- Amides as surrogates of aldehydes for C-C bond formation: amide-based direct Knoevenagel-type condensation reaction and related reactions
-
Aldehydes are perhaps the most versatile compounds that enable many C-C bond forming reactions, which are not amenable for other subclasses of carbonyl compounds. We report the first use of amides as surrogates of aldehydes for C-C bond formation, namely,
- Ou, Wei,Huang, Pei-Qiang
-
-
- Heterogeneous ring-opening reactions and Knoevenagel condensation reactions with cobalt complexes: Effect of CoII versus CoIII states on catalysis
-
This work illustrates comparative catalytic performance of two sets of cobalt complexes within a common macrocyclic ligand environment: CoII complexes 1 and 2 versus CoIII complexes 3 and 4. All four cobalt complexes functioned as the heterogeneous catalysts for the ring-opening reactions of assorted epoxides as well as Knoevenagel condensation reactions of assorted aldehydes. Cobalt(II) complexes were noted to be the superior catalysts over cobalt(III) complexes for both types of organic transformations. The observed difference in the catalytic performance of two sets of cobalt complexes has been related to the kinetic differences between CoII versus CoIII ions. All four cobalt complexes display high catalytic efficiency and excellent reusability without any apparent loss in the catalytic performance.
- Kumar, Sushil,Gupta, Rajeev
-
p. 843 - 852
(2020/06/26)
-
- Development of the First Two-Pore Domain Potassium Channel TWIK-Related K+ Channel 1-Selective Agonist Possessing in Vivo Antinociceptive Activity
-
The TWIK-related K+ channel, TREK-1, has recently emerged as an attractive therapeutic target for the development of a novel class of analgesic drugs, suggesting that activation of TREK-1 could result in pain inhibition. Here, we report the synthesis of a series of substituted acrylic acids (1-54) based on our previous work with caffeate esters. The analogues were evaluated for their ability to modulate TREK-1 channel by electrophysiology and for their in vivo antinociceptive activity (acetic acid-induced writhing and hot plate assays), leading to the identification of a series of novel molecules able to activate TREK-1 and displaying potent antinociceptive activity in vivo. Furyl analogue 36 is the most promising of the series.
- Vivier, Delphine,Soussia, Ismail Ben,Rodrigues, Nuno,Lolignier, Stéphane,Devilliers, Ma?ly,Chatelain, Franck C.,Prival, Laetitia,Chapuy, Eric,Bourdier, Geoffrey,Bennis, Khalil,Lesage, Florian,Eschalier, Alain,Busserolles, Jér?me,Ducki, Sylvie
-
supporting information
p. 1076 - 1088
(2017/02/19)
-
- MOF derived mesoporous K-ZrO2 with enhanced basic catalytic performance for Knoevenagel condensations
-
Mesoporous K-ZrO2 are designed and synthesized through a direct heat-treatment process of a KNO3 loaded UiO-66 metal organic framework. Very interestingly, the carbon intermediates formed during the heat-treatment process can act bot
- Wang, Peng,Feng, Jian,Zhao, Yupei,Gu, Sai,Liu, Jian
-
p. 55920 - 55926
(2017/12/26)
-
- A carboxylate-rich metalloligand and its heterometallic coordination polymers: Syntheses, structures, topologies, and heterogeneous catalysis
-
This work reports three heterometallic coordination polymers (HCPs), namely, [{(1′)2Zn8Na2(H2O)21}·20H2O]n (2), [{(1′)(1')Cd8(H2O)21}·32H2/
- Srivastava, Sumit,Kumar, Vijay,Gupta, Rajeev
-
p. 2874 - 2886
(2016/06/01)
-
- Nitrided ITQ-2 as an efficient Knoevenagel condensation catalyst
-
The nitrogen-substituted delaminated ITQ-2 zeolite was found to be a highly active and recyclable catalyst for the Knoevenagel condensation of bulky aromatic aldehydes with ethyl cyanoacetate which cannot take place over the base sites placed within the micropores of conventional zeolites due to spatial limitations.
- Min, Hyung-Ki,Cha, Seung Hyeok,Hong, Suk Bong
-
p. 1115 - 1117
(2013/02/25)
-
- Critical assessment of the efficiency of chitosan biohydrogel beads as recyclable and heterogeneous organocatalyst for C-C bond formation
-
The effectiveness of neutral pH chitosan hydrogel beads (CSHB) as a green organocatalyst for a variety of C-C bond forming reactions (i.e. aldol reaction, Knoevenagel condensation, nitroaldol (Henry) reaction, Michael addition) has been comprehensively evaluated. Reaction rates, conversions and selectivities were studied as a function of a series of input variables including size, pH and reactive surface area of the beads, catalyst loading, temperature, molecular weight of the biopolymer, concentration, solvent system and molar ratio of reactants. Moreover, the catalytic biohydrogel beads were characterized by a variety of techniques including, among others, SEM, FT-IR, TGA and DSC.
