be directly produced from renewable sources. Hexoses from (hemi)cellulose are oxidized to aldaric acids and subsequently catalytically dehydroxylated. Hitherto performed homogeneously, we present the first heterogeneous catalytic process for converting an aldaric acid into muconic and adipic acid. The contribution of leached Re from the solid pre-reduced catalyst was also investigated with hot-filtration test and found to be inactive for dehydroxylation. Corrosive or hazardous (HBr/H2) reagents are avoided and simple alcohols and solid Re/C catalysts in an inert atmosphere are used. At 120 °C, the carboxylic groups are protected by esterification, which prevents lactonization in the absence of water or acidic sites. Dehydroxylation and partial hydrogenation yield monohexenoates (93 %). For complete hydrogenation to adipate, a 16 % higher activation barrier necessitates higher temperatures.
Selective hydrogenation of trans,trans-muconic acid to adipic acid over a titania-supported rhenium catalyst
She, Xiaoyan,Brown, Heather M.,Zhang, Xiao,Ahring, Birgitte K.,Wang, Yong
, p. 1071 - 1073 (2011)
Metal oxide-supported rhenium catalysts are highly active and selective for the hydrogenation of trans,trans-muconic acid to adipic acid. High yields to adipic acid are achieved (ca. 88%) over Re/TiO2 catalyst at 210°C after 5h, using methanol as solvent. The selectivity of the rhenium-catalyzed hydrogenation of muconic acid to adipic acid may be further enhanced by using acetone or larger alcohols as solvent in comparison to methanol.
Syntheses and biological properties of brefeldin analogues
Foerster, Sebastian,Persch, Elke,Tverskoy, Olena,Rominger, Frank,Helmchen, Guenter,Klein, Christian,Goenen, Basak,Bruegger, Britta
experimental part, p. 878 - 891 (2011/04/26)
Total and partial syntheses of brefeldin analogues are described. (6R)-Hydroxy-BFA (5) was obtained through a total synthesis from (1S,2R)-2-[(trityloxy)methyl]cyclopent-3-ene-1-carbonitrile (cis-8) in 13 steps. The BFA lactam analogue 6 was prepared via
A stereoselective palladium-mediated reductive coupling of electron-deficient terminal iodoalkenes
Batsanov, Andrei S.,Knowles, Jonathan P.,Samsam, Benedict,Whiting, Andrew
supporting information; experimental part, p. 227 - 233 (2009/04/11)
Iodoacrylate esters undergo palladium-catalysed reductive homocoupling to derive dienyl diester derivatives. This reductive coupling can be extended to ester-substituted terminal iododienes to derive tetraene diesters. In all cases, the reactions show relatively high levels of stereocontrol, which shows an inversion of stereochemistry about one iodoalkene unit. This process, and the suggestion that the reaction releases diiodine, is consistent with a syn-1,2-addition of an iodopalladium(II)-alkene species across another iodoalkene unit (carbometallation step), followed by reductive syn-elimination of iodopalladium iodide to derive palladium(II) iodide. It appears that under the reaction conditions employed, palladium(II) iodide may equilibrate to palladium(O) and diiodine, which can be observed or trapped out from the reaction mixture.
An efficient synthesis of 3'-spiro sultone nucleosides functionalized on the sultone moiety via Pd-catalyzed cross-coupling reaction
Lobaton,Camarasa,Velazquez
, p. 1312 - 1314 (2007/10/03)
We describe the first efficient application of the Stille coupling reaction on iodo 3'-spiro sultone nucleosides. The yield and rate of the reaction are significantly affected by the addition of copper iodide as cocatalyst, AsPh3 as ligand and organostannane stoichiometry. Using this technology a number of alkenyl-, phenyl- and allyl-substituted 3'-spiro sultone nucleosides were produced.
An Efficient and Selective Pallladium-catalysed Oxidative Dicarbonylation of Akynes to Alkyl- or Aryl-maleic Esters
Gabriele, Bartolo,Costa, Mirco,Salerno, Giuseppe,Chiusoli, Gian Paolo
, p. 83 - 88 (2007/10/02)
Terminal alkyne dicarbonylation can be readily effected under mild conditions by treating alkynes with carbon monoxide and alcohols or water at 25-80 deg C in the presence of PdI2, KI and air, with unprecedented catalytic efficiency.Dicarbonylation products are mainly maleic esters or acids and their ring-chain tautomers.The latter are formed to a large extent at room temperature.Reaction pathways are discussed.
