- Synthesis and crystal structure of 5-(4-methoxybenzylidene)-2,2-dimethyl-1, 3-dioxane-4,6-dione
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A new Meldrum's acid compound 5-(4-methoxybenzylidene)-2,2-dimethyl-1,3- dioxane-4,6-dione was prepared by 2,2-dimethyl-1,3-dioxane- 4,6-dione with 4-methoxybenzaldehyde in ethanol and its crystal structure was determined by X-ray crystallographic techniq
- Zeng, Wulan
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- Meldrum's acid catalyzed reaction of tetracyanoethylene and aldehydes in water: A novel approach to arylidenemalononitrile
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Meldrum's acid catalyzed the reaction of tetracyanoethylene with aromatic, heteroaromatic, and conjugated aldehydes led to arylidenemalononitrile in water in good yields at 80° C. The work-up of reactions is very simple and the crude products are sufficiently pure to be used without further purification. The procedure provides an alternative method for the synthesis of arylidenemalononitrile.
- Shaabani, Ahmad,Rezayan, Ali Hossein,Heidary, Marjan,Sarvary, Afshin
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- Synthesis, crystal structure and molecular modeling (AM1) of two 5-arylidene derivatives of Meldrum's acid
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The synthesis and structural characterization of two 5-Arylidene derivatives of Meldrum's acid (2,2-dimethyl-1,3-dioxane-4,6-dione) are described: 5-(4-Nitrobenciliden)-2,2-dimethyl-1,3-dioxane-4,6-dione (3a), and 5-(4-Methoxybenciliden)-2,2-dimethyl-1,3-
- De Armas, Hector Novoa,Blaton, Norbert M.,Peeters, Oswald M.,De Ranter, Camiel J.,Suarez, Margarita,Ochoa, Estael,Verdecia, Yamila,Salfran, Esperanza
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- A novel light induced Knoevenagel condensation of Meldrum's acid with aromatic aldehydes in aqueous ethanol
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A highly efficient environment-friendly photochemical methodology has been developed for the condensation of Meldrum's acid with aromatic aldehydes in water-ethanol solution sans any catalyst, support or promoter.
- Ghosh, Somnath,Das, Jhantu,Chattopadhyay, Subhagata
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Read Online
- Clean synthesis in water. Part 2: Uncatalysed condensation reaction of Meldrum's acid and aldehydes
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The environment-friendly condensation of Meldrum's acid and aromatic, heteroaromatic and hindered aliphatic aldehydes is performed carrying out the reaction in water at 75°C for 2 h, avoiding the addition of any catalyst.
- Bigi, Franca,Carloni, Silvia,Ferrari, Leonetto,Maggi, Raimondo,Mazzacani, Alessandro,Sartori, Giovanni
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Read Online
- Bentonite catalyzed an efficient and green synthesis of arylidene meldrum's acid derivatives in aqueous media
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In the present paper, a simple, highly efficient, and environmentally friendly protocol was proposed for the Knoevenagel condensation reaction of aromatic aldehydes using Meldrum’s acid (2,2-dimethyl-4,6-dioxo-1,3-dioxane) with bentonite as an available n
- Yahyazadehfar, Mahdieh,Ahmadi, Sayed Ali,Sheikhhosseini, Enayatollah,Ghazanfari, Dadkhoda
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p. 513 - 519
(2021/07/25)
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- Enantioselective Ammonium Ylide Mediated One-Pot Synthesis of Highly Substituted γ-Butyrolactones
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An ammonium ylide mediated access towards trans-β,γ-disubstituted, all-trans-α,β,γ-trisubstituted, and α,α,β,γ-tetrasubstituted γ-butyrolactones bearing a broad variety of functionalities was developed. Starting from widely accessible benzylidene Meldrum's acid derivatives and α-bromo carbonyl compounds, γ-butyrolactones were obtained in yields between 32–99% with up to excellent diastereoselectivities (>95:5) via a DABCO-mediated [2+1] annulation. Utilization of enantiomerically pure cinchona alkaloid derivatives enables the first asymmetric ammonium ylide mediated method to provide (3R,?4R)-β,γ-disubstituted and (2R,?3R,?4R)-α,β,γ-trisubstituted γ-butyrolactones in moderate to good yields with up to very good enantiomeric ratios (97:3). The scalability of the transformation was proven while determining the absolute configuration. (Figure presented.).
