2979-22-8Relevant articles and documents
Size selectivity of a copper metal-organic framework and origin of catalytic activity in epoxide alcoholysis
Jiang, Dongmei,Urakawa, Atsushi,Yulikov, Maxim,Mallat, Tamas,Jeschke, Gunnar,Baiker, Alfons
, p. 12255 - 12262 (2009)
{(Cu(bpy)(H2O)2(BF4)2(bpy)} (Cu-MOF; MOF = metal-organic framework; bpy = 4,4'-bipyridine), with a 3D-interpenetrated structure and saturated Cu coordination sites in the framework, possesses unexpectedly high a
Cr-MIL-101 encapsulated Keggin phosphotungstic acid as active nanomaterial for catalysing the alcoholysis of styrene oxide
Wee, Lik H.,Bonino, Francesca,Lamberti, Carlo,Bordiga, Silvia,Martens, Johan A.
, p. 1351 - 1357 (2014)
Mesoporous chromium-based terephthalate metal-organic framework (MIL-101) encapsulated Keggin phosphotungstic acid (HPW) [MIL-101(HPW)] was demonstrated to be an active heterogeneous catalyst for selective catalysis of the ring opening reaction of styrene
Sulfur and iron co-doped titanoniobate nanosheets: A novel efficient solid acid catalyst for alcoholysis of styrene epoxide at room temperature
Zhang, Lihong,Hu, Chenhui,Zhang, Junfeng,Cheng, Liyuan,Zhai, Zheng,Chen, Jing,Ding, Weiping,Hou, Wenhua
, p. 7507 - 7509 (2013)
Sulfur and iron co-doped titanoniobate nanosheets were prepared and evaluated in alcoholysis of styrene epoxide. The resultant co-doped catalyst exhibited excellent catalytic performance (yield of 99% with methanol as the nucleophile in only 1 h at room temperature) and may act as a promising candidate in many acid-catalyzed reactions.
Thermal transformation of a layered multifunctional network into a metal-organic framework based on a polymeric organic linker
Silva, Patricia,Vieira, Fabiana,Gomes, Ana C.,Ananias, Duarte,Fernandes, Jose A.,Bruno, Sofia M.,Soares, Rosario,Valente, Anabela A.,Rocha, Joao,Paz, Filipe A. Almeida
, p. 15120 - 15138 (2011)
The preparation of layered [La(H3nmp)] as microcrystalline powders from optimized microwave-assisted synthesis or dynamic hydrothermal synthesis (i.e., with constant rotation of the autoclaves) from the reaction of nitrilotris(methylenephosphonic acid) (H6nmp) with LaCl 3?7H2O is reported. Thermogravimetry in conjunction with thermodiffractometry showed that the material undergoes a microcrystal-to-microcrystal phase transformation above 300 °C, being transformed into either a three-dimensional or a two-dimensional network (two models are proposed based on dislocation of molecular units) formulated as [La(L)] (where L3- = [-(PO3CH2) 2(NH)(CH2PO2)O1/2-]n 3n-). The two crystal structures were solved from ab initio methods based on powder X-ray diffraction data in conjunction with structural information derived from 13C and 31P solid-state NMR, electron microscopy (SEM and EDS mapping), FT-IR spectroscopy, thermodiffractometry, and photoluminescence studies. It is shown that upon heating the coordinated H3nmp3- anionic organic ligand undergoes a polymerization (condensation) reaction to form in situ a novel and unprecedented one-dimensional polymeric organic ligand. The lanthanum oxide layers act, thus, simultaneously as insulating and templating two-dimensional scaffolds. A rationalization of the various steps involved in these transformations is provided for the two models. Photoluminescent materials, isotypical with both the as-prepared ([(La0.95Eu0.05) (H3nmp)] and [(La0.95Tb0.05)(H 3nmp)]) and the calcined ([(La0.95Eu0.05)(L)]) compounds and containing stoichiometric amounts of optically active lanthanide centers, have been prepared and their photoluminescent properties studied in detail. The lifetimes of Eu3+ vary between 2.04 ± 0.01 and 2.31 ± 0.01 ms (considering both ambient and low-temperature studies). [La(H3nmp)] is shown to be an effective heterogeneous catalyst in the ring opening of styrene oxide with methanol or ethanol, producing 2-methoxy-2-phenylethanol or 2-ethoxy-2-phenylethanol, respectively, in quantitative yields in the temperature range 40-70 °C. The material exhibits excellent regioselectivity to the β-alkoxy alcohol products even in the presence of water. Catalyst recycling and leaching tests performed for [La(H3nmp)] confirm the heterogeneous nature of the catalytic reaction. Catalytic activity may be attributed to structural defect sites. This assumption is somewhat supported by the much higher catalytic activity of [La(L)] in comparison to [La(H3nmp)].
Multi-functional metal-organic frameworks assembled from a tripodal organic linker
Vilela, Sergio M. F.,Ananias, Duarte,Gomes, Ana C.,Valente, Anabela A.,Carlos, Luis D.,Cavaleiro, Jose A. S.,Rocha, Joao,Tome, Joao P. C.,Almeida Paz, Filipe A.
