52392-64-0Relevant academic research and scientific papers
Preparation and catalytic evaluation of a palladium catalyst deposited over two-dimensional zeolite ITQ-2 modified with N-donor groups
?těpni?ka, Petr,K?e?ková, Pavlína,Semler, Miloslav,?ejka, Ji?í
, p. 571 - 576 (2014)
Two-dimensional zeolite ITQ-2 was reacted successively with (3-chloropropyl)triethoxysilane, 2-(N,N-diethylamino)ethylamine, and ammonia to give a support bearing the =Si(CH2)3NHCH 2CH2NEt2 groups at the surface. Subsequent treatment with palladium(II) acetate afforded an immobilized palladium catalyst 3, which was tested in the Heck coupling of n-butyl acrylate with bromobenzene to give n-butyl cinnamate (4). This (pre)catalyst, which acts as a source of active metal species for the reaction occurring in the liquid phase, showed good activity in N,N-dimethylformamide and N,N-dimethylacetamide at 150 °C. Reaction tests with different bases revealed a pronounced effect of the base additive on the course of the catalyzed process in terms of both the activity (yield of the coupling product) and selectivity [amount of n-butyl 3,3-diphenylacrylate (5) resulting from twofold arylation]. Among the hydrated bases, the best yields of 4 were obtained in reactions performed in the presence of CH3CO2Na·3H2O and Na 3PO4·12H2O, while that with Na 2CO3·10H2O furnished considerably worse results. The use of the respective anhydrous bases not only decreased the yield of 4 but also incited the formation of the unwanted doubly arylated product 5.
A comparative study of some Pd-catalysed Heck reactions in polar- and aqueous biphasic media
Williams,Lombard,Holzapfel
, p. 2077 - 2081 (2001)
A comparative study of some Pd-catalysed reactions was carried out making use of various ligands and catalyst precursors in polar polar/aqueous biphasic media, the results of which assist in the judicious selection of the appropriate reaction conditions f
Synthesis and activity evaluation of a FeCl2-promoted palladium hollow nano-sphere heterogeneous catalyst in Mizoroki–Heck coupling reactions
Abadi, Parvaneh Ghaderi-Shekhi,Hajian, Gelareh,Joshaghani, Mohammad,Nadri, Shirin,Rafiee, Ezzat
, p. 139 - 147 (2014)
A high-active, high-quality, and high-yield hollow Pd–PVP–Fe (palladium–poly(N-vinylpyrrolidone)–iron) nano-sphere catalyst with cubic structure was synthesized via a cheap method without using any support. This catalyst exhibited excellent catalytic activity in the Mizoroki–Heck reactions of less reactive chlorobenzene and some aryl bromides with n-butyl acrylate. The catalyst was fully characterized using SEM (scanning electron microscopy), EDX (energy dispersive X-ray spectroscopy), TEM (transmission electron microscopy), HRTEM (high resolution TEM), SAED (selected area electron diffraction) pattern, XRD (X-ray diffraction spectroscopy), FT-IR (Fourier transform infrared spectrophotometry), UV–Vis Spectrophotometry, Zeta sizer, and AAS (atomic absorption spectrometry). Effects of FeCl2·4H2O and PVP concentrations as well as their compatibility with palladium in the catalytic system were investigated. The catalytic property of the catalyst can be controlled by adjusting the proportion of Fe0, Pd0, and PVP concentration. The reused catalyst showed excellent activity as well as negligible leaching of the metal nanostructures into solution from the catalyst system.
A supported aqueous phase catalyst coating in micro flow Mizoroki-Heck reaction
Stouten, Stefan C.,Wang, Qi,No?l, Timothy,Hessel, Volker
, p. 2194 - 2198 (2013)
The application of a supported aqueous phase catalyst (SAPC) coating was investigated for the Mizoroki-Heck reaction in micro flow and favorably compared to the use of an SAPC in a batch system. In batch, an 83% yield was observed after 4 h at 180 °C with a catalyst loading of 0.4 mol %, while in flow a residence time of 2.9 min provided a 21% yield with only 0.01 mol % catalyst loading. In batch the SAPC could be re-used twice without any significant loss in yield, but further re-use was prevented due to problematic accumulation of an ammonium salt. In the micro flow system, this problem could be overcome by adding water to the product flow prior to cooling, allowing even more effective use of the catalyst.