- Drennhaus, Till,?hler, Laura,Djalali, Saveh,H?fmann, Svenja,Müller, Clemens,Pietruszka, J?rg,Worgull, Dennis
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supporting information
p. 2385 - 2396
(2020/04/30)
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- Boron/zinc exchange for the conjugate arylation of unsaturated Meldrum's acid derivatives
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An approach for the conjugate arylation reaction of unsaturated Meldrum's acid derivatives is reported. The reaction takes place through a Boron-Zinc exchange reaction between arylboronic acids and diethylzinc and the subsequent transfer of thus generated reactive aryl groups to the β-position of the double bond of the Meldrum's derivatives. The compounds obtained are valuable synthetic intermediates and can give rise to bioactive molecules such as β,β-disubstituted carboxylic acids and amides.
- Jardim, Micaela,Baldassari, Lucas L.,Contreira, Maria Eduarda,Moro, Angélica V.,Lüdtke, Diogo S.
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supporting information
(2020/01/31)
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- An alternative, practical, and ecological protocol for synthesis of arylidene analogues of Meldrum’s acid as useful intermediates
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This paper presents an ecological protocol for Knoevenagel condensation using a catalytic amount of 4,4′-trimethylenedipiperidine as a versatile, efficient, safe, commercially available, inexpensive, and recyclable organocatalyst by a ball-milling process
- Khaligh, Nader Ghaffari,Mihankhah, Taraneh,Johan, Mohd Rafie
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- Microwave-associate synthesis of Co3O4 nanoparticles as an effcient nanocatalyst for the synthesis of arylidene barbituric and Meldrum's acid derivatives in green media
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In this study, Co3O4 nanocatalysts were constructed in environmentally appropriate conditions using controlled, effective, and facile microwave method. The final nanostructures were characterized by SEM, XRD, and TEM analyses. The products had a small size distribution, homogeneous morphology, and crystallographic structures associated with the formation of Co3O4 nanostructures. Moreover, EDS mapping analysis confirmed the existence of Co and O elements in the final structure, and the magnetic properties of the samples were investigated by VSM. The application of this nanostructure in a catalytic process was further examined, and the results suggested that it could be used as a novel candidate for the synthesis of arylidene barbituric and Meldrum,s acid through Knoevenagel condensation of aldehydes by barbituric and Meldrum,s acid in aqueous media. The high yield of these nanocatalysts would be justified by the nature of the nanostructure as well as the experimental procedure developed in this study, which affected the physicochemical features of the products.
- Yahyazadehfar, Mahdieh,Sheikhhosseini, Enayatollah,Ahmadi, Sayed Ali,Ghazanfari, Dadkhoda
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- A transition metal free expedient approach for the C[dbnd]C bond cleavage of arylidene Meldrum's acid and malononitrile derivatives
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A transition metal free expedient approach for the C[dbnd]C bond cleavage of electron deficient alkenes such as arylidene Meldrum's acid and malononitrile derivatives are discussed. The C[dbnd]C bond of these compound were cleaved to benzoic acid in good yield at high temperature. Most importantly, with oxone in CH3CN/H2O at 45 °C or m-CPBA in DCM or NaClO2 in THF/H2O or PIDA in THF at room temperature furnished benzaldehyde derivatives selectively in excellent yields.
- Suresh, Muthiah,Kumari, Anusueya,Singh, Raj Bahadur
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- Dynamic Covalent Metathesis in the C=C/C=N Exchange between Knoevenagel Compounds and Imines
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Fast and reversible dynamic covalent C=C/C=N exchange takes place without catalyst in nonpolar solvents between barbiturate-derived Knoevenagel (Kn) compounds and imines. A detailed study of the reaction indicates that it proceeds by an associative organo-metathesis mechanism involving the formation of a four-membered ring azetidine intermediate by addition of the imine C=N group to the C=C bond of the Kn compound. This intermediate could be generated cleanly and stabilized at low temperature by condensation of the o,p-dinitrophenyl Kn derivative with the cyclic imine 1-azacyclohexene. It was characterized by extensive NMR and mass spectrometric studies. The process described represents a genuine dynamic covalent organo-metathesis through a four-membered ring adduct as intermediate. It paves the way for the exploration of a wide set of dynamic systems involving (strongly) polarized C=C bonds and various imines, extending also into covalent dynamic polymers and polymolecular assemblies.
