54965-55-8Relevant academic research and scientific papers
Preparation method for synthesis of phenolic ester through thiocarboxylic acid mediated visible light catalyzed phenol acylation reaction
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Paragraph 0079; 0080; 0112; 0113; 0114, (2018/07/30)
The invention discloses a preparation method for synthesis of phenolic ester through a thiocarboxylic acid mediated visible light catalyzed phenol acylation reaction. Thiocarboxylic acid compounds andphenol compounds are subjected to a site specific reaction under certain conditions to produce phenolic ester compounds, wherein the certain conditions are as follows: under the conditions of normaltemperature, normal pressure and visible light, K2CO3 is used as an alkaline catalyst, terpyridyl ruthenium dichloride hexahydrate is used as a photosensitizer and acetonitrile is used as a reaction solvent. Synthesis of phenolic ester under catalysis of visible light is realized, thiocarboxylic acid is used as an acylation reagent, and the site specific phenol esterification reaction is realizedefficiently under mild conditions of normal temperature, normal pressure and visible light. The method has mild reaction conditions, large substrate functional group tolerance, high applicability andhigh yield, and an efficient, reliable and economical preparation method is provided for synthesis of phenolic ester.
A recyclable CO surrogate in regioselective alkoxycarbonylation of alkenes: Indirect use of carbon dioxide
Gehrtz,Hirschbeck,Fleischer
supporting information, p. 12574 - 12577 (2015/08/06)
Herein, we report a Pd-catalysed alkoxycarbonylation of alkenes based on the use of a recyclable CO2 reduction product, the crystalline and air-stable N-formylsaccharin, as a CO surrogate. The carbonylation proceeds under ambient conditions in an exceptionally complementary regioselective fashion yielding the desired branched products from styrene derivatives and valuable linear esters from alkyl-substituted alkenes.
Ti/Ni-mediated inter- and intramolecular conjugate addition of aryl and alkenyl halides and triflates
Marquez, Irene R.,Miguel, Delia,Millan, Alba,Marcos, M. Luisa,De Cienfuegos, Luis Alvarez,Campana, Araceli G.,Cuerva, Juan M.
, p. 1529 - 1541 (2014/03/21)
In this work, we show that the unique combination of a nickel catalyst and Cp2TiCl allows the direct conjugate addition of aryl and alkenyl iodides, bromides, and to a lesser extent, chlorides and triflates to α,β-unsaturated carbonyls at room temperature, without requiring the previous formation of an organometallic nucleophile. The reaction proceeds inter- and intramolecularly with good functional group compatibility, which is key for the development of free protecting group methodologies. Carbo- and heterocycles of five- and six-membered rings are obtained in good yields. Moreover, some insights about the mechanism involved have been obtained from cyclic voltammetry, UV-vis, and HRTEM measurements.
Nickel-catalyzed reductive hydroesterification of styrenes using CO 2 and MeOH
Gonzalez-Sebastian, Lucero,Flores-Alamo, Marcos,Garcia, Juventino J.
, p. 8200 - 8207 (2013/02/22)
Complexes [(dippe)Ni(μ-H)]2 (A) (dippe = 1,2-bis-di- isopropylphosphino)ethane) and [(dtbpe)Ni(μ-H)]2 (B) (dtbpe = 1,2-bis-di-tert-butylphospino)ethane) catalyze the reductive hydroesterification of styrenes with the use of CO2 and MeOH. The latter acts as a hydrogen source and as an esterificating agent, to yield the corresponding branched and linear esters in moderate to good yields. In all of the studied reactions the linear esters were obtained in higher amounts than the branched ones. When the hydroesterification reaction was carried out using a stoichiometric metal/substrate ratio, the complexes [(P-P)Ni(CO)2] and [(P-P)Ni(CO3)] (P-P = dippe or dtbpe) were isolated and characterized by standard spectroscopic methods. Compounds [(dtbpe)Ni(CO) 2] and [(dtbpe)Ni(CO3)] were also fully characterized by single-crystal X-ray diffraction.
Quantitative structure-activity relationships of pine weevil antifeedants, a multivariate approach
Sunnerheim, Kerstin,Nordqvist, Anneli,Nordlander, Goeran,Borg-Karlson, Anna-Karin,Unelius, C. Rickard,Bohman, Bjoern,Nordenhem, Henrik,Hellqvist, Claes,Karlen, Anders
, p. 9365 - 9372 (2008/03/17)
Antifeedant activity of mainly phenylpropanoic, cinnamic, and benzoic acids esters was tested on the pine weevil, Hylobius abietis (L.). Of 105 compounds screened for activity, 9 phenylpropanoates, 3 cinnamates, and 4 benzoates were found to be highly active antifeedants. To understand the structure-activity relationships of these compounds, a multivariate analysis study was performed. A number of molecular and substituent descriptors were calculated and correlated to results from two-choice feeding tests with H. abietis. Three local models were developed that had good internal predictive ability. External test sets showed moderate predictivity. In general, low polarity, small size, and high lipophilicity were characteristics for compounds having good antifeedant activity.
Stereoselectivity control by oxaspiro rings during Diels-Alder cycloadditions to cross-conjugated cyclohexadienones: The syn oxygen phenomenon
Ohkata, Katsuo,Tamura, Yukiko,Shetuni, Brandon B.,Takagi, Ryukichi,Miyanaga, Wataru,Kojima, Satoshi,Paquette, Leo A.
, p. 16783 - 16792 (2007/10/03)
The diastereofacial selectivity operating in Diels-Alder additions involving spirocyclic cross-conjugated cyclohexadienones with dienes of varying reactivity has been investigated. The study has included the ether series 1a-c as well as the lactone/ketone pair 2a/2b. In all cases, the preferred [4+2] cycloaddition pathway consisted of bonding from that π-surface syn to the oxygen atom. 4-Substituted-4-methyl-2,5-cyclohexadienones (monocyclic systems) were also examined and found to undergo bond formation preferentially from the face bearing the more electron-withdrawing of the two groups at the 4 position. Kinetic parameters were determined for the cycloaddition of 1a and 2a to cyclopentadiene. The rate acceleration profile of solvents was in the order CF3CH2OH ? CH3CN～CH2Cl 2 for the production of 9a from 1a and CF3CH2OH ? CH2Cl2 > CH3CN for the production of 21a from 2a, respectively. This spread in polarity had no major impact on product distribution, a phenomenon also reflected in the behavior of 4-substituted-4-methyl-2,5-cyclohexadienones under comparable conditions. Theoretical assessment of these experimental facts was undertaken at the HF/6-31G* level. The facial selectivity is understandable in terms of the secondary interaction between the HOMO of the diene and LUMO of the dienophile as well as the effective hyperconjugation between the newly forming bond and the 4-anti-C-C σ-orbital due to the more electron-donating bond, as defined by the Cieplak model.