- Kuehbeck, Dennis,Saidulu,Reddy, K. Rajender,Diaz, David Diaz
-
supporting information; experimental part
p. 378 - 392
(2012/04/10)
-
- Synthesis of highly stable CoFe2O4 nanoparticles and their use as magnetically separable catalyst for Knoevenagel reaction in aqueous medium
-
Synthesis of spinel cobalt ferrite magnetic nanoparticles (MNPs) with average sizes in the range 40-50 nm has been achieved using a combined sonochemical and co-precipitation technique in aqueous medium without any surfactant or organic capping agent. The nanoparticules form stable dispersions in aqueous or alcoholic medium. The uncapped nanoparticles were utilized directly as a reusable catalyst for Knoevenagel reaction in aqueous ethanol (1:3). Compartmentation and recovery of the catalyst from reaction medium was done with the aid of an external magnet. High yield of corresponding Knoevenagel products were obtained within a very short time in presence of just 5 mol% of the catalyst at 50 °C.
- Senapati, Kula Kamal,Borgohain, Chandan,Phukan, Prodeep
-
experimental part
p. 24 - 31
(2011/05/17)
-
- Efficient asymmetric synthesis of 4H-chromene derivatives through a tandem michael addition-cyclization reaction catalyzed by a salen-cobalt(II) complex
-
The asymmetric synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromene derivatives was achieved through a tandem Michael addition-cyclization reaction of easily available cyclohexane-1,3-dione and ethyl 2-cyano-3-phenylacrylates. Moderate to good yields (up to 81%) and high enantioselectivities (up to 89%ee) were obtained with a chiral salen-cobalt(II) complex. This process was air tolerant and easily performed, which provides an efficient method for the synthesis of chiral 4H-chromene derivatives. The asymmetric synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromene derivatives was achieved through a tandem Michael addition-cyclization reaction of easily available cyclohexane-1,3-dione and ethyl 2-cyano-3-phenylacrylates catalyzed by a chiral salen-cobalt(II) complex with moderate to good yields (up to 81%) and high enantioselectivities (up to 89%ee).
- Dong, Zhenhua,Liu, Xiaohua,Feng, Juhua,Wang, Min,Lin, Lili,Feng, Xiaoming
-
supporting information; experimental part
p. 137 - 142
(2011/03/18)
-
- Size control of catalytic reaction space by intercalation of alkylcarboxylate anions into Ni-Zn mixed basic salt interlayer: Application for knoevenagel reaction in water
-
The interlayer space of layered Ni-Zn mixed basic salt (NiZn) can be controlled precisely by the intercalation of various carboxylate anions with long alkyl chains via simple anion exchange. Expansion of interlayer space in the anion-exchanged NiZn depend
- Hara, Takayoshi,Kurihara, Jun,Ichikuni, Nobuyuki,Shimazu, Shogo
-
supporting information
p. 304 - 305
(2012/11/07)
-
- One-pot formation of functionalised 2-piperidinones from arylidenecyanoacetates and methanolic ammonia via tandem reactions
-
Aryl aldehydes react with ethyl cyanoacetate in methanolic ammonium acetate to expeditiously furnish, besides high yields of arylidenecyanoacetates, 4,6-diaryl-3,5-dicyano-5-ethoxycarbonyl-2-piperidinonesinlow yields. But preformed arylidenecyanoacetates
- Chakrabarty, Manas,Karmakar, Sulakshana,Arima, Shiho,Harigaya, Yoshihiro
-
experimental part
p. 795 - 804
(2009/09/25)
-
- Chitosan hydrogel: A green and recyclable biopolymer catalyst for aldol and Knoevenagel reactions
-
Chitosan hydrogel is efficiently utilized as an organocatalyst for aldol and Knoevenagel reactions, providing the products in high yields with a high chemoselectivity under biphasic conditions. The catalyst was recovered by simple filtration and reused several times without significant loss of activity. the Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2006.
- Reddy, K. Rajender,Rajgopal,Maheswari, C. Uma,Lakshmi Kantam
-
p. 1549 - 1552
(2007/10/03)
-
- CATALYSIS OF THE KNOEVENAGEL CONDENSATION.
-
Xonotlite alone or made more basic by doping of potassium t-butoxide catalyses the title reaction between aromatic aldehydes and malononitrile or alkyl cyanoacetates.At ambient temperatures, this procedure specifically gives high yields of E olefinic Knoe
- Chalais, Stephane,Laszlo, Pierre,Mathy, Arthur
-
p. 4453 - 4454
(2007/10/02)
-