- Gu, Ruirui,Flidrova, Karolina,Lehn, Jean-Marie
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supporting information
p. 5560 - 5568
(2018/05/01)
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- An Adverse Effect of Higher Catalyst Loading and Longer Reaction Time on Enantioselectivity in an Organocatalytic Multicomponent Reaction
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An enantioselective organocatalytic multicomponent reaction of aldehydes, ketones, and Meldrum's acid has been developed. A cinchona-based primary amine (1 mol %) catalyses the multicomponent reaction via the formation of the Knoevenagel product and a chiral enamine to form enantiopure δ-keto Meldrum's acids in a tandem catalytic pathway. An adverse effect of higher catalyst loading and longer reaction time on enantioselectivity was studied. This mild protocol provides an easy access to enantiopure carboxylic acids, esters and amides and the method is scalable on a gram quantity. DFT calculations were carried out on the proposed reaction mechanism and they were in close agreement with the experimental results.
- Khopade, Tushar M.,Mete, Trimbak B.,Arora, Jyotsna S.,Bhat, Ramakrishna G.
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supporting information
p. 6036 - 6040
(2018/04/27)
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- Diversity-oriented Multicomponent Heterocyclizations Involving Derivatives of 3(5)-Aminoisoxazole, Aldehydes and Meldrum's or N,N′-Dimethylbarbituric Acid
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5-Amino-3-methylisoxazole and 3-amino-5-methylisoxazole were studied in details in the multicomponent heterocyclizations with aromatic aldehydes and Meldrum's or N,N′-dimethylbarbituric acid with help of classical and non-classical (microwave and ultrasonic irradiation) activation methods.
- Morozova, Alisa D.,Muravyova, Elena A.,Shishkina, Svitlana V.,Vashchenko, Elena V.,Sen'ko, Yulia V.,Chebanov, Valentin A.
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p. 932 - 943
(2017/03/27)
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- Co(NO3)2·6H2O as a powerful and reusable catalyst for the synthesis of phenylbenzo[g]chromenes
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An efficient and easy protocol for the one-pot three-component synthesis of phenylbenzo[g]chromenes was developed. The synthesis was achieved by the reaction of aromatic aldehydes, Meldrum’s acid, and 2-hydroxynaphthalene-1,4-dione in the presence of cata
- Kangani, Mehrnoush,Hazeri, Nourallah,Maghsoodlou, Malek-Taher
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p. 2659 - 2664
(2017/11/06)
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- A PI3K/Akt Raf/MEK/ERK and as the target of the double-channel inhibitors
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The invention discloses a dual-channel inhibitor using Raf/MEK/ERK and PI3K/Akt as targets. The chemical name of the composition is 1-(2-amido) ethyl-3-(3-(4-methoxyl) phenyl) allyl indole-2-ketone hydrochloride, and the structural formula (I) of the composition is as shown in the specification. The invention also discloses a preparation method of the composition and an application of the composition for preparing an anti-tumor drug. The dual-channel inhibitor disclosed by the invention has the advantages of improving titer and reducing the occurrence probability of drug resistance as well as reducing toxicity and improving the compliance of patients. Thus, the design and development of the dual-channel inhibitor provide a new chemical tool for cancer research groups, and the dual-channel inhibitor is possible to be developed as a new anti-cancer agent.
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Paragraph 0031; 0044; 0045
(2016/11/09)
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- Synthesis of bis-spiro cyclopropanes based on Meldrum's acid by milling
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Reaction of 2,2-dimethyl-1,3-dioxane-4,6-dione (Meldrum's acid) with various solid aldehydes in the presence of cyanogen bromide and solid sodium ethoxide (EtONa) leads to the selective and efficient formation of bis-spiro cyclopropanes based on Meldrum's acid at the range of 0 °C to room temperature. The products were obtained in good to excellent yields. Structure elucidation is carried out by 1H NMR, 13C NMR, FT-IR spectroscopy, mass analyses and X-ray crystallography techniques. A possible mechanism for the formation of products is also discussed under solvent-free condition.
- Kashani, Elmira,Noroozi Pesyan, Nader,Tun?, Tuncay,Sahin, Ertan
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p. 249 - 256
(2015/03/31)
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- 2,3-BENZODIAZEPINES
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What is described are BET protein-inhibitory, in particular BRD4-inhibitory 2,3-benzodiazepines of the general formula (I) in which R1a, R1b, R1c, R2, R3, R4, R5, A and X have the meanings given in the description, intermediates for preparing the compounds according to the invention, pharmaceutical compositions comprising the compounds according to the invention and their prophylactic and therapeutic use for hyperproliferative disorders, in particular for tumour disorders. Also described is the use of BET protein inhibitors for benign hyperplasias, atherosclerotic disorders, sepsis, autoimmune disorders, vascular disorders, viral infections, for neurodegenerative disorders, for inflammatory disorders, for atherosclerotic disorders and for the control of male fertility.