, p. 18354 - 18371 (2012)
The reaction between (benzene-1,3,5-triyltris(methylene))triphosphonic acid (H6bmt) and lanthanide chlorides, under typical hydrothermal conditions (180 °C for 3 days) or using microwave heating (5 minutes above 150 °C), led to the isolation of
A copper-phosphonate network as a high-performance heterogeneous catalyst for the CO2 cycloaddition reactions and alcoholysis of epoxides
Ai, Jing,Min, Xue,Gao, Chao-Ying,Tian, Hong-Rui,Dang, Song,Sun, Zhong-Ming
, p. 6756 - 6761 (2017)
A novel 3D copper-phosphonate network, with the general formula Cu7(H1L)2(TPT)3(H2O)6, namely compound 1, has been synthesized using a rigid tetrahedral linker tetraphenylsilane tetrakis-4-
Photoluminescent metal-organic frameworks - Rapid preparation, catalytic activity, and framework relationships
Silva, Patricia,Ananias, Duarte,Bruno, Sofia M.,Valente, Anabela A.,Carlos, Luis D.,Rocha, Joao,Almeida Paz, Filipe A.
, p. 5576 - 5591 (2013)
An optimized microwave-assisted synthesis has been used to prepare an isotypical series of 3D Ln3+ metal-organic frameworks (MOFs) based on residues of 2,5-pyridinedicarboxylic (pydc), namely, [Ln2(pydc) 3(H2O)
Controllable construction of metal-organic polyhedra in confined cavities via in situ site-induced assembly
Kang, Ying-Hu,Yan, Ni,Gao, Zhen-Yu,Tan, Peng,Jiang, Yao,Liu, Xiao-Qin,Sun, Lin-Bing
, p. 5278 - 5282 (2017)
Poor dispersity and low stability are two predominant shortcomings hindering the applications of metal-organic polyhedra (MOPs). The confinement of MOPs in nanoscale cavities of mesoporous matrices is efficient in overcoming both shortcomings, while the i
Enhancement of catalytic activity by homo-dispersing S2O82–-Fe2O3 nanoparticles on SBA-15 through ultrasonic adsorption
Chu, Qingyan,Chen, Jing,Hou, Wenhua,Yu, Haoxuan,Wang, Ping,Liu, Rui,Song, Guangliang,Zhu, Hongjun,Zhao, Pingping
, p. 955 - 963 (2018)
Mesoporous superacids S2O82–-Fe2O3/SBA-15 (SFS) with active nanoparticles are prepared by ultrasonic adsorption method. This method is adopted to ensure a homo-dispersed nanoparticle active phase, large specific surface area and many acidic sites. Compared with bulk S2O82–-Fe2O3, Br?nsted acid catalysts and other reported catalysts, SFS with an Fe2O3 loading of 30% (SFS-30) exhibits an outstanding activity in the probe reaction of alcoholysis of styrene oxide by methanol with 100% yield. Moreover, SFS-30 also shows a more excellent catalytic performance than bulk S2O82–-Fe2O3 towards the alcoholysis of other ROHs (R = C2H5-C4H9). Lewis and Br?nsted acid sites on the SFS-30 surfaces are confirmed by pyridine adsorbed infrared spectra. The highly efficient catalytic activity of SFS-30 may be attributed to the synergistic effect from the nano-effect of S2O82–-Fe2O3 nanoparticles and the mesostructure of SBA-15. Finally, SFS-30 shows a good catalytic reusability, providing an 84.1% yield after seven catalytic cycles.
Particular Handedness Excess through Symmetry-Breaking Crystallization of a 3D Cobalt Phosphonate
Gao, Chao-Ying,Wang, Fei,Tian, Hong-Rui,Li, Lei-Jiao,Zhang, Jian,Sun, Zhong-Ming
, p. 537 - 539 (2016)
A 3D chiral cobalt phosphonate has been obtained from achiral precursors in the absence of chiral inducers. Remarkably, the bulk sample is largely enantio-enriched with particular handedness through symmetry-breaking crystallization in spite of multiple r
Cellulose sulfate: An efficient heterogeneous catalyst for the ring-opening of epoxides with alcohols and anilines
Chaudhary, Pooja,Deepa,Meena, Dhan Raj,Aalam, Mohd Jubair,Yadav, Geeta Devi,Singh, Surendra
supporting information, p. 1834 - 1846 (2021/05/10)
Cellulose sulfate was synthesized by esterification of α-cellulose with concentrated sulfuric acid at ?10°C in ethanol. Cellulose is mainly sulfated on 3-, 6- and 3, 6-positions of the cellulose. It acts as a heterogeneous catalyst for the ring-opening of epoxides with alcohols or anilines and the Friedel-Crafts reaction between N-benzylindole and crotonaldehyde at room temperature. Methanolysis of cyclic epoxides, styrene oxide, terminal aliphatic epoxides, and glycidyl ethers were carried out using the catalyst (0.4–6.8 mg/mmol of epoxide) and afforded the corresponding products in 53–97% isolated yields after 10 min–24 h. Cellulose sulfate was successfully recycled and reused up to 3 catalytic cycles for the ring-opening of styrene oxide with methanol.
Iodine-Initiated Dioxygenation of Aryl Alkenes Using tert-Butylhydroperoxides and Water: A Route to Vicinal Diols and Bisperoxides
Gao, Xiaofang,Lin, Jiani,Zhang, Li,Lou, Xinyao,Guo, Guanghui,Peng, Na,Xu, Huan,Liu, Yi
, p. 15469 - 15480 (2021/11/16)
An environment-friendly and efficient dioxygenation of aryl alkenes for the construction of vicinal diols has been developed in water with iodine as the catalyst and tert-butylhydroperoxides (TBHPs) as the oxidant. The protocol was efficient, sustainable, and operationally simple. Detailed mechanistic studies indicated that one of the hydroxyl groups is derived from water and the other one is derived from TBHP. Additionally, the bisperoxides could be obtained in good yields with iodine as the catalyst, Na2CO3 as the additive, and propylene carbonate as the solvent, instead.
