19289-28-2Relevant academic research and scientific papers
Alkylation of active methylenes via benzhydryl cations
Bisaro, Fabrice,Prestat, Guillaume,Vitale, Maxime,Poli, Giovanni
, p. 1823 - 1826 (2002)
The acid mediated reaction between active methylenes and benzhydryl alcohols, or their derivatives, is reported. Ethyl acetoacetate, acetylacetone, and N,N-dibenzyl-malonamic acid methyl ester are benzhydrylated in quantitative yields in the presence of molar amounts of BF3·OEt2 in CH2Cl2 at r.t. TMSOTf and H2SO4 appear to be equally efficient. Use of benzhydryl acetate in place of the starting free alcohol allows lowering of the Lewis acid to catalytic amounts. A general mechanism for this scarcely studied C-C bond formation is presented. Due to the easier availability of alcohols with respect to halides the method may favorably compare with the more classical halide-based basic conditions.
Reactions of active methylene compounds with benzhydrol during solvolysis in formic acid
Gullickson, Glen C.,Lewis, David E.
, p. 385 - 388 (2003)
Formic acid reacts with benzhydrol to give benzhydryl formate, which reacts with active methylene compounds in refluxing formic acid to give either C-alkylation or Ritter reaction products. The product formed is determined by the equilibrium enol content of the active methylene compound. These reaction conditions avoid the use of halogenated reaction solvents, and the pure products are isolated without recourse to chromatography.
Monoallylation and benzylation of dicarbonyl compounds with alcohols catalysed by a cationic cobalt(iii) compound
Chandra Sau, Mohan,Mandal, Smita,Bhattacharjee, Manish
, p. 9235 - 9245 (2021/03/16)
Monoallylation and monoalkylation of diketones and β-keto esters with allylic and benzylic alcohols catalysed by [Cp*Co(CH3CN)3][SbF6]2(I) are reported. The method does not require any additive and affords regioselective products. The mechanistic investigations were done byin situ1H NMR spectroscopy as well as control experiments. It has been shown that reactions proceedviaη3-allyl complex formation or ally ether intermediate. The alkylation takes placeviaonly ether intermediate. The resulting allylated and alkylated products have been used for the synthesis of eleven new trisubstituted pyrazoles and one pyrazolone.
Air-stable μ2-hydroxyl bridged cationic binuclear complexes of zirconocene perfluorooctanesulfonates: their structures, characterization and application
Zhang, Xiaohong,Xu, Xinhua,Li, Ningbo,Liang, Zhiwu,Tang, Zilong
supporting information, p. 1926 - 1932 (2018/03/21)
Three air-stable zirconocene perfluoro-octanesulfonates were successfully synthesized by treatment of C8F17SO3Ag with (RCp)2ZrCl2 [R = H, n-Bu, t-Bu]. According to X-ray analysis, they have μ2-hydroxyl bridged cationic binuclear structures: (i) [CpZr(OH2)3]2(μ2-OH)2(OSO2C8F17)4·2THF·4H2O (1a·2THF·4H2O), (ii) [n-BuCpZr(OH2)3]2(μ2-OH)2(OSO2C8F17)4·6H2O (2a·6H2O), and (iii) [t-BuCpZr(OH2)3]2(μ2-OH)2(OSO2C8F17)4·2C3H6O·8H2O (3a·2C3H6O·8H2O). The ligands of water and organic molecules in the complexes originated from the moist air and solvent during their recrystallization. These complexes were characterized with different techniques, and found to show water tolerance, air/thermal stability as well as strong Lewis acidity. Moreover, the complexes showed highly catalytic activity in various reactions of C–C bond formation. With good recyclability, they should find wide applications in organic chemistry.