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Paragraph 1638
(2015/07/27)
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- 2, 3-benzodiazepins
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What is described are BET protein-inhibitory, in particular BRD4-inhibitory 2,3-benzodiazepines of the general formula (I) in which R1a, R1b, R1c, R2, R3, R4, R5, A and X have the meanings given in the description, intermediates for preparing the compounds according to the invention, pharmaceutical compositions comprising the compounds according to the invention and their prophylactic and therapeutic use for hyperproliferative disorders, in particular for tumour disorders. Also described is the use of BET protein inhibitors for benign hyperplasias, atherosclerotic disorders, sepsis, autoimmune disorders, vascular disorders, viral infections, for neurodegenerative disorders, for inflammatory disorders, for atherosclerotic disorders and for the control of male fertility.
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Paragraph 0485-0486
(2016/10/08)
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- Di- and triarylmethylium ions as probes for the ambident reactivities of carbanions derived from 5-benzylated Meldrum's acid
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The kinetics of the reactions of carbocations with carbanions 1 derived from 5-benzyl-substituted Meldrum's acids 1-H (Meldrum's acid=2,2-dimethyl-1,3- dioxane-4,6-dione) were investigated by UV/Vis spectroscopic methods. Benzhydryl cations Ar2CH+ added exclusively to C-5 of the Meldrum's acid moiety. As the second-order rate constants (kC) of these reactions in DMSO followed the linear free-energy relationship lg k=s N(N+E), the nucleophile-specific reactivity parameters N and s N for the carbanions 1 could be determined. In contrast, trityl cations Ar3C+ reacted differently. While tritylium ions of low electrophilicity (E-2) reacted with 1 through rate-determining β-hydride abstraction, more Lewis acidic tritylium ions initially reacted at the carbonyl oxygen of 1 to form trityl enolates, which subsequently reionized and eventually yielded triarylmethanes and 5-benzylidene Meldrum's acids by hydride transfer.
- Chen, Xi,Tan, Yue,Berionni, Guillaume,Ofial, Armin R.,Mayr, Herbert
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supporting information
p. 11069 - 11077
(2014/10/15)
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- Synthesis of new guanidium-meldrum acid zwitterionic salts and dynamic NMR study of rotational energy barrier around C-NH bond of guanidine moiety
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Synthesis of the Guanidium-Meldrum acid zwitterionic salts was developed through a three component reaction of 2, 2-dimethyl-1, 3-dioxane-4, 6-dione (Meldrum acid), aromatic aldehydes and N, N, N', N'- Tetramethyl-guanidine in benzen at room temperature.
- Aminkhani, Ali
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p. 1791 - 1797
(2015/04/27)
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- Synthesis of 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones and coumarin-3-carboxylic acids via reaction of nitrones and Meldrum's acid
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A variety of nitrones have been synthesized and reacted with Meldrum's acid without the aid of any catalysts. Selectively, 5- arylidene-2,2-dimethyl-1,3- dioxane-4,6-diones have been obtained with excellent yields under environmentally benign reaction conditions. Whereas, nitrone of salisylaldehydes with Meldrum's acid afford cyclized products i.e. coumarin-3- carboxylic acids.
- Kumar, Dhruva,Suresh,Sandhu, Jagir S.
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p. 1157 - 1160
(2013/09/24)
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- Synthesis of a new urea derivative: A dual-functional organocatalyst for Knoevenagel condensation in water
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A phenylalanine-urea compound-catalyzed Knoevenagel condensation in water is reported. Various aldehydes and active methylene compounds undergo condensation at room temperature to give the desired products in high yields. The mechanism of the condensation of aldehydes with Meldrum's acid catalyzed by the novel urea derivative is also disclosed.
- Le, Wen-Jun,Lu, Hong-Fei,Zhou, Jun-Tao,Cheng, He-Long,Gao, Yu-Hua
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p. 5370 - 5373
(2013/09/12)
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- A practical and convenient protocol for the synthesis of (E)-α,β-unsaturated acids
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α,β-Unsaturated acids are very useful and versatile reagents in organic synthesis. A novel, practical, and convenient catalytic protocol comprising FeCl3·6H2O (0.5 mol %) and H 2O (1 equiv) in CH3NO2 is described for the rapid synthesis of α,β-unsaturated acids with high E-stereoselectivity under both microwave and conventional heating conditions with high TON and TOF values. This powerful approach efficiently demonstrated the utility of biomass derived aldehydes to build chemical agents used as fuel additives. The method proved to be scalable to gram scale synthesis.
