70353-99-0Relevant academic research and scientific papers
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 (2020/12/09)
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
scheme or table, p. 1071 - 1073 (2012/04/17)
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.
Oxidative addition of benzyliminium tetraphenylborate to Pd(dba)(dppe): Synthesis and catalytic activity of [(dppe)Pd(dba)-{η1(N)-PhCH2N=CMe2}] (BPh4)2
Aresta, Michele,Dibenedetto, Angela,Amodio, Eliana,Tommasi, Immacolata
, p. 2188 - 2193 (2007/10/03)
The synthesis and catalytic activity of the new dicationic Pd11 complex [(dppe)Pd(dba){η1(N)-PhCH2N=CMe2}] (BPh4)2 from the Pd0 complex Pd(dba)(dppe) and [(PhCH2)HN= CMe2]BPh4 are described. [(PhCH2)HN=CMe2]BPh4 adds to Pd(dba)(dppe) under mild conditions through a selective N-H activation. The resulting species further reacts with [(PhCH2)HN=CMe2]BPh4 and generates N-benzyl-N-isopropylamine and [(dppe)Pd(dba){η1(N)-PhCH2N= CMe2}](BPh4)2. The latter catalyzes the dimerization of methyl acrylate (MA) and the co-oligomerization of MA with styrene. Significant changes of the selectivity in the dimerization of MA have been found, e.g. changing the solvent from methyl acrylate (mostly tail-to-tail, T-T, coupling) to the ionic liquid [bmim]BF4 (T-T and head-to-tail, H-T, coupling). Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
CC-KUPLUNGEN VON CO2 MIT 1,3-DIENEN AN EISEN(0)-KOMPLEXEN; CARBOXYLATBILDUNG UND FOLGEREAKTIONEN
Hoberg, Heinz,Jenni, Klaus
, p. 193 - 202 (2007/10/02)
1,3-Dienes react with CO2 at ligand-iron(0) systems to η3-allyl carboxylates.The dynamic allylic system is influenced by addition of further ligands such as phosphanes or maleic acid anhydride or acetic acid anhydride.The direction of this infl
