115-22-0Relevant articles and documents
Synthesis and characterization of ZrO2 as acid-basic catalysts: Reactivity of 2-methyl-3-butyn-2-ol
Aramendia, M. Angeles,Borau, Victoriano,Jimenez, Cesar,Marinas, Jose M.,Marinas, Alberto,Porras, Andres,Urbano, Francisco J.
, p. 240 - 250 (1999)
Two ZrO2-based catalysts have been synthesized by thermal treatment of a gel prepared from ZrOCl2 · 8H2O. The effect of different preparation parameters on the final properties of the solids was studied. Textural characterization was carried out from nitrogen adsorption/desorption isotherms. XRD and FT-Raman spectroscopy have been used to elucidate the physical state of the catalysts. Their acid-base properties were studied following temperature programmed desorption-mass spectrometry and diffuse reflectance infrared Fourier transform techniques, by using pyridine, 2,6-dimethylpyridine and carbon dioxide as probe molecules. Both solids were tested for the 2-methyl-3-butyn-2-ol reaction by using two different procedures: (a) in a microcatalytic pulse reactor and (b) through isotherm and temperature programmed surface reactions in a flow reactor. In addition, temperature programmed oxidation and temperature programmed desorption experiments revealed that catalyst deactivation was caused by carbon deposition on the catalytic surface. Amphoteric selectivity for both solids, leading to 3-hydroxy-3-methyl-2-butanone and 3-methyl-3-buten-2-one, depends on the reaction temperature; thus, it is 92% at 225°C for a catalyst calcined at 400°C (ZrO2-400VAC).
A study of two thermostable NLO chromophores with different π-electron bridges using fluorene as the donor
Wang, Haoran,Liu, Fenggang,Yang, Yuhui,Zhang, Maolin,Peng, Chengcheng,Bo, Shuhui,Liu, Xinhou,Qiu, Ling,Zhen, Zhen
, p. 1038 - 1044 (2015)
Two chromophores C1 and C2 based on a fluorene electron donor with different π-electron bridges and the same electron acceptor have been synthesized and systematically characterized using NMR, MS and UV-vis absorption spectra. The energy gap between the ground state and the excited state and molecular nonlinearity were studied using UV-vis absorption spectroscopy, Density Functional Theory calculations and cyclic voltammetry measurements. The different properties between C1 and C2 were systematically compared. The results showed that C2 had a better performance than C1. The electrooptic coefficient of a poled film containing 25 wt% of C2 doped in amorphous polycarbonate afforded a value of 40 pm V-1 at 1310 nm. In addition, the excellent thermostability of C2 made itself a favourable candidate for practical application.
Hydrolysis of methylacetoin ethyl phosphate. competing pathways for carbonyl hydrate participation in a model for biotin carboxylation
Taylor, Scott D.,Kluger, Ronald
, p. 867 - 871 (1993)
Methylacetoin ethyl phosphate (1) is a phosphodiester with a carbonyl group β to phosphorus. The phosphate ester of a carbonyl hydrate, expected to be generated from an intramolecular reaction of 1 in base, is a model for an enzymic reaction intermediate which would form from the reaction of the tetrahedral addition production of biotin and bicarbonate with ATP. The hydrolysis of 1 is 104-105 times more rapid than that of dimethyl phosphate, extrapolated to common conditions (1 M NaOH, 55°C). Kinetic, product, and isotope labeling studies show that the hydrate of the carbonyl group of 1 serves as an intramolecular nucleophile toward phosphorus, forming the expected phosphate ester of the carbonyl hydrate through cyclic phosphorane intermediates. These adducts decompose by routes which parallel the proposed enzymic mechanism. In addition, solvent isotope incorporation reveals a route not found in reactions of carbonyl-substituted phosphotriesters: the conjugate base of the carbonyl hydrate acts an intramolecular nucleophile at the adjacent carbon atom, forming an unstable hydroxyoxirane (which becomes methylacetoin) and ethyl phosphate. An analogous reaction of ribonucleic acids (and RNAzymes) would have the 2′ hydroxyl group react at the 3′ carbon to form an oxyoxirane, cleaving the 3′ internucleotide bond.
An abnormal reaction of esters of 3-hydroxy-3-methylbutan-2-one. A rapid synthesis of bullatenone and geiparvarin
Villemin, Didier,Jaffres, Paul-Alain,Hachemi, Messaoud
, p. 537 - 538 (1997)
A new rapid and facile synthesis of two natural products with the structure of3(2H)furanone is described by a cyclisation catalysed by cesium fluoride.