- Mohite, Amar R.,Bhat, Ramakrishna G.
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supporting information
p. 4564 - 4567
(2013/09/24)
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- Determination of thermodynamic affinities of various polar olefins as hydride, hydrogen atom, and electron acceptors in acetonitrile
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A series of 69 polar olefins with various typical structures (X) were synthesized and the thermodynamic affinities (defined in terms of the molar enthalpy changes or the standard redox potentials in this work) of the polar olefins obtaining hydride anions, hydrogen atoms, and electrons, the thermodynamic affinities of the radical anions of the polar olefins (X ?-) obtaining protons and hydrogen atoms, and the thermodynamic affinities of the hydrogen adducts of the polar olefins (XH?) obtaining electrons in acetonitrile were determined using titration calorimetry and electrochemical methods. The pure Ci - 'C π-bond heterolytic and homolytic dissociation energies of the polar olefins (X) in acetonitrile and the pure Ci - 'C π-bond homolytic dissociation energies of the radical anions of the polar olefins (X?-) in acetonitrile were estimated. The remote substituent effects on the six thermodynamic affinities of the polar olefins and their related reaction intermediates were examined using the Hammett linear free-energy relationships; the results show that the Hammett linear free-energy relationships all hold in the six chemical and electrochemical processes. The information disclosed in this work could not only supply a gap of the chemical thermodynamics of olefins as one class of very important organic unsaturated compounds but also strongly promote the fast development of the chemistry and applications of olefins.
- Cao, Ying,Zhang, Song-Chen,Zhang, Min,Shen, Guang-Bin,Zhu, Xiao-Qing
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p. 7154 - 7168
(2013/08/23)
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- 3-(2-AMINO-ETHYL)-ALKYLIDENE)-THIAZOLIDINE-2,4-DIONE AND 1-(2-AMINO-ETHYL)-ALKYLIDENE-1,3-DIHYDRO-INDOL-2-ONE DERIVATIVES AS SELECTIVE SPHINGOSINE KINASE 2 INHIBITORS
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3-(2-amino-ethyl)-5-[3-(4-substituted-phenyl)-alkylidene)-thiazolidine-2,4-dione and l-(2-amino-ethyl)-3-alkylidene-l,3-dihydro-indol-2-one and derivatives thereof are provided for use as selective SphK2 inhibitors and for use in the treatment of human diseases, such as cancer.
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Page/Page column 27
(2013/08/28)
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- Discovery and preliminary SAR of 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6- diones as platelet aggregation inhibitors
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We herein document the discovery of 5-arylidene-2,2-dimethyl-1,3-dioxane-4, 6-diones as a novel family of platelet aggregation inhibitors. The preliminary optimization study enabled us to establish the most salient features of the structure-activity relat
- El Maatougui, Abdelaziz,Azuaje, Jhonny,Coelho, Alberto,Yaziji, Vicente,Carbajales, Carlos,Sotelo, Eddy,Lopez, Carmen,Cano, Ernesto,Yanez, Matilde
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p. 551 - 554,4
(2020/08/31)
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- 3,5-Disubstituted-thiazolidine-2,4-dione analogs as anticancer agents: Design, synthesis and biological characterization
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A series of 2,5-disubstituted-thiazolidine-2,4-dione analogs based on the newly identified lead 1, a potential anticancer agent via the inhibition of the Raf/MEK/extracellular signal regulated kinase (ERK) and phosphatidylinositol 3-kinase (PI3K)/Akt signaling cascades, were synthesized and biologically characterized. A new lead structure, 15, was identified to have improved anti-proliferative activities in U937 cells, to induce apoptosis in U937, M12 and DU145 cancer cells, and to arrest U937 cells at the S-phase. Furthermore, Western blot analysis demonstrated a correlation of the anti-proliferative activity and blockade of the Raf/MEK/ERK and PI3K/Akt signaling pathways. Collectively, these results strongly encourage further optimization of 15 as a new lead with multi-target properties to develop more potent compounds as anticancer agents.
- Liu, Kai,Rao, Wei,Parikh, Hardik,Li, Qianbin,Guo, Tai L.,Grant, Steven,Kellogg, Glen E.,Zhang, Shijun
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experimental part
p. 125 - 137
(2012/03/08)
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- Carbon-based leaving group in substitution reactions: Functionalization of sp3-hybridized quaternary and tertiary benzylic carbon centers
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Lewis acid promoted substitution reactions employing Meldrum's acid and 5-methyl Meldrum's acid as carbon-based leaving groups are described which transform unstrained quaternary and tertiary benzylic Csp 3-Csp3 bonds into Csp3-X bonds (X = C, H, N). Importantly, this reaction has a broad scope in terms of both suitable substrates and nucleophiles with good to excellent yields obtained (typically >90%).
