695-06-7Relevant articles and documents
Calcium(II)- And Triflimide-Catalyzed Intramolecular Hydroacyloxylation of Unactivated Alkenes in Hexafluoroisopropanol
Qi, Chenxiao,Yang, Shengwen,Gandon, Vincent,Leb?uf, David
supporting information, p. 7405 - 7409 (2019/10/02)
We report an efficient intramolecular hydroacyloxylation of unactivated alkenes, offering a streamlined access to relevant γ-lactones, which features the utilization of either a calcium(II) salt or triflimide as a catalyst in hexafluoroisopropanol. This method could be applied to the synthesis of natural products and the late-stage functionalization of natural and bioactive molecules. Additionally, DFT computations were used to elucidate the twist of reactivity observed between the hydroamidation and hydroacyloxylation of unactivated alkenes regarding the formation of 5- and 6-membered rings.
W(OTf)6-Catalyzed Synthesis of Γ-Lactones by Ring Contraction of Macrolides or Ring Closing of Terminal Hydroxyfatty Acids in Ionic Liquid
Xie, Zhong-Yu,Deng, Jin,Fu, Yao
, p. 2332 - 2339 (2018/07/31)
γ-Lactones are an important class of fine chemical products and are widely used in perfumes, medicines, pesticides, dyes, and other fields. Herein, a new method for γ-lactones preparation based on ring contraction was developed. Starting from macrolides, W(OTf)6 was used to catalyze the ring-opening polymerization then depolymerization. The depolymerization step was not a common ring-closing process, and the carbon number of the ring was reduced one by one by rearrangement to form the most thermodynamically stable five-membered ring compounds. γ-Caprolactone (180 °C for 10 h) was obtained in a yield of 94 % when [EMIM]OTf was used as the solvent, and the yield of isolated product was up to 85 %. The interaction of various components and the reaction mechanism were studied by FTIR spectroscopy and 1H NMR spectroscopy, respectively. Furthermore, γ-lactones could be produced when the substrate was extended to terminal hydroxyfatty acids. Unexpectedly, the catalyst was poisoned by 1 equivalent of H2O added during the process and thus the yield decreased greatly. The reaction is green and simple, and proceeds in one pot with high atom economy (100 % for macrolides and with water as the only byproduct for terminal hydroxyfatty acid), which provides a promising approach to synthesizing γ-lactones.
Preparation method of gamma-caprolactone
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Paragraph 0036; 0037; 0038; 0045; 0046; 0047, (2017/08/28)
The invention provides a preparation method of gamma-caprolactone. The preparation method comprises the following steps of using at least one of 6-caprolactone, poly(epsilon-caprolactone) and 6-hydroxycaproic acid as a raw material and a Lewis acid as a catalyst, and carrying out rearrangement reaction under a condition that a reaction temperature is 50 to 250 DEG C, so that the gamma-caprolactone is obtained. According to the preparation method, through using the Lewis acid as the catalyst, the raw material is subjected to one-step conversion, so that the gamma-caprolactone can be obtained; the preparation method has the characteristics of simple process, easy purification, high yield, greenness, safety and the like, and is suitable for large-scale industrialized production.
1H-pyrrole-2,4-dicarbonyl-derivatives and their use as flavoring agents
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, (2015/03/03)
The present invention primarily relates to 1H-pyrrole-2,4-dicarbonyl-derivatives of Formula (I) wherein R1, R2, R3, Z. Z' and J are as defined in the description, to mixtures thereof and to the use thereof as flavoring agents. The compounds in accordance with the present invention are suitable for producing, imparting, or intensifying an umami flavor. The invention further relates to flavoring mixtures, compositions for oral consumption as well as ready-to-eat, ready-to-use and semifinished products, comprising an effective amount of the compound of Formula (I) or of a mixture of compounds of Formula (I) and to specific methods for producing, imparting, modifying and/or intensifying specific flavor impressions.
