15795-51-4Relevant academic research and scientific papers
Knoevenagel condensation of aldehydes with Meldrum's acid in ionic liquids
Tahmassebi, Daryoush,Wilson, Levi J. A.,Kieser, Jerod M.
, p. 2605 - 2613 (2009)
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.
Uncatalysed Knoevenagel condensation in aqueous medium at room temperature
Deb, Mohit L.,Bhuyan, Pulak J.
, p. 6453 - 6456 (2005)
Knoevenagel condensation of various aromatic and heteroaromatic aldehydes with active methylene compounds like malononitrile, ethyl cyanoacetamide, ethyl cyanoacetate, barbituric acids, Meldrum's acid, dimedone and pyrazolone proceeds smoothly with stirring in an aqueous medium. The reactions occur at room temperature giving excellent yields of the products. The work-up procedure is very simple and the products do not require further purification.
Uncatalyzed Knoevenagel condensation in PEG-600 at room temperature
Bandgar, Babasaheb P.,Korbad, Balaji L.,Patil, Sachin A.,Bandgar, Sunita B.,Chavan, Hemant V.,Hote, Baliram S.
, p. 700 - 703 (2008)
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
Bentonite catalyzed an efficient and green synthesis of arylidene meldrum's acid derivatives in aqueous media
Yahyazadehfar, Mahdieh,Ahmadi, Sayed Ali,Sheikhhosseini, Enayatollah,Ghazanfari, Dadkhoda
, p. 513 - 519 (2021/07/25)
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
Enantioselective Ammonium Ylide Mediated One-Pot Synthesis of Highly Substituted γ-Butyrolactones
Drennhaus, Till,?hler, Laura,Djalali, Saveh,H?fmann, Svenja,Müller, Clemens,Pietruszka, J?rg,Worgull, Dennis
supporting information, p. 2385 - 2396 (2020/04/30)
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.).
Boron/zinc exchange for the conjugate arylation of unsaturated Meldrum's acid derivatives
Jardim, Micaela,Baldassari, Lucas L.,Contreira, Maria Eduarda,Moro, Angélica V.,Lüdtke, Diogo S.
supporting information, (2020/01/31)
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.
An alternative, practical, and ecological protocol for synthesis of arylidene analogues of Meldrum’s acid as useful intermediates
Khaligh, Nader Ghaffari,Mihankhah, Taraneh,Johan, Mohd Rafie
, (2019/03/17)
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
Microwave-associate synthesis of Co3O4 nanoparticles as an effcient nanocatalyst for the synthesis of arylidene barbituric and Meldrum's acid derivatives in green media
Yahyazadehfar, Mahdieh,Sheikhhosseini, Enayatollah,Ahmadi, Sayed Ali,Ghazanfari, Dadkhoda
, (2019/08/02)
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.
A transition metal free expedient approach for the C[dbnd]C bond cleavage of arylidene Meldrum's acid and malononitrile derivatives
Suresh, Muthiah,Kumari, Anusueya,Singh, Raj Bahadur
, (2019/09/10)
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.
Water assisted and choline chloride-dimethylurea deep eutectic salts as catalyst towards the attractive reaction of indole, benzaldehyde, and malononitrile
Ruan, Hongli,Lv, Yue,Yu, Shijun,Lv, Chengwei,An, Yue
, p. 1266 - 1274 (2018/08/06)
The condensation of indole, benzaldehyde, and malononitrile was relatively rigorous compared with other Yonemitsu type reaction. We described a strategy using catalytic amount of choline chloride-dimethylurea deep eutectic salts as cheap and safe accelerator. We also found that introducing right amount of water in reaction system was crucial. This method tolerates variations in all three components to get desired 3-substituted indoles in satisfactory yields.