- Mahoney, Stuart J.,Lou, Tiantong,Bondarenko, Ganna,Fillion, Eric
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supporting information; scheme or table
p. 3474 - 3477
(2012/09/05)
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- A domino protocol for the efficient synthesis of structurally diverse benzothiazolylquinoline-2,5-diones and their spiro analogues
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Structurally diverse benzothiazolylquinoline-2,5-diones and their spiro analogues have been synthesized by an environmentally benign efficient and convenient synthetic method involving sulfamic acid catalyzed one-pot four-component reaction of Meldrum aci
- Gupta, Sunil Kumar,Kumar, Mahendra,Arya, Anand Kumar
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p. 6035 - 6038,4
(2020/08/20)
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- Nickel nanoparticles catalyzed chemoselective Knoevenagel condensation of Meldrum's acid and tandem enol lactonizations via cascade cyclization sequence
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A novel protocol has been reported wherein, polyethylene glycol (PEG) stabilized nickel nanoparticles have been used as catalyst for chemoselective Knoevenagel condensation of aromatic aldehydes and Meldrum's acid to give 5-arylidene Meldrum's acid which underwent tandem enol lactonization by Michael addition/cyclization sequence with active methylene compounds in the presence of Ni nanoparticles to give corresponding enol lactone derivatives.
- Khurana, Jitender M.,Vij, Kanika
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experimental part
p. 3666 - 3669
(2011/07/29)
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- Facile Knoevenagel and domino Knoevenagel/Michael reactions using gel-entrapped base catalysts
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An efficient method for Knoevenagel condensation of arenecarbaldehydes with active methylene compounds such as barbituric acid and Meldrum's acid in the presence of gel-entrapped base catalysts is reported. The method has been extended to the one-pot synthesis of arylmethylene-bis[3-hydroxycyclohex-2-en-1- one] derivatives from dimedone (=5,5-dimethylcyclohexane-1,3-dione) and arenecarbaldehydes by using domino Knoevenagel/Michael reaction sequence. Copyright
- Shinde, Shital,Rashinkar, Gajanan,Kumbhar, Arjun,Kamble, Santosh,Salunkhe, Rajashri
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experimental part
p. 1943 - 1951
(2012/01/04)
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- A systematic study on Knoevenagel reaction and Nazarov cyclization of less reactive carbonyl compounds using rare earth triflates and its applications
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A systematic study of Knoevenagel reaction and Nazarov cyclization was made on variety of less reactive carbonyl compounds such as β-ketoesters, 1,3-diketones and cyclic active methylene compounds using Yb(OTf)3 as the catalyst. Recycling study confirms reusability of the catalyst without much loss of activity.
- Ilangovan,Muralidharan,Maruthamuthu
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experimental part
p. 1000 - 1006
(2012/02/05)
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- Facile synthesis and biological evaluation of 3,3-diphenylpropanoyl piperazines as T-type calcium channel blockers
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We have developed a facile synthesis of 3,3-diphenylpropanamides using Meldrum's acid derivatives as amide coupling components. The in vitro biological evaluation of the title compounds led to the identification of compound 1h, which has good inhibitory a
- Choi, Yeon-Hee,Baek, Du Jong,Seo, Seon Hee,Lee, Jae Kyun,Pae, Ae Nim,Cho, Yong Seo,Min, Sun-Joon
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body text
p. 215 - 219
(2011/02/26)
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- 3-Substituted 3-(4-aryloxyaryl)-propanoic acids as GPR40 agonists
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The design, synthesis, and structure-activity relationship (SAR) for a series of β-substituted 3-(4-aryloxyaryl)propanoic acid GPR40 agonists is described. Systematic replacement of the pendant aryloxy group led to identification of potent GPR40 agonists. In order to identify candidates suitable for in vivo validation of the target, serum shifted potency and pharmacokinetic properties were determined for several compounds. Finally, further profiling of compound 7 is presented, including demonstration of enhanced glucose tolerance in an in vivo mouse model.
