Enantioselective Michael addition of malononitrile to chalcone with bifunctional squaramide organocatalysts

Download

index.pdf

Date

2015

Author

Sargın, Nurdan

Metadata

Show full item record

Item Usage Stats

262
views

156
downloads

4H-pyran derivatives show diverse biological activity such as antimicrobial, antibacterial, antiviral and antifungal. 4H-pyran derivatives can be synthesized easily from 2-(3-oxo-1,3-diphenylpropyl)malononitrile which is the Michael addition product of malononitrile to trans-chalcone. Synthesizing chiral biologically active compounds with metal free approach (organocatalysis) is a significant topic. In this thesis, chiral 2-(3-oxo-1,3-diphenylpropyl)malononitrile was synthesized with quinine or 2-aminoDMAP based novel bifunctional organocatalysts which were developed in our group. In the asymmetric Michael addition reaction, 2-adamantyl anchored quinine-squaramide organocatalyst was found the best among the other tested organocatalysts in the optimization reactions. Consequently, 10 different derivatives of Michael product were synthesized up to 86% ee under the optimized condition with very low catalyst loading (0.5 mol%).

Subject Keywords

Asymmetric synthesis., Asymmetry (Chemistry)., Catalysis., Biocatalysis., Organocatalysis., Enantioselective catalysis.

URI

http://etd.lib.metu.edu.tr/upload/12618394/index.pdf
https://hdl.handle.net/11511/24391

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Enantioselective synthesis of new chiral 2-aziridinyl phosphonates and studies of their biological activities Doğan, Özdemir; Beksultanova, Nurzhan; ALTANLAR, NURTEN; Simsek, Duygu; KARABIYIK, HASAN (2017-02-15) A new series of chiral aziridinyl phosphonates has been synthesized and evaluated for antibacterial and antifungal activities. For the synthesis, a Gabriel-Cromwell reaction was used to form aziridinyl phosphonates in 52-83% yield. In order to evaluate antibacterial and antifungal activities, MIC values were measured. Although most of the compounds showed insignificant activity, two of them provided low to moderate antifungal activity.
Enzymatic extraction of activated sludge extracellular polymers and implications on bioflocculation Sesay, Ml; Özcengiz, Gülay; Sanin, Faika Dilek (Elsevier BV, 2006-04-01) This study examines enzyme hydrolysis, a mild, effective, but a rarely used method of extracellular polymer extraction, in removing polymers from mixed culture activated sludge flocs. Two carbohydrate specific enzymes (a-amylase and cellulase) and a protein specific enzyme (proteinase) are used during the study. First, the kinetic aspect is investigated, then enzyme dose optimization is carried out on laboratory grown activated sludge samples cultured at solids retention times (SRT) of 4 and 20 days. A more...
Water soluble nickel(0) and cobalt(0) nanoclusters stabilized by poly(4-styrenesulfonic acid-co-maleic acid): Highly active, durable and cost effective catalysts in hydrogen generation from the hydrolysis of ammonia borane Metin, Onder; Özkar, Saim (2011-01-01) This paper reports the in-situ generation and catalytic activity of nickel(0) and cobalt(0) nanoclusters stabilized by poly(4-styrene sulfonic acid-co-maleic acid), PSSA-co-MA, in the hydrolysis of ammonia borane (AB). PSSA-co-MA stabilized nickel(0) (PSMA-Ni) and cobalt(0) nanoclusters (PSMA-Co) having average particle size of 2.1 +/- 0.6 and 5.3 +/- 1.6 nm, respectively, were generated by in-situ reduction of nickel(II) chloride or cobalt(II) chloride in an aquoues solution of NaBH(4)/H(3)NBH(3) in the pr...
Collagen-chondroitin sulfate-based PLLA-SAIB-coated rhBMP-2 delivery system for bone repair Keskin, Dilek; Tezcaner, Ayşen; Hasırcı, Vasıf Nejat (2005-06-01) Bone morphogenetic proteins (BMPs) are osteoinductive proteins used intensively in clinical investigations involving various bone-related treatments. Owing to their high potential in new bone formation they require local application at the treatment site. For this purpose various controlled delivery systems with BMPs as the excipients have been prepared in recent years. Focusing on this clinical need a disc-shaped BMP carrier was designed as a local delivery system using soluble collagen and chondroitin sul...
Enantioselective michael addition of 1-nitropropane to nitroolefins with 2-aminodmap and quinine based bifunctional organocatalysts Kanberoğlu, Esra; Tanyeli, Cihangir; Department of Chemistry (2015) 1,3-dinitro compounds are key materials in the synthesis of a variety of important fine chemicals. Moreover, they are reduced to 1,3-diamines which are starting materials of biologically active compounds, agrochemicals and pharmaceuticals. In this study, ((2S,3S)-1,3-dinitropentan-2-yl)benzene was synthesized via the Michael addition of 1-nitropropane to trans-β-nitrostyrene in the presence of chiral bifunctional 2-aminoDMAP and quinine based organocatalysts. In the first part of study, reaction conditions ...

Citation Formats

N. Sargın, “Enantioselective Michael addition of malononitrile to chalcone with bifunctional squaramide organocatalysts,” M.S. - Master of Science, Middle East Technical University, 2015.