Base-free benzylation of 1,3-dicarbonyl compounds using sulfamic acid supported on silica by linker: a combined experimental and theoretical approach
Karimzadeh, Morteza,Saberi Asl, Hamed,Hashemi, Hajar,Saberi, Dariush,Niknam, Khodabakhsh
, p. 2237 - 2244 (2018/10/31)
Abstract: Sulfamic acid stabilized on the surface of silica by the n-propyl organic group linker which is named silica-bonded N-propylsulfamic acid was applied as an efficient heterogeneous catalyst with good recyclability and reusability for direct benzylation of 1,3-dicarbonyl compounds using secondary aromatic alcohols or styrenes as alkylating agents in high yields and short reaction times. All the reactions were carried out in nitromethane as solvent under an air atmosphere. The catalyst showed reusable feature by six times without a significant loss in its activity. Graphical abstract: [Figure not available: see fulltext.].
Protecting group-free use of alcohols as carbon electrophiles in atom efficient aluminium triflate-catalysed dehydrative nucleophilic displacement reactions
Cullen, Adam,Muller, Alfred J.,Williams, D. Bradley G.
, p. 42168 - 42171 (2017/09/11)
Benzylic and allylic alcohols are rendered electrophilic without chemical modification by the use of aluminium triflate as catalyst. The reaction succeeds with alcohol, thiol, carbon and nitrogen nucleophiles. When phenols are employed as nucleophiles, C-alkylation ensues. An advanced application of the method is demonstrated in the synthesis of 2H-chromenes and their N and S analogues.
Solvent-free alkylation of 1,3-dicarbonyl compounds with benzylic, propargylic and allylic alcohols catalyzed by La(NO3)3·6H2O
Subramanyam, Madala,Rao, Koya Prabhakara,Varala, Ravi,Rao, Mandava V. Basaveswara
, p. 1155 - 1160 (2016/03/01)
An efficient and solvent free method for benzylation, propargylation and allylation of 1,3-dicarbonyl compounds with alcohols has been developed by using La(NO3)3·6H2O as water tolerable catalyst. The reaction was shown to proceed smoothly for various 1,3-dicarbonyl compounds with benzylic, propargylic and allylic alcohols including 1° allylic alcohols, without any solvent, providing a clean access to the desired products in short reaction times with good to excellent yields and high selectivity.
Synthesis and structure of an air-stable bis(isopropylcyclopentadienyl) zirconium perfluorooctanesulfonate and its catalyzed benzylation of 1,3-dicarbonyl derivatives with alcohols
Zhang, Xiaohong,Qiu, Renhua,Zhou, Congcong,Yu, Jingxing,Li, Ningbo,Yin, Shuangfeng,Xu, Xinhua
, p. 1011 - 1017 (2015/01/30)
An air-stable uninuclear complex of bis(isopropylcyclopentadienyl) zirconium perfluorooctane sulfonate (1a·H2O·3THF) was successfully synthesized by the reaction of (i-PrCp)2ZrCl2 with C17SO3Ag. The c
Fe-catalyzed double cross-dehydrogenative coupling of 1,3-dicarbonyl compounds and arylmethanes
Yang, Kai,Song, Qiuling
supporting information, p. 548 - 551 (2015/03/05)
Fe-catalyzed tandem cross-dehydrogenative coupling of the methyl group in arylmethanes with 1,3-dicarbonyl compounds has been developed. The reaction affords one new C(sp3)-C(sp2) bond and one new C(sp3)-C(sp3)
Fe2(SO4)3·xH2O on silica: An efficient and low-cost catalyst for the direct nucleophilic substitution of alcohols in solvent-free conditions
Li, Lingjun,Zhu, Anlian,Zhang, Yuqin,Fan, Xincui,Zhang, Guisheng
, p. 4286 - 4291 (2014/01/17)
Fe2(SO4)3·xH2O on silica has been found to be a novel efficient catalyst for the direct nucleophilic substitution of alcohols in solvent-free conditions. In this reaction system, the alcohols can react with various nucleophilic reagents for the convenient construction of C-C bonds and C-N bonds with the benefits of high conversion, no requirement to use excessive amounts of the nucleophile, only a catalytic amount of iron catalyst required, solvent-free and benign reaction conditions, and the feasible reusability of the catalyst.