- Walsh, Shawn P.,Severino, Alexandra,Zhou, Changyou,He, Jiafang,Liang, Gui-Bai,Tan, Carina P.,Cao, Jin,Eiermann, George J.,Xu, Ling,Salituro, Gino,Howard, Andrew D.,Mills, Sander G.,Yang, Lihu
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scheme or table
p. 3390 - 3394
(2011/06/24)
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- Synthesis and biological evaluation of arylidene analogues of Meldrum's acid as a new class of antimalarial and antioxidant agents
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A series of arylidene analogues of Meldrum's acid were synthesized and evaluated for in vitro antimalarial and antioxidant activities for the first time. The influence of various physico-chemical parameters such as dielectric constant (), donor number (DN
- Sandhu, Harmeet S.,Sapra, Sameer,Gupta, Mukesh,Nepali, Kunal,Gautam, Raju,Yadav, Sunil,Kumar, Raj,Jachak, Sanjay M.,Chugh, Manoj,Gupta, Manish K.,Suri, Om P.,Dhar
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experimental part
p. 5626 - 5633
(2010/09/11)
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- Synthesis of zwitterionic salts of pyridinium-meldrum acid and barbiturate through unique four-component reactions
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An efficient synthetic procedure for the preparation of the unusual charge-separated pyridinium-Meldrum acid and N,N-dimethylbarbiturate acid zwitterionic salts was developed though a unique one-pot fourcomponent reaction involving pyridine, aromatic aldehyde, Meldrum acid or N,N-dimethylbarbituric acid, and p-nitrobenzyl bromide in acetonitrile. By varying combinations of four components involving nitrogencontaining heterocycles, we conveniently established reactiveα-halomethylene compounds, aldehydes and β-dicarbonyl compounds a library of zwitterionic salts.
- Wang, Qi-Fang,Hui, Li,Hou, Hong,Yan, Chao-Guo
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supporting information; experimental part
p. 260 - 265
(2010/08/05)
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- Knoevenagel condensation of aldehydes with Meldrum's acid in ionic liquids
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The Knoevenagel condensation of Meldrum's acid with aromatic aldehydes proceeded efficiently in the recyclable ionic liquid [bmim]BF4 at room temperature in the presence of catalytic amounts of piperidine.
- Tahmassebi, Daryoush,Wilson, Levi J. A.,Kieser, Jerod M.
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experimental part
p. 2605 - 2613
(2009/12/04)
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- Lewis base-promoted hydrosilylation of cyclic malonates: Synthesis of β-substituted aldehydes and γ-substituted amines
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The Lewis base-promoted hydrosilylation of cyclic malonates provides a convenient synthesis of β-substituted aldehydes. No over-reduction to the primary alcohol is observed as the aldehyde functionality is protected until a subsequent hydrolysis step. The
- Frost, Christopher G.,Hartley, Benjamin C.
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supporting information; experimental part
p. 3599 - 3602
(2009/09/05)
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- A practical synthesis of α-substituted tert-butyl acrylates from meldrum's acid and aldehydes
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An expeditious synthesis of α-substituted tert-butyl acrylates from commercially available aldehydes and Meldrum's acid has been established. The method benefits from a telescoped condensation-reduction sequence to afford 5-monosubstituted Meldrum's acid
- Frost, Christopher G.,Penrose, Stephen D.,Gleave, Robert
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experimental part
p. 627 - 635
(2009/07/03)
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- Tandem C-C bond-forming processes: Interception of the Pd-catalyzed decarboxylative allylation of allyl diphenylglycinate Lmines with activated olefins
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Interception of the Pd-catalyzed decarboxylase allylation of allyl diphenylglycinate imines with appropriately functionalized Michael acceptors, followed by Heck cyclization, allows for the efficient construction of relatively complex organoamine framewor
- Yeagley, Andrew A.,Lowder, Melissa A.,Chruma, Jason J.
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supporting information; experimental part
p. 4022 - 4025
(2009/12/05)
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- Asymmetrie addition of alkenylstannanes to alkylidene meldrum's acids
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Herein, we describe enantioselective addition of alkenyltin reagents possessing a reactive and sensitive allylic functionality not readily available to other classes of alkenyl metals. This method is enabled by the use of highly electrophilic alkylidene M
- Mahoney, Stuart J.,Dumas, Aaron M.,Fillion, Eric
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supporting information; experimental part
p. 5346 - 5349
(2010/02/28)
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- Enantioselective rhodium-catalyzed conjugate alkynylation of 5-benzylidene Meldrum's acids with TMS-acetylene
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(Chemical Equation Presented) The enantioselective alkynylation of benzylidene Meldrum's acids has been successfully achieved through rhodium-catalyzed addition of TMS-acetylene in the presence of bisphosphine ligand 3,5-Xylyl-MeOBIPHEP. The resulting Mel
- Fillion, Eric,Zorzitto, Alexander K.
