26198-79-8Relevant articles and documents
Telomerization of butadiene with L-arabinose and D-xylose in DMF: Selective formation of their monooctadienyl glycosides
Estrine, Boris,Bouquillon, Sandrine,Henin, Francoise,Muzart, Jacques
, p. 2914 - 2922 (2007/10/03)
Conditions to achieve the palladium-catalysed telomerization of butadiene with L-arabinose and D-xylose as telogens have been identified. With DMF as solvent, optimised ratios of substrate, reactants and catalytic system allowed the selective grafting of
Palladium-Catalyzed Methoxycarbonylation of 1,3-Butadiene: Catalysis and Mechanistic Studies
Beller, Matthias,Krotz, Andreas,Baumann, Wolfgang
, p. 517 - 524 (2007/10/03)
The palladium-catalyzed methoxycarbonylation of 1,3-butadiene to methyl 3-pentenoate has been studied. Intermediates of the proposed catalytic cycle were synthesized and the elementary steps of the reaction have been investigated in detail. It is shown th
Mechanistic studies on Pd-catalyzed telomerization and co-cyclization of butadiene: Amphiphilicity of bis-π-allylpalladium intermediate in the presence of phosphine ligand
Kiji, Jitsuo,Okano, Tamon,Nomura, Takaaki,Saiki, Kayoko,Sai, Torei,Tsuji, Jiro
, p. 1939 - 1945 (2007/10/03)
Pd-catalyzed reactions of butadiene, which proceed through a bis-π-allylpalladium intermediate, (η3,η3-C8H12)Pd (2), were performed in the presence of both a pronucleophile (aceto- or cyanoacetate) and an electrophile (benzaldehyde). Methyl aceto- or cyanoacetate and benzaldehyde reacted independently with 2 to give telomers 8 and the divinylsubstituted pyranes 9, respectively. In the case of methyl cyanoacetate, the co-cyclization of 2 with 2-cyano-3-phenylpropenoate (11) formed in situ also took place to afford the cyclohexane derivative 10. Namely, three kinds of amphiphilic additions of the C8-chain of 2 occurred to δ+H-Nuδ-, δ+C=Cδ- and δ+C=Oδ- simultaneously in a one-pot reaction The Pd-catalyzed reaction of allyl chloride, allyltributylstannane, methyl cyanoacetate, and benzaldehyde was undertaken under neutral conditions, expecting the amphiphilic reactions by the intermediacy of (η3-C3H5)2Pd (6) formed in situ. Allylation of both benzaldehyde and methyl cyanoacetate took place. Competitively amphiphilic bis-allylation of the polar double bond of 11 also occurred to form the 1,7-octadiene derivative 18. The mechanisms of both reactions can be explainable in terms of the amphiphilicity of the intermediates (2 and 6) in the presence of a phosphine ligand.
15-Membered macrocyclic triolefin: Role in recovering active palladium catalyst for the telomerization of butadiene with methanol
Estrine, Boris,Blanco, Belén,Bouquillon, Sandrine,Hénin, Fran?oise,Moreno-Ma?as, Marcial,Muzart, Jacques,Pena, Carolina,Pleixats, Roser
, p. 7055 - 7057 (2007/10/03)
The 15-membered macrocyclic triolefin Ma stabilizes a Pd(0) catalyst, active and recyclable in telomerization of butadiene with methanol. This Pd catalyst is generated from different Pd(0) or Pd(II) sources associated with phosphanes.
Palladium-catalyzed reactions for the synthesis of fine chemicals, 14([≠]) control of chemo- and regioselectivity in the palladium-catalyzed telomerization of butadiene with methanol - Catalysis and mechanism
Vollmüller, Frank,Krause, Jochen,Klein, Susanne,M?gerlein, Wolfgang,Beller, Matthias
, p. 1825 - 1832 (2007/10/03)
The palladium-catalyzed telomerization reaction of butadiene with methanol has been examined with the aim of controlling the chemoselectivity (telomerization vs. dimerization products) and regioselectivity (linear vs. branched telomerization product) of the reaction. We have shown that the reaction temperature, ligand-to-metal ratio and ratio of substrates exert a large influence on the selectivity of the reaction. Selectivities of up to 97% for the desired linear telomerization product 1 can be achieved below 50 °C by employing both low PPh3/Pd and butadiene/methanol ratios. Mono(phosphane)palladium(0)-diallyl ether complexes, Ar3P- Pd[(CH2=CHCH2)2O] (5), serve as new catalysts for the reaction. In order to gain a mechanistic understanding of the observed selectivity effects, we synthesized the phosphane(octadienyl)palladium(II) complexes 7a and 9a as model compounds for key reaction intermediates and examined their stoichiometric reactions with the methoxide nucleophile. Based on our results, we propose an extension of the known telomerization mechanism that accounts for the observed selectivity effects.
