110-64-5Relevant articles and documents
Strohmeier,Gruenter
, p. C45,C47 (1975)
Ultra-Small Platinum Nanoparticles with High Catalytic Selectivity Synthesized by an Eco-friendly Method Supported on Natural Hydroxyapatite
Gama-Lara,Natividad,Vilchis-Nestor,López-Casta?ares, Rafael,García-Orozco,Gonzalez-Pedroza, María G.,Morales-Luckie, Raúl A.
, p. 3447 - 3453 (2019)
Abstract: The biosynthesis of Pt-nanoparticles (Pt NPs) supported on bovine bone powder was conducted by an environmentally friendly method that consists on immersing bovine bone powder into a Pt4+ metal ion solution at room temperature, atmospheric pressure and subsequent reduction by Heterotheca inuloides. It is worth pointing out that a calcination process is not required for the synthesis of this catalyst by the method reported herein. The nanocomposite was characterized by transmission electron microscopy (TEM), which revealed uniformly dispersed platinum nanoparticles with quasi-spherical form and average particle size of 7.1?nm. The XPS studies exhibited the presence of 47.62% Pt° and 51.84% PtO. The catalyst activity was tested in the selective hydrogenation of 2-butyne-1,4-diol towards 2-butene-1,4-diol. The nanocomposite exhibits a reasonable catalytic performance with nearly 100% conversion of the alkyne and 96% selectivity towards 2-butene-1,4-diol. Graphic Abstract: [Figure not available: see fulltext.].
Ammonium-tagged ruthenium-based catalysts for olefin metathesis in aqueous media under ultrasound and microwave irradiation
Gu?ajski, ?ukasz,Tracz, Andrzej,Urbaniak, Katarzyna,Czarnocki, Stefan J.,Bieniek, Micha?,Olszewski, Tomasz K.
, p. 160 - 166 (2019)
The influence of microwave and ultrasonic irradiation on the performance of ammonium-tagged Ru-based catalysts in olefin metathesis transformations in aqueous media was studied. Differences in the catalytic activity in correlation with the nature of the present counter ion and the size of the N-heterocyclic carbene (NHC) ligand were revealed. The presented methodology allows for preparation of a variety of polar and non-polar metathesis products under environmentally friendly conditions.
Photovoltaic-driven organic electrosynthesis and efforts toward more sustainable oxidation reactions
Nguyen, Bichlien H.,Perkins, Robert J.,Smith, Jake A.,Moeller, Kevin D.
, p. 280 - 287 (2015)
The combination of visible light, photovoltaics, and electrochemistry provides a convenient, inexpensive platform for conducting a wide variety of sustainable oxidation reactions. The approach presented in this article is compatible with both direct and indirect oxidation reactions, avoids the need for a stoichiometric oxidant, and leads to hydrogen gas as the only byproduct from the corresponding reduction reaction.
The stereochemistry of solvolysis of an acyclic allylic epoxide
Boaz
, p. 15 - 16 (1995)
In contrast to solvolysis of cyclic allylic epoxides, the acid-catalyzed solvolyses of optically pure 1,2-epoxy-3-butene using water or alcohols show a high degree of inversion stereoselectivity.