Nonlinear optical chromophores based on Dewar's rules: Enhancement of electro-optic activity by introducing heteroatoms into the donor or bridge
Xu, Huajun,Yang, Dan,Liu, Fenggang,Fu, Mingkai,Bo, Shuhui,Liu, Xinhou,Cao, Yuan
, p. 29679 - 29688 (2015)
In this work, we investigated the enhancement of the electro-optic response by introducing electron-rich heteroatoms as additional donors into the donor or bridge of a conventional second-order nonlinear optical chromophore. A series of chromophores C2-C4 based on the same tricyanofuran acceptor (TCF) but with different heteroatoms in the alkylamino phenyl donor (C2 or C3) or thiophene bridge (C4) have been synthesized and systematically investigated. Density functional theory calculations suggested that chromophores C2-C4 had a smaller energy gap and larger first-order hyperpolarizability (β) than traditional chromophore C1 due to the additional heteroatoms. Single crystal structure analyses and optimized configurations indicate that the rationally introduced heteroatom group would bring larger β and weaker intermolecular interactions which were beneficial for translating molecular β into macro-electro-optic activity in electric field poled films. The electro-optic coefficient of poled films containing 25 wt% of these new chromophores doped in amorphous poly-carbonate afforded values of 83 and 91 pm V-1 at 1310 nm for chromophores C3 and C4, respectively, which are two times higher than that of the traditional chromophore C1 (39 pm V-1). High r33 values indicated that introducing heteroatoms to the donor and bridge of a conventional molecular structure can efficiently improve the electron-donating ability, which improves the β. The long-chain on the donor or bridge part, acting as the isolation group, may reduce inter-molecular electrostatic interactions, thus enhancing the macroscopic EO activity. These results, together with good solubility and compatibility with the polymer, show the new chromophore's potential application in electro-optic devices.
Ionic Liquid as an Efficient Promoting Medium for Fixation of CO 2: Clean Synthesis of α-Methylene Cyclic Carbonates from CO2 and Propargyl Alcohols Catalyzed by Metal Salts under Mild Conditions
Gu, Yanlong,Shi, Feng,Deng, Youquan
, p. 391 - 394 (2004)
Reactions of propargylic alcohols with CO2 in a [BMIm][PhSO 3]/CuCl catalytic system to produce the corresponding α-methylene cyclic carbonates were conducted with high yields. Mild reaction conditions, enhanced rates, improved yields, and recyclable ionic liquid catalyst systems are the remarkable features exhibited in this process. Furthermore, the use of large amounts of tertiary amines as well as nitrogen-containing organic solvent as employed in previously studies was avoided.
α-Oxidation of ketones using n-cation radicals
Schulz, Manfred,Kluge, Ralph,Sivilai, Li,Kamm, Birgit
, p. 2371 - 2380 (1990)
Six-membered ring ketones and acyclic ketones were oxidized by stable triarylamminium radical cations in moist acetonitrile at room temperature in the presence of a base to α-hydroxy ketones in good yield. Five-membered ring ketones gave the corresponding αβ-unsaturated compounds.
VOLATILE CONSTITUENTS OF PLUS AND MINUS STRAINS OF BLAKESLEA TRISPORA
Nabeta, K.,Nishimori, I.,Sato, S.,Sugisawa, H.
, p. 1133 - 1136 (1980)
Identification of the predominant constiutents produced by the plus and minus strains of Blakeslea trispora is described.The occurence of xylenes in the volatiles produced by the plus strain is reported.Additionally, production of 3-hydroxy-3-methylbutanal by the plus strain and dimethyl allyl alcohol by the minus strains were confirmed.Isoamyl alcohol, 1-octen-3-ol, 3-octanol and β-phenethyl alcohol were identified in volatiles from both strains. - Key Word Index: Blakeslea trispora; Mucorales, xylene; isoamyl alcohol; 3-hydroxy-3-methylbutanal; dimethyl allyl alcohol.
A green and recyclable CuSO4·5H2O/ionic liquid catalytic system for the CO2-promoted hydration of propargyl alcohols: an efficient assembly of α-hydroxy ketones
Chen, Cheng,Chen, Yiyun,Hu, Jia,Huang, Leilei,Verpoort, Francis,Wang, Yu,Yuan, Ye,Zhao, Yufeng,Zheng, Jiayun
, (2021/12/03)
α-Hydroxy ketones are important building blocks in biological, pharmaceutical and synthetic chemistry. In this work, diverse α-hydroxy ketones were efficiently constructed through the CO2-promoted hydration process of propargyl alcohols, which was catalyzed by a system consisted of economical CuSO4·5H2O and a green 1-butyl-3-methylimidazolium acetate ionic liquid. Particularly, this catalytic system exhibited excellent activity under atmospheric CO2 or even mimetic flue gas (20 vol% of CO2). Moreover, this system employed the lowest metal loading ever reported (0.004–0.25 mol%) meanwhile reached the highest turnover number (11700) for the target hydration reaction. Additionally, this is the first reported Cu catalytic system with reliable recyclability, which could be easily reused at least 6 times with yields higher than 85%.
A CO2-mediated base catalysis approach for the hydration of triple bonds in ionic liquids
Han, Buxing,Ke, Zhengang,Li, Ruipeng,Liu, Zhimin,Tang, Minhao,Wang, Yuepeng,Zeng, Wei,Zhang, Fengtao,Zhao, Yanfei
supporting information, p. 9870 - 9875 (2021/12/27)
Herein, we report a CO2-mediated base catalysis approach for the activation of triple bonds in ionic liquids (ILs) with anions that can chemically capture CO2 (e.g., azolate, phenolate, and acetate), which can achieve hydration of triple bonds to carbonyl chemicals. It is discovered that the anion-complexed CO2 could abstract one proton from proton resources (e.g., IL cation) and transfer it to the CN or CC bonds via a six-membered ring transition state, thus realizing their hydration. In particular, tetrabutylphosphonium 2-hydroxypyridine shows high efficiency for hydration of nitriles and CC bond-containing compounds under a CO2 atmosphere, affording a series of carbonyl compounds in excellent yields. This catalytic protocol is simple, green, and highly efficient and opens a new way to access carbonyl compounds via triple bond hydration under mild and metal-free conditions.
