22007-56-3Relevant academic research and scientific papers
Method for preparing amino alcohol derivative
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Paragraph 0093; 0094; 0095, (2018/11/22)
The invention provides a method for preparing an amino alcohol derivative. The method is characterized in that substitution reaction is carried out on ester groups of dihydric alcohol carboxylic esteror polyhydric alcohol carboxylic ester to obtain the amino alcohol derivative, wherein the amidogen is derived into sulfonamido, and at least one carboxylic ester group remains. The method for preparing the amino alcohol derivative has the advantages that the raw materials are cheap and obtained easily, the use quantity of catalysts is low, the reaction condition is simple, and the selectivity ofproducts is high.
Vicinal Difunctionalization of Alkenes under Iodine(III) Catalysis involving Lewis Base Adducts
Aertker, Kristina,Rama, Raquel J.,Opalach, Julita,Mu?iz, Kilian
supporting information, p. 1290 - 1294 (2017/04/18)
The influence of a 2-pyridinyl substituent on the catalytic performance of aryl iodides as catalyst in iodine(III) chemistry was explored. An efficient Lewis base adduct between the pyridine nitrogen and the electrophilic iodine(III) center was identified and confirmed by X-ray analysis. This arrangement was shown to generate a kinetically competent superior catalyst structure for the catalytic dioxygenation of alkenes. It introduces the concept of Lewis base adduct formation as a kinetic factor in iodine(I/III) catalysis. (Figure presented.).
Mechanistically Driven Development of an Iron Catalyst for Selective Syn-Dihydroxylation of Alkenes with Aqueous Hydrogen Peroxide
Borrell, Margarida,Costas, Miquel
supporting information, p. 12821 - 12829 (2017/09/25)
Product release is the rate-determining step in the arene syn-dihydroxylation reaction taking place at Rieske oxygenase enzymes and is regarded as a difficult problem to be resolved in the design of iron catalysts for olefin syn-dihydroxylation with potential utility in organic synthesis. Toward this end, in this work a novel catalyst bearing a sterically encumbered tetradentate ligand based in the tpa (tpa = tris(2-methylpyridyl)amine) scaffold, [FeII(CF3SO3)2(5-tips3tpa)], 1 has been designed. The steric demand of the ligand was envisioned as a key element to support a high catalytic activity by isolating the metal center, preventing bimolecular decomposition paths and facilitating product release. In synergistic combination with a Lewis acid that helps sequestering the product, 1 provides good to excellent yields of diol products (up to 97% isolated yield), in short reaction times under mild experimental conditions using a slight excess (1.5 equiv) of aqueous hydrogen peroxide, from the oxidation of a broad range of olefins. Predictable site selective syn-dihydroxylation of diolefins is shown. The encumbered nature of the ligand also provides a unique tool that has been used in combination with isotopic analysis to define the nature of the active species and the mechanism of activation of H2O2. Furthermore, 1 is shown to be a competent synthetic tool for preparing O-labeled diols using water as oxygen source.
Aerobic Acetoxyhydroxylation of Alkenes Co-catalyzed by Organic Nitrite and Palladium
Chen, Xian-Min,Ning, Xiao-Shan,Kang, Yan-Biao
supporting information, p. 5368 - 5371 (2016/11/02)
An aerobic acetoxyhydroxylation of alkenes cooperatively catalyzed by organic nitrite and palladium at room temperature using clean and cheap air as the sole oxidant has been developed. Various vicinal diols, diacetoxyalkanes, and dihalogenoalkanes have been synthesized. The gram-scale synthesis has also been approached. Vicinal difluorination and dichlorolation products have also been achieved via this reaction.
Direct oxidative lactonization of alkenoic acids mediated solely by NaIO4: Beyond a simple oxidant
Kang, Yan-Biao,Chen, Xian-Min,Yao, Chuan-Zhi,Ning, Xiao-Shan
supporting information, p. 6193 - 6196 (2016/05/19)
Triflic acid-catalyzed direct oxidative lactonization of alkenoic acids mediated solely by NaIO4 without halogen salts is described. Sodium periodate works not only as an oxidant, but also as an active reagent and directly mediates the lactonization. A new cheap, green, and practical oxidative lactonization approach has been developed using NaIO4 as the sole reagent.