Highly selective semi-hydrogenation of alkynes with a Pd nanocatalyst modified with sulfide-based solid-phase ligands
Huang, Lingqi,Hu, Kecheng,Ye, Ganggang,Ye, Zhibin
, (2021)
Soluble small molecular/polymeric ligands are often used in Pd-catalyzed semi-hydrogenation of alkynes as an efficient strategy to improve the selectivity of targeted alkene products. The use of soluble ligands requires their thorough removal from the reaction products, which adds significant extra costs. In the paper, commercially available, inexpensive, metallic sulfide-based solid-phase ligands (SPL8-4 and SPL8-6) are demonstrated as simple yet high-performance insoluble ligands for a heterogeneous Pd nanocatalyst (Pd@CaCO3) toward the semi-hydrogenation of alkynes. Based on the reactions with a range of terminal and internal alkyne substrates, the use of the solid-phase ligands has been shown to markedly enhance the selectivity of the desired alkene products by efficiently suppressing over-hydrogenation and isomerization side reactions, even during the long extension of the reactions following full substrate conversion. A proper increase in the dosage or a reduction in the average size of the solid-phase ligands enhances such effects. With their insoluble nature, the solid-phase ligands have the distinct advantage in their simple, convenient recycling and reuse while without contaminating the products. A ten-cycle reusability test with the SPL8-4/Pd@CaCO3 catalyst system confirms its well-maintained activity and selectivity over repeated uses. A mechanistic study with x-ray photoelectron spectroscopy indicates that the solid-phase ligands have electronic interactions with Pd in the supported catalyst, contributing to inhibit the binding and further reaction of the alkene products. This is the first demonstration of solid-phase ligands for highly selective semi-hydrogenation of alkynes, which show strong promise for commercial applications.
Cowie et al.
, p. 541 (1969)
Synthesis of diols from 1,2-epoxy-3-butene
Mel'nik,Srednev,Rybina,Meshechkina,Shevchuk,Danilova
, p. 201 - 204 (2007)
The catalytic hydration of 1,2-epoxy-3-butene was studied. The products of the reaction are 3-butenediol-1,2(BD-1,2) and 2-butenediol-1,4 (BD-1,4). It was shown that the formation of 2-butenediol-1,4 proceeds predominantly in a polar solvent medium in the presence of the catalytic system "nickel iodide (bromide)-tetraethylammonium iodide" at a temperature of 80°C. In the presence of inorganic acids, the main product is 3-butenediol-1,2. Nauka/Interperiodica 2007.
Continuous Flow Z-Stereoselective Olefin Metathesis: Development and Applications in the Synthesis of Pheromones and Macrocyclic Odorant Molecules**
Browne, Duncan L.,Colombel-Rouen, Sophie,Crévisy, Christophe,Curbet, Idriss,Mauduit, Marc,McBride, Tom,Morvan, Jennifer,Roisnel, Thierry
supporting information, p. 19685 - 19690 (2021/08/06)
The first continuous flow Z-selective olefin metathesis process is reported. Key to realizing this process was the adequate choice of stereoselective catalysts combined with the design of an appropriate continuous reactor setup. The designed continuous process permits various self-, cross- and macro-ring-closing-metathesis reactions, delivering products in high selectivity and short residence times. This technique is exemplified by direct application to the preparation of a range of pheromones and macrocyclic odorant molecules and culminates in a telescoped Z-selective cross-metathesis/ Dieckmann cyclisation sequence to access (Z)-Civetone, incorporating a serial array of continually stirred tank reactors.
Preparation method of N-(4-methylpyridine-3-yl) methyl carbamate
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Paragraph 0020; 0022; 0025; 0030; 0032; 0035; 0040; 0042, (2021/06/02)
The invention relates to the technical field of preparation methods of N-(4-methylpyridine-3-yl) methyl carbamate, and discloses preparation of potassium tert-butoxide and preparation of the potassium tert-butoxide by using potassium methoxide. According to the preparation method of the N-(4-methylpyridine-3-yl) methyl carbamate, a user uses the potassium methoxide to prepare the potassium tert-butoxide, so that the content of the potassium tert-butoxide is higher, the potassium tert-butoxide and the potassium methoxide are very similar in properties and functions, so that the cost is saved, the method for extracting a THT solvent by using 1, 4-dichlorobutene as a raw material is simple, and the method has the advantages that the use amount of the catalyst is small, the condition is mild, the extraction purity is high, so that the cost is reduced again; and the N-(4-methylpyridine-3-yl) methyl carbamate is obtained by catalyzing two high-purity raw materials through the catalyst carbonic acid diester and stirring, so that the preparation efficiency is improved, the purity of the prepared N-(4-methylpyridine-3-yl) methyl carbamate is improved, the over-high preparation cost of the N-(4-methylpyridine-3-yl) methyl carbamate is avoided, and the use of the user is facilitated.