Imidazo[1,2-a]pyridine-ylmethyl-derivatives and their use as flavoring agents
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, (2015/03/03)
The present invention primarily relates to imidazo[1,2-a]pyridine-ylmethyl-derivatives of Formula (I) wherein R1, R2, X, W e J are as defined in the description, to mixtures thereof and to the use thereof as flavoring agents. The compounds in accordance with the present invention are suitable for producing, imparting, or intensifying an umami flavor. The invention further relates to flavoring mixtures, compositions for oral consumption as well as ready-to-eat, ready-to-use and semifinished products, comprising an effective amount of the compound of Formula (I) and to specific methods for producing, imparting, modifying and/or intensifying specific flavor impressions.
γ-valerolactone ring-opening and decarboxylation over SiO 2/Al2O3 in the presence of water
Bond, Jesse Q.,Martin Alonso, David,West, Ryan M.,Dumesic, James A.
experimental part, p. 16291 - 16298 (2011/12/02)
γ-Valerolactone (GVL) has been identified as a promising, sustainable platform molecule that can be produced from lignocellulosic biomass. The chemical flexibility of GVL has allowed the development of a variety of processes to prepare renewable fuels and chemicals. In the present work involving a combination of computational and experimental studies, we explore the factors governing the ring-opening of GVL to produce pentenoic acid isomers, as well as their subsequent decarboxylation over acid catalysts or hydrogenation over metal catalysts. The ring-opening of GVL has shown to be a reversible reaction, while both the decarboxylation and hydrogenation reactions are irreversible and kinetically controlled under the conditions studied (temperatures from about 500 to 650 K). The most significant contributor to lactone reactivity toward ring-opening is the size of the ring, with γ- lactones being more stable and less readily opened than δ- and ε-analogues. We have observed that the presence of either a C=C double bond or a lactone (which opens to form a C=C double bond) is necessary for appreciable rates of decarboxylation to occur. Olefinic acids exhibit higher rates of decarboxylation than the corresponding lactones, suggesting that the decarboxylation of alkene acids provides a lower energy pathway to olefin production than the direct decarboxylation of lactones. We observe lower rates of decarboxylation as the chain length of alkene acids increases; however, acrylic acid (3-carbon atoms) does not undergo decarboxylation at the conditions tested. These observations suggest that particular double bond configurations yield the highest rates of decarboxylation. Specifically, we suggest that the formation of a secondary carbenium ion in the β position leads to high reactivity for decarboxylation. Such an intermediate can be formed from 2- or 3-alkene acids which have at least four carbon atoms.
Synthesis of (±)-4-alkanolides from pent-4-enoic acid
Ugurchieva,Lozanova,Zlokazov,Veselovsky
experimental part, p. 657 - 659 (2009/05/16)
Synthesis of (±)-4-hexanolide, (±)-4-nonanolide, and (±)-4-dodecanolide, racemic forms of the insect signal substances, has been accomplished by cationic cyclization of pent-4-enoic acid and its amide in the key step.
SELECTIVE OXIDATION OF ORGANIC COMPOUNDS
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Page/Page column 22, (2008/06/13)
This invention relates to the selective oxidation of organic compounds. According to the invention organic compounds are selectively oxidized using a peracid or a source of peracid, a transition metal based heterogeneous catalysts and a borate or boric acid in the presence of water. Using the process of the present invention, both excellent conversion and product selectivity maybe obtained.
Cycloisomerization of olefinic carboxylic acids catalyzed by trifluoromethanesulfonic acid
Coulombel, Lydie,Dunach, Elisabet
, p. 153 - 160 (2007/10/03)
The trifluoromethanesulfonic acid-catalyzed cyclization of various differently substituted unsaturated carboxylic acids affords selectively substituted lactones in good yields. The reactions use 0.5 to 5% molar ratio of catalyst and can be run without solvent.
Deiodination of iodolactones by transfer hydrogenolysis using Raney nickel and 2-propanol
Mebane, Robert C.,Grimes, Kimberly D.,Jenkins, Summer R.,Deardorff, Jonathan D.,Gross, Benjamin H.
, p. 2049 - 2054 (2007/10/03)
Raney nickel in refluxing 2-propanol is an effective catalytic system for reducing iodolactones into their corresponding lactones.
