26728-49-4Relevant academic research and scientific papers
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.
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.].
Direct Zinc(II)-Catalyzed Enantioconvergent Additions of Terminal Alkynes to α-Keto Esters
Zavesky, Blane P.,Johnson, Jeffrey S.
supporting information, p. 8805 - 8808 (2017/07/17)
The addition of terminal alkynes to racemic β-stereogenic α-keto esters was achieved in high levels of stereoselectivity, affording versatile tertiary propargylic alcohols containing two stereocenters. This environmentally benign enantioconvergent reaction proceeds with perfect atom economy, requires no solvent, and is catalyzed by a non-toxic zinc salt. The alkyne moiety can be leveraged in downstream transformations including hydrogenation to the corresponding saturated tertiary alcohol, which represents the product of a formal enantioconvergent aliphatic nucleophile addition.
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.
Fe(HSO4)3 : An efficient, heterogeneous and reusable catalyst for C-alkylation of β-dicarbonyl compounds
Khafajeh, Samaneh,Akhlaghinia, Batool,Rezazadeh, Soodabeh,Eshghi, Hossein
, p. 1903 - 1912 (2015/02/05)
Fe(HSO4)3(FHS) was used as an efficient catalyst for the heterogeneous addition of a series of benzylic and allylic alcohols to various β-dicarbonyl compounds, which afforded moderate to excellent yields of C-alkylated products in 1,2-dichloroethane. In comparison with the previous methods, the present research surprisingly exhibited higher reaction yields without formation of any by-products which could be formed by self-condensation of alcohols. Moreover, the catalyst can be readily recovered and reused up to five times with almost maintained reactivity and yields.
FeCl3-catalyzed addition of nitrogen and 1,3-dicarbonyl nucleophiles to olefins
Zotto, Christophe Dal,Michaux, Julien,Zarate-Ruiz, Araceli,Gayon, Eric,Virieux, David,Campagne, Jean-Marc,Terrasson, Vincent,Pieters, Grégory,Gaucher, Anne,Prim, Damien
experimental part, p. 296 - 304 (2011/02/17)
A direct intermolecular addition of nitrogen and 1,3-dicarbonyl nucleophiles to stabilized double bonds (styrenes, 1,3-dienes, enol-ethers, sugars.) in the presence of green and inexpensive FeCl3 catalyst is described.
Amberlyst-15 in ionic liquid: an efficient and recyclable reagent for the benzylation and hydroalkylation of β-dicarbonyl compounds
Qureshi, Ziyauddin S.,Deshmukh, Krishna M.,Tambade, Pawan J.,Bhanage, Bhalchandra M.
scheme or table, p. 724 - 729 (2010/04/05)
Benzylation and hydroalkylation of 1,3-dicarbonyl compounds using Amberlyst-15 immobilized in ionic liquid [Bmim][PF6] as an efficient reusable reagent was studied. The reagent was compared with other solid acid reagents along with role of the ionic liquid. The effect of various reaction parameters like type of reagent, solvent, substrate molar ratio, reaction time, and temperature were studied. Present protocol is advantageous due to the ease in handling of reagent, simple work-up procedure, economical and environmentally benign process. The products were obtained in good to excellent yield and applicable to wide variety of substrates.
Benzylation of β-dicarbonyl compounds and 4-hydroxycoumarin using TMSOTf catalyst: A simple, mild, and efficient method
Theerthagiri, Palani,Lalitha, Appaswami
supporting information; experimental part, p. 5454 - 5458 (2010/11/02)
The direct benzylation of 1,3-dicarbonyl compounds and 4-hydroxycoumarin with a wide variety of benzylic alcohols was achieved using trimethylsilyl trifluoromethanesulfonate as an efficient catalyst. The reaction proceeded under very mild conditions at ro
Br?nsted acid ionic liquid-catalyzed direct benzylation, allylation and propargylation of 1,3-dicarbonyl compounds with alcohols as well as one-pot synthesis of 4H-chromenes
Funabiki, Kazumasa,Komeda, Takuya,Kubota, Yasuhiro,Matsui, Masaki
experimental part, p. 7457 - 7463 (2009/12/06)
Recyclable ionic Br?nsted acid was prepared in nearly quantitative yield by reacting 1-butylimidazole with an equimolar amount of 1,3-propanesultone, followed by treatment with an equimolar amount of trifluoromethanesulfonic acid. The ionic Br?nsted acid-catalyzed direct benzylation, allylation and propargylation of 1,3-dicarbonyl compounds with various alcohols in ionic liquid [N-ethyl-N-methyl imidazolium trifluoromethanesulfonate (EMIOTf)], at 100 °C for 3 h proceeded smoothly to give the corresponding products in good to excellent yields without the use of any hazardous or volatile solvents and without any by-product such as salts. Furthermore, tandem benzylation-cyclization-dehydration of 1,3-dicarbonyl compounds to give functionalized 4H-chromenes was also achieved in this catalytic reaction.
An efficient iodine-catalyzed benzylation reaction of 1,3-dicarbonyl compounds
Li, Zhongxian,Duan, Zheng,Wang, Huaiqiu,Tian, Rongqiang,Zhu, Qianrui,Wu, Yangjie
scheme or table, p. 2535 - 2539 (2009/05/07)
Under mild conditions, iodine promotes the direct alkylation of 1,3-dicarbonyl compounds with benzylic alcohols or benzylic acetates. Georg Thieme Verlag Stuttgart.
