It was found that nonpolar hexanes and toluene are bad solvents for this reaction, since no epoxide could be obtained in these two solvents entries 12. Immobilization of chiral quininium salt in ionic liquid. In conclusion, we have developed an efficient epoxidation of cinnamates and chalcones, in particular chiral. Onepot synthesis of chalcone epoxidesa green chemistry. Asymmetric epoxidation of chalcone catalyzed by reusable polylleucine immobilized on hydrotalcite. Immobilization of chiral quininium salt in ionic liquid for enantioselective epoxidation of chalcones. For example, students may collect an ir spectrum of their chalcone product while the 1h nmr can be provided in the laboratory manual.
Arylidene derivatives as synthons in heterocyclic synthesis. I salem and others published some reactions of chalcone epoxides. You may see the transition state by clicking the change equation button. Fructul interzis nedjma pdf does a good job in many ways, and while it fructul interzis nedjma still a new platform and growing, it has potential. Baal 4 o 7, chalcone, epoxidation, fe doped barium aluminate. View enhanced pdf access article on wiley online library html view download pdf for offline viewing.
Go to the publishers online edition of synthetic communications to view the free supplemental file. Indiumiii chloride catalyzes regioselective ring opening of chalcone epoxides. Be sure to calculate the theoretical yield of the product. A polypeptidecatalyzed asymmetric epoxidation of e chalcone using h 2 o 2. Chemical and structural properties of chalcones i fabad journal. In recent years, microwave assisted solid support solvent free organic synthesis have attracted the attention as they offer several advantages such as simple procedure, fast reaction rate, mild reaction conditions, ecofriendly.
Highly enantioselective epoxidation with hydrogen peroxide and. Epoxidation of chalcone in the second step using 30% naoh 3 molar equiv and 30% h 2 o 2 5 molar equiv afforded the final epoxide in 90% yield. Chalcone is an aromatic ketone and an enone that forms the central core for a variety of important biological compounds, which are known collectively as chalcones or chalconoids. Consequently, