317834-47-2Relevant academic research and scientific papers
From Furan-Yne Systems to para -Benzoquinone Derivatives: Gold-Catalyzed Cyclization and Oxidation, and Further Reduction by Sodium Dithionate
Ahmadi, Saman,Ghanbari, Mohammad
, p. 775 - 784 (2020/10/13)
A series of furan-yne systems were transformed into the corresponding para -benzoquinone derivatives by gold(ΙΙΙ) catalyst. The two-step procedure consisted of a phenol synthesis and subsequent oxidation with iodobenzene diacetate. The reactions can be carried out in a one-pot procedure with the same precatalyst. The para -benzoquinone could simply be converted into the corresponding hydroquinones by reduction with sodium dithionate. This protocol features high efficiency, mild conditions, and wide substrate scopes.
Water Can Accelerate Homogeneous Gold Catalysis
Hashmi, A. Stephen K.,Rudolph, Matthias,Stein, Philipp M.
supporting information, p. 4264 - 4271 (2021/08/03)
A selection of gold-catalyzed reactions was examined in a kinetic study on the influence of water on the rate constant. Two intramolecular reactions and one intermolecular reaction, which proceed via proton transfer and/or protodeauration steps, were inve
Gold(I)-Catalyzed Reactivity of Furan-ynes with N-Oxides: Synthesis of Substituted Dihydropyridinones and Pyranones
Maranzana, Andrea,Marra, Francesco,Nejrotti, Stefano,Prandi, Cristina,Priola, Emanuele
supporting information, p. 8295 - 8307 (2021/07/02)
The reactivity of "furan-ynes"in combination with pyridine and quinoline N-oxides in the presence of a Au(I) catalyst, has been studied, enabling the synthesis of three different heterocyclic scaffolds. Selective access to two out of the three possible products, a dihydropyridinone and a furan enone, has been achieved through the fine-tuning of the reaction conditions. The reactions proceed smoothly at room temperature and open-air, and were further extended to a broad substrate scope, thus affording functionalized dihydropyridinones and pyranones.
Gold(I) Complexes with Eight-Membered NHC Ligands: Synthesis, Structures and Catalytic Activity
Cervantes-Reyes, Alejandro,Rominger, Frank,Rudolph, Matthias,Hashmi, A. Stephen K.
supporting information, p. 2523 - 2533 (2020/05/06)
A series of expanded-ring NHC gold complexes of the formula (NaphtDHD?Ar)Au?X (NaphtDHD=4,5-dihydro-1H-naphtho[1,8-ef][1,3]diazocin-3(2H)-ylidene; Ar: Mes=2,4,6-trimethylphenyl, Dipp=2,6-diisopropylphenyl or Xyl=2,6-dimethylphenyl; X=Cl, NCCH3, NTf2) have been synthesized, including the first gold(I) triflimidate complex (5) stabilized by an eight-membered NHC ligand. The new organogold compounds have been characterized by mass spectrometry, IR spectroscopy, and 1H and 13C NMR spectroscopy. The structural geometries of 3 b–c and 5 have been unequivocally established by crystallographic analysis revealing broad N-C-N angles (>121°) and high buried volume values (46–54%). The first catalytic studies were carried out on the cycloisomerization of 1,6-enynes, obtaining full conversions (0.5 mol% catalyst loading) and excellent endo/exo selectivity (up to 99:1), and on the gold-catalyzed phenol synthesis. Lastly, the (NaphtDHD-Dipp)Au+ NTf2? species was subjected to a kinetic experiment in the cyclization of a N-propargyl carboxamide to evaluate the efficiency of the pre-formed catalyst (5) and the in situ activated gold complex (3 b+AgNTf2). (Figure presented.).
Highly active phosphite gold(i) catalysts for intramolecular hydroalkoxylation, enyne cyclization and furanyne cyclization
Blanco Jaimes, Maria Camila,Rominger, Frank,Pereira, Mariette M.,Carrilho, Rui M. B.,Carabineiro, Sónia A. C.,Hashmi, A. Stephen K.
supporting information, p. 4937 - 4940 (2014/05/06)
New and highly active mononuclear phosphite gold(i) catalysts are described. Turn-over numbers up to 37-000 for the furan-yne reaction and up to 28-000-000 for the two-fold hydroalkoxylation of alkynes are reported.
Combining gold and palladium catalysis: One-pot access to pentasubstituted arenes from furan-yne and En-diyne substrates
Hashmi, A. Stephen K.,Ghanbari, Mohammad,Rudolph, Matthias,Rominger, Frank
supporting information; experimental part, p. 8113 - 8119 (2012/08/28)
A series of furan-yne systems was transformed into the corresponding tetrasubstituted annelated phenol derivatives that bear one bromo group. The two-step procedure consisted of a phenol synthesis and a subsequent electrophilic bromination with N-bromosuccinimide (NBS). The reactions can be performed in a one-pot procedure with the same precatalyst. The halogenation reaction is highly selective only in the presence of the gold catalyst. En-diyne substrates were also suitable starting materials; then the pentasubstituted aromatic core showed a completely different substitution pattern for the phenolic products. Furthermore, a one-pot protocol that consisted of a gold-catalyzed phenol synthesis, a gold-catalyzed halogenation reaction, and a palladium-catalyzed Suzuki coupling was established. The overall efficiency of this procedure was excellent and the substrate scope of the reaction was broad. Copyright
Heterogeneous gold-catalysed synthesis of phenols
Carrettin, Silvio,Blanco, M. Carmen,Corma, Avelino,Hashmi, A. Stephen K.
, p. 1283 - 1288 (2007/10/03)
Nanoparticles of gold supported on nanocrystalline CeO2 catalyse the isomerisation of ω-alkynylfurans to phenols. Initial leaching of gold was observed, which could be minimised by calcining. Subsequent runs showed that once all soluble species