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supporting information; experimental part
p. 14608 - 14609
(2010/01/06)
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- Uncatalyzed Knoevenagel condensation in PEG-600 at room temperature
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A rapid, efficient, and ecofriendly protocol has been developed for the Knoevenagel condensation of active methylene compounds with aromatic, aliphatic, conjugated and heteroaromatic aldehydes in polyethylene glycol-600 (PEG-600) with good to excellent yi
- Bandgar, Babasaheb P.,Korbad, Balaji L.,Patil, Sachin A.,Bandgar, Sunita B.,Chavan, Hemant V.,Hote, Baliram S.
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p. 700 - 703
(2008/12/22)
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- Electrophilicity parameters of 5-benzylidene-2,2-dimethyl[1,3]dioxane-4,6- diones (benzylidene meldrum's acids)
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(Chemical Equation Presented) Kinetics of the reactions of four benzylidene Meldrum's acids 1 with acceptor-substituted carbanions 2 were studied photometrically in DMSO at 20°C. The reactions follow second-order kinetics, and the second-order rate consta
- Kaumanns, Oliver,Mayr, Herbert
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p. 2738 - 2745
(2008/09/20)
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- Nucleophilicities and carbon basicities of DBU and DBN
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The nucleophilicity and Lewis basicity of DBU and DBN toward C sp2 centers have been measured: nucleophilicities increase in the series DMAP DBU DBN DABCO while Lewis basicities are DABCO DMAP DBU DBN. The Royal Society of Chemistry
- Baidya,Mayr, Herbert
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p. 1792 - 1794
(2008/12/22)
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- A general and practical preparation of alkylidene Meldrum's acids
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Although many methods have been reported for the Knoevenagel condensation of aldehydes and Meldrum's acid, most are not general or use unconventional reagents and conditions. We have found that alkylidene Meldrum's acids form readily in benzene solution u
- Dumas, Aaron M.,Seed, Adam,Zorzitto, Alexander K.,Fillion, Eric
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p. 7072 - 7074
(2008/03/11)
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- Tandem molybdenum catalyzed hydrosilylations: An expedient synthesis of β-aryl aldehydes
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The synthesis of β-aryl aldehydes utilizing a tandem molybdenum catalyzed hydrosilylation is described. This new functional group interconversion provides an efficient method for the two-carbon homologation of aryl aldehydes.
- Frost, Christopher G.,Hartley, Benjamin C.
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p. 4259 - 4261
(2008/02/12)
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- Ionic liquid-mediated knoevenagel condensation of Meldrum's acid and aldehydes
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A simple, efficient, and green protocol for Knoevenagel condensation of Meldrum's acid and aldehydes in ionic liquid at room temperature without any catalyst is described. The reaction has been performed in different ionic liquids. The enhancement in the
- Darvatkar, Nitin B.,Deorukhkar, Amol R.,Bhilare, Sachin V.,Salunkhe, Manikrao M.
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p. 3043 - 3051
(2007/10/03)
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- Modular synthesis of tetrahydrofluorenones from 5-alkylidene Meldrum's acids
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The one-pot synthesis of tetrahydrofluorenones, the core 6-5-6 tricyclic structural motif found in norditerpenoid natural products, from alkylidene Meldrum's acids via thermal Diels-Alder/BF3·OEt 2-catalyzed Friedel-Crafts acylation
- Fillion, Eric,Dumas, Aaron M.,Hogg, Sylvia A.
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p. 9899 - 9902
(2007/10/03)
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- Organic reactions in ionic liquids: Ionic liquid ethylammonium nitrate-promoted knoevenagel condensation of meldrum's acid with aromatic aldehydes
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The Knoevenagel condensation of Meldrum's acid with aromatic aldehydes proceeded efficiently in a reusable ionic liquid, ethylammonium nitrate, at room temperature in the absence of any catalyst with high yields. Copyright Taylor & Francis, Inc.
- Hu, Yi,Wei, Ping,Huang, He,Le, Zhang-Gao,Chen, Zhen-Chu
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p. 2955 - 2960
(2007/10/03)
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- One Pot Synthesis of Monoalkylated and Mixed, Dialkylated Meldrum's Acid Derivatives
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A simple one pot method, involving sequential Knoevenagel condensation of Meldrum's acid with aromatic aldehydes, conjugate reduction of ylidene Meldrum's acid using sodium borohydride followed by alkylation, to prepare mixed dialkylated derivatives of Meldrum's acid is described.
- Desai, Uday V.,Pore,Mane,Solabannavar,Wadgaonkar
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