Continuous microflow synthesis of butyl cinnamate by a Mizoroki-Heck reaction using a low-viscosity ionic liquid as the recycling reaction medium
Liu, Shifang,Fukuyama, Takahide,Sato, Masaaki,Ryu, Ilhyong
, p. 477 - 481 (2004)
A continuous microflow system was developed with efficient catalyst recycling for a Mizoroki-Heck reaction of iodobenzene with butyl acrylate, using a low-viscosity ionic liquid ([bmim]-NTf2) as the reaction medium. Using a CPC CYTOS Lab System
Palladium(0) deposited on PAMAM dendrimers as a catalyst for C-C cross coupling reactions
Borkowski, Tomasz,Subik, Pawel,Trzeciak, Anna M.,Wolowiec, Stanislaw
, p. 427 - 441 (2011)
PAMAM dendrimers of generations G2-G3 as well as a partially substituted derivative of generation G4 and a low-molecular-weight tricyclic ligand 4 were used to bind Pd(0) nanoparticles. The obtained adducts were tested as catalysts for C-C crosscoupling reactions, such as the Suzuki-Miyaura, Hiyama, Heck and Sonogashira reaction. The highest yields of the coupling product, diphenylacetylene, were obtained with all the catalysts studied in the Sonogashira coupling performed in ethanol with K2CO3 as base. Very good results, 85-100%, were also found in the Suzuki-Miyaura cross-coupling, while the efficiency of the Hiyama coupling appeared lower, with 38-52% of 2-Methylbiphenyl formed. In all reactions, the G2-Pd(0) catalyst, containing an unmodified dendrimer, afforded the highest yields of the cross-coupling products.
Comparison of activity and selectivity of various metal-TPPTS complex catalysts in ethylene glycol-toluene biphasic heck vinylation reactions of iodobenzene
Bhanage,Zhao,Shirai,Arai
, p. 9509 - 9512 (1998)
Heck vinylation reactions of iodobenzene were performed with various metal-TPPTS complexes and potassium acetate in a hipbasic mode using ethylene glycol and toluene. The activity, selectivity, stability and recycle performance of these catalytic systems,
Structure and Reactivity of "Unusual" N-Heterocyclic Carbene (NHC) Palladium Complexes Synthesized from Imidazolium Salts
Lebel, Helene,Janes, Marc K.,Charette, Andre B.,Nolan, Steven P.
, p. 5046 - 5047 (2004)
The reaction between palladium acetate and IMES·HCl leads to the formation of a novel palladium complex. The X-ray crystal structure analysis reveals that the palladium is C(2) bound to one NHC ligand (the normal binding mode), whereas the second ligand i
Pd-PVP colloid as catalyst for Heck and carbonylation reactions: TEM and XPS studies
Gniewek, Andrzej,Trzeciak, Anna M.,Ziolkowski, Jozef J.,Kepinski, Leszek,Wrzyszcz, Jozef,Tylus, Wlodzimierz
, p. 332 - 343 (2005)
Pd-PVP colloid (stabilized with polyvinylpyrrolidone) with a diameter of 19.8 nm in [Bu4N]Br medium catalyzes Heck coupling of bromobenzene with butyl acrylate and methoxycarbonylation of iodobenzene reactions. Oxidative addition of PhI or PhBr to Pd-PVP as the first step of a catalytic reaction was confirmed by TEM and XPS measurements. TEM studies showed significant reduction of Pd nanoparticle size after their reaction with PhX (X = I, Br) and [Bu 4N]X (X = Cl, Br, I). The biggest shift of the center of nanoparticle size distribution, from 19.8 nm to 7.6 nm, was found when Pd-PVP reacted with PhI and [Bu4N]Br. The formation of [Bu4N] 2[Pd(Ph)Br3]- and [Bu4N]2[PdBr 4]-type complexes in that system was evidenced by XPS and UV-vis spectra.
Benzyne-Mediated Esterification Reaction
Li, Yang,Shi, Jiarong,Zhao, Jinlong
supporting information, p. 7274 - 7278 (2021/10/01)
A benzyne-mediated esterification of carboxylic acids and alcohols under mild conditions has been realized, which is made possible via a selective nucleophilic addition of carboxylic acid to benzyne in the presence of alcohol. After a subsequent transesterification with alcohol, the corresponding esters can be produced efficiently. This benzyne-mediated protocol can be used on the modification of Ibuprofen, cholesterol, estradiol, and synthesis of nandrolone phenylpropionate. In addition, benzyne can also be used to promote lactonization and amidation reaction.