Iron-Catalyzed Dioxygenation of Alkenes and Terminal Alkynes by using (Diacetoxyiodo)benzene as Oxidant
Srinivas,Rawat, Vikas S.,Sreedhar, Bojja
supporting information, p. 3587 - 3596 (2016/01/25)
An iron-catalyzed syn-diacetoxylation of alkenes and 1,2-oxyacetoxylation of terminal alkynes has been developed using (diacetoxyiodo)benzene as oxidant. A broad range of internal and terminal alkenes, including electron-rich as well as electron-deficient alkenes, gave the desired products in good to excellent yields with high diastereoselectivity (up to >99:1 dr). In addition the high catalytic activity of iron catalysis for the 1,2-oxyacetoxylation of terminal alkynes is also reported. The roles of catalyst, oxidant and other reaction parameters were evaluated for activation of the unsaturated bond.
Triflic acid catalyzed oxidative lactonization and diacetoxylation of alkenes using peroxyacids as oxidants
Kang, Yan-Biao,Gade, Lutz H.
experimental part, p. 1610 - 1615 (2012/04/04)
A clean and efficient diacetoxylation reaction of alkenes catalyzed by triflic acid using commercially available peroxyacids as the oxidants has been developed. This method was also applied in oxidative lactonizations of unsaturated carboxylic acids in good to high yields.
Metal-free, organocatalytic syn diacetoxylation of alkenes
Zhong, Wenhe,Liu, Shan,Yang, Jun,Meng, Xiangbao,Li, Zhongjun
supporting information; experimental part, p. 3336 - 3339 (2012/08/29)
A novel method for the organocatalytic syn diacetoxylation of alkenes has been developed using aryl iodides as efficient catalysts. A broad range of substrates, including electron-rich as well as electron-deficient alkenes, are smoothly transformed by the new procedure, furnishing the desired products in good to excellent yields with high diastereoselectivity (up to >19:1 dr).
Investigation of the catalytic activity of an electron-deficient vanadium(IV) tetraphenylporphyrin: A new, highly efficient and reusable catalyst for ring-opening of epoxides
Taghavi, S. Abdolmanaf,Moghadam, Majid,Mohammadpoor-Baltork, Iraj,Tangestaninejad, Shahram,Mirkhani, Valiollah,Khosropour, Ahmad Reza,Ahmadi, Venus
experimental part, p. 2244 - 2252 (2011/10/03)
In this work, the catalytic activity of high-valent tetraphenylporphyrinatovanadium(IV) trifluoromethanesulfonate, [V IV(TPP)(OTf)2], in the nucleophilic ring-opening of epoxides is reported. This new V(IV) catalyst was used as an efficient catalyst for alcoholysis with primary (methanol, ethanol and n-propanol), secondary (iso-propanol) and tertiary alcohols (tert-butanol), hydrolysis and acetolysis of epoxides with acetic acid and also for the conversion of epoxides to 1,2-diacetates with acetic anhydride, conversion of epoxides to thiiranes with ammonium thiocyanate and thiourea, and for conversion of epoxides to acetonides with acetone. The catalyst was reused several times without loss of its activity.
The nature of the catalytically active species in olefin dioxygenation with PhI(OAc)2: Metal or proton?
Kang, Yan-Biao,Gade, Lutz H.
supporting information; experimental part, p. 3658 - 3667 (2011/05/03)
Evidence for the protiocatalytic nature of the diacetoxylation of alkenes using PhI(OAc)2 as oxidant is presented. Systematic studies into the catalytic activity in the presence of proton-trapping and metal-complexing agents indicate that protons act as catalysts in the reaction. Using triflic acid as catalyst, the selectivity and reaction rate of the conversion is similar or superior to most efficient metal-based catalysts. Metal cations, such as Pd(II) and Cu(II), may interact with the oxidant in the initiation phase of the catalytic transformation; however, 1 equiv of strong acid is produced in the first cycle which then functions as the active catalyst. Based on a kinetic study as well as in situ mass spectrometry, a mechanistic cycle for the proton-catalyzed reaction, which is consistent with all experimental data presented in this work, is proposed.
