774-48-1Relevant articles and documents
Pillared cobalt-amino acid framework catalysis for styrene carbonate synthesis from CO2 and epoxide by metal-sulfonate-halide synergism
Kathalikkattil, Amal Cherian,Roshan, Roshith,Tharun, Jose,Soek, Han-Geul,Ryu, Hyeong-Seok,Park, Dae-Won
, p. 284 - 292 (2014)
The sulfonate anion is proposed as a remarkable partaker in catalyzing epoxide-CO2 cycloaddition for cyclic carbonate synthesis. The role is illustrated by the concerted action of a sulfonate-rich cobalt-amino acid framework catalyst [{Co(4,4′-bipy)(L-cys)(H2O)}×H 2O]n (2 D-CCB) and a quaternary ammonium bromide co-catalyst in synthesizing styrene carbonate (SC) at a turnover number of 228. SC yield at atmospheric pressure is presumed to result from the activation of CO2 by the sulfonate group. The involvement of SO3 - anions as basic sites in 2 D-CCB is ascertained from the initial rate (r0) for catalyzing Knoevenagel condensation reactions and by using CO2 temperature programmed desorption. Microwave pulses are used for synthesizing 2 D-CCB at a rate that is 288-fold faster than conventionally employed solvothermal methods. Unambiguous evidence for the pulsating role-play of sulfonate groups in 2 D-CCB is perceived by comparing the activity of an analogous metal organic framework (3 D-CCB) in which the sulfonate oxyanions are jammed by coordination with cobalt. 2 D-CCB is analyzed for heterogeneity, and reused four times. Copyright
Syntheses, characterization and reactivity of dinuclear ruthenium-nickel complexes with hexane-2,5-dione bis(thiosemicarbazonato) ligands
Fang, Duo-Wen,Jia, Ai-Quan,Dong, Xian-Ping,Xin, Zhifeng,Zhang, Qian-Feng
, p. 122 - 129 (2018)
Treatment of hexane-2,5-dione bis(thiosemicarbazones) ([CH3?C{= N?NH?C(=S)?NHR}?CH2]2, R = H, L1H2; CH3, L2H2?Me; CH2CH3, L3H2?Et; C6H5, L4H2?Ph) with nickel(II) acetate hydrate in refluxing ethanol gave a series of NiIIN2S2 metalloligands [Ni(L-R)] for the generation of hetero-bimetallic complexes. The reaction of equal mole each of [Ni(L1)], [Ni(L2?Me)], [Ni(L3?Et)], or [Ni(L4?Ph)] with [RuCl2(dmso)4] (dmso = dimethyl sulfoxide) at reflux resulted in isolation of neutral dinuclear ruthenium-nickel complexes [RuCl2{(Ni(L1)}(dmso)2] (1), [RuCl2{(Ni(L2?Me)}(dmso)2] (2), [RuCl2{(Ni(L3?Et)}(dmso)2] (3), and [RuCl2{(Ni(L4?Ph)}(dmso)2] (4). Interaction of [Ni(L-R)] with [CpRu(PPh3)2Cl] (Cp? = cyclopentadienyl) at room temperature led to formation of cationic dinuclear organoruthenium-nickel complexes [CpRu{(Ni(L1)}(PPh3)]Cl (5), [CpRu{(Ni(L2?Me)}(PPh3)]Cl (6), [CpRu{(Ni(L3?Et}(PPh3)]Cl (7), and [CpRu{(Ni(L4?Ph}(PPh3)]Cl (8). New bimetallic ruthenium-nickel complexes 1–8 have been characterized spectroscopically, of which molecular structures of three complexes [RuCl2{(Ni(L2?Me)}(dmso)2]·CH2Cl2 (2·CH2Cl2), [CpRu{(Ni(L2?Me)}(PPh3)]Cl?EtOH (6?EtOH), and [CpRu{(Ni(L3?Et}(PPh3)]Cl (7?H2O) have been established by single-crystal X-ray crystallography. Their catalytic activities for the acetalation of benzaldehyde in the presence of molecular H2 have been also investigated in this paper.
Metal nitrate-catalyzed one-pot oxidative esterification of benzaldehyde with hydrogen peroxide in alcoholic solutions at room temperature
Da Silva, Márcio José,De Oliveira, Cesar Macedo
, p. 3683 - 3691 (2021/03/03)
The activity of metal nitrate catalysts was investigated in the oxidative esterification reactions of benzaldehyde with hydrogen peroxide. Several types of metal nitrates (alkaline, alkaline earth, and transition metals) were evaluated as catalysts. Among the assessed salts, Fe(NO3)3 was the most efficient catalyst toward the formation of the target product (i.e., benzoic alkyl ester). In methyl alcohol, benzaldehyde was selectively oxidized to benzoic acid and then esterified to methyl benzoate. The efficiency of the catalyst was correlated with its higher Lewis acidity character, which was established through the pH measurements of methanolic solutions of the soluble metal nitrate salts. The influence of main variables of the reaction, such as catalyst load, temperature, and reactant stoichiometry, was investigated. The size of the carbon chain and steric hindrance played an essential role in the reaction selectivity. While methyl and ethyl alcohols selectively provided ester as the main product (ca. 70-75%) and acetal as the subproduct, the other alcohols gave ester, hemiacetal, and benzoic acid, which was formed in the least amount. The use of an inexpensive catalyst, a green oxidant, mild conditions, and short reaction times were the positive aspects of this one-pot process. The high TON (ca. 900) is evidence of the high catalytic activity of Fe(NO3)3. It is noteworthy that this methodology does not rely upon ligands and other additives.
Method for synthesizing 4-tert-butyl benzaldehyde
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Paragraph 0016; 0020-0022, (2020/02/19)
The invention discloses a method for synthesizing 4-tert-butyl benzaldehyde and belongs to the technical field of organic synthesis. The method comprises the steps of subjecting benzaldehyde and triorthoformate to a reaction to produce benzaldehyde acetal, then, subjecting the benzaldehyde acetal and isobutene to a sealed reaction in the presence of a catalyst, and carrying out acid quenching, thereby obtaining the 4-tert-butyl benzaldehyde. According to the method, the 4-tert-butyl benzaldehyde is obtained through adopting benzaldehyde protection, then, firstly, becoming an electron donatingorientating group, and then, prompting selective localization of the isobutene by employing an appropriate catalyst; and a ratio of a 2-tert-butyl benzaldehyde isomer to the product is smaller than 1:14, and after the reaction ends up, the process is applicable to industrialized large-scale production.