Synthesis and Properties of (η3-1-Methylallyl)palladium(II) Formates as Models of Intermediates in the Palladium-Catalyzed Reductive Cleavage of Allylic Carboxylates and Carbonates with Formic Acid
Oshima, Masato,Sakamoto, Toshiaki,Maruyama, Yooichiroh,Ozawa, Fumiyuki,Shimizu, Isao,Yamamoto, Akio
, p. 453 - 464 (2007/10/03)
In order to gain insight into the mechanism of the regioselective formation of alkenes in the palladium-catalyzed reductive cleavage of allylic carboxylates or carbonates with formic acid, two types of (η3-1-methylallyl)palladium formates (P1 and P2 types) have been prepared as simple models of catalytic intermediates. The P1 type is a neutral complex coordinated with one tertiary phosphine ligand and a formato ligand: [Pd(η3-MeCHCHCH2)(O2CH)(L)] (L = PMePh2, PMe2Ph, PMe3, P(o-tolyl)3); the P2 type is a cationic complex bearing two tertiary phosphine ligands and a formate counter anion: [Pd(η3-MeCHCHCH2)L2]+CO2H- (L = PMePh2, PMe2Ph, PMe3). The structures and dynamic behavior of the complexes in solution have been examined in detail by NMR spectroscopy. Studies on the thermolysis of the P1 and P2-type complexes have clearly provided the following mechanistic viewpoints: (1) 1-butene and 2-butene are formed from the P1 species; (2) butadiene is liberated from the P2 species; (3) the ratio of 1-butene to 2-butene increases as the bulkiness of phosphine ligand increases. A mechanism involving two geometrical isomers of [Pd(η3-MeCHCHCH2)(H)(L)], which are formed by decarboxylation of the P1-type complexes, has been proposed for the formation of butenes.
Nickel(0) and palladium(0) complexes with 1,3,5-triaza-7-phosphaadamantane. Catalysis of buta-1,3-diene oligomerization or telomerization in an aqueous biphasic system
Cermak, Jan,Kvicalova, Magdalena,Blechta, Vratislav
, p. 355 - 363 (2007/10/03)
New homoleptic nickel(0) and palladium(0) complexes with a water-soluble ligand, 1,3,5-triaza-7-phosphaadamantane, were prepared and characterized by 1H, 13C, and 31P NMR spectra. The complexes, together with the known ana
DIMERISATION DE DIENES CONJUGUES A L'AIDE DE COMPLEXES DU NICKEL EN PRESENCE DE LIGANDS DE TYPE AMINOPHOSPHINITE ETUDE D'OPTIMISATION
Masotti, Henriette,Pfeiffer, Gilbert,Siv, Chhan,Courbis, Pierre,Sergent, Michelle,Phan TAN LUU, Roger
, p. 63 - 77 (2007/10/02)
New chiral aminophosphinite ligands are readily prepared and their behaviour as homogeneous catalysts was investigated in the linear dimerization of butadiene and isoprene.This latter reaction has been optimised using experimental research methodology, leading to a conversion rate above 50percent.
TELOMERIZATION OF AMINO ACIDS WITH BUTADIENE, CATALYZED BY PALLADIUM COMPLEXES
Dzhemilev, U. M.,Fakhretdinov, R. N.,Telin, A. G.
, p. 1447 - 1456 (2007/10/02)
The telomerization of α, β, γ, and ε-amino acids having various structures with butadiene under the influence of the three-component palladium catalyst Pd(acac)2-PPh3-AlEt3 was investigated in DMSO-toluene solution.The α and ε-aliphatic and also the α, β, and γ-aromatic amino acids react with butadiene, giving the products from octadienylation at the amino group exclusively.Under the conditions of telomerization aliphatic β-amino acids are cleaved with the formation of unsaturated tertiary amines. in the case of aliphatic γ-amino acids it is possible to obtain telomers alkylated at the carbonyl group.
