1501-06-0Relevant articles and documents
1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU): A powerful catalyst for the Michael addition reaction of β-ketoesters to acrylates and enones
Muthusamy, Sengodagounder,Babu, Srinivasarao Arulananda,Gunanathan, Chidambaram
, p. 3247 - 3254 (2002)
The Michael addition reaction of 1,3-dicarbonyl compounds and enones was carried out in the presence of a catalytic amount of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in ethanol under the mild reaction condition furnished Michael adducts in excellent yield.
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Wheeler,De Rodriguez
, p. 1227 (1964)
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High-pH value chrome tanning aid containing polyfunctional group structure as well as preparation method and application thereof
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Paragraph 0035-0041; 0079, (2021/05/12)
The invention discloses a high-pH value chrome tanning aid containing a polyfunctional group structure as well as a preparation method and application thereof. The structure of the aid is a polyfunctional group compound containing ketone carboxylic ester. The invention discloses a preparation method of a high-pH value chrome tanning aid and a high-pH value chrome tanning application process. The chrome tanning aid structurally contains keto-carbonyl and carboxylic ester structures, and the keto-carbonyl and carboxylic ester structures react with arginine in collagen under the alkaline condition, so that collagen modification is achieved; carboxylic ester is hydrolyzed to generate carboxyl (-COOH), the number of collagen side chain carboxyl is increased, coordination sites with trivalent chromium are increased, high absorption of the chrome tanning agent is achieved, the concentration of trivalent chromium in chrome tanning wastewater is reduced, environmental pollution of the leather industry is reduced, and clean production of the leather industry is promoted; the method is easy to operate, and a new thought is provided for research of the high-pH value chrome tanning aid.
Five Roads That Converge at the Cyclic Peroxy-Criegee Intermediates: BF3-Catalyzed Synthesis of β-Hydroperoxy-β-peroxylactones
Vil, Vera A.,Gomes, Gabriel Dos Passos,Ekimova, Maria V.,Lyssenko, Konstantin A.,Syroeshkin, Mikhail A.,Nikishin, Gennady I.,Alabugin, Igor V.,Terent'Ev, Alexander O.
, p. 13427 - 13445 (2018/11/02)
We have discovered synthetic access to β-hydroperoxy-β-peroxylactones via BF3-catalyzed cyclizations of a variety of acyclic precursors, β-ketoesters and their silyl enol ethers, alkyl enol ethers, enol acetates, and cyclic acetals, with H2O2. Strikingly, independent of the choice of starting material, these reactions converge at the same β-hydroperoxy-β-peroxylactone products, i.e., the peroxy analogues of the previously elusive cyclic Criegee intermediate of the Baeyer-Villiger reaction. Computed thermodynamic parameters for the formation of the β-hydroperoxy-β-peroxylactones from silyl enol ethers, enol acetates, and cyclic acetals confirm that the β-peroxylactones indeed correspond to a deep energy minimum that connects a variety of the interconverting oxygen-rich species at this combined potential energy surface. The target β-hydroperoxy-β-peroxylactones were synthesized from β-ketoesters, and their silyl enol ethers, alkyl enol ethers, enol acetates, and cyclic acetals were obtained in 30-96% yields. These reactions proceed under mild conditions and open synthetic access to a broad selection of β-hydroperoxy-β-peroxylactones that are formed selectively even in those cases when alternative oxidation pathways can be expected. These β-peroxylactones are stable and can be useful for further synthetic transformations.
Copper(II) triflate catalyzed amination and aziridination of 2-Alkyl substituted 1,3-dicarbonyl compounds
Ton, Thi My Uyen,Tejo, Ciputra,Tiong, Diane Ling Ying,Chan, Philip Wai Hong
experimental part, p. 7344 - 7350 (2012/06/16)
A method to prepare α-acyl-β-amino acid and 2,2-diacyl aziridine derivatives efficiently from Cu(OTf)2 + 1,10-phenanthroline (1,10-phen)-catalyzed amination and aziridination of 2-alkyl substituted 1,3-dicarbonyl compounds with PhI=NTs is described. By taking advantage of the orthogonal modes of reactivity of the substrate through slight modification of the reaction conditions, a divergence in product selectivity was observed. In the presence of 1.2 equiv of the iminoiodane, amination of the allylic C-H bond of the enolic form of the substrate, formed in situ through coordination to the Lewis acidic metal catalyst, was found to selectively occur and give the β-aminated adduct. On the other hand, increasing the amount of the nitrogen source from 1.2 to 2-3 equiv was discovered to result in preferential formal aziridination of the C-C bond of the 2-alkyl substituent of the starting material and formation of the aziridine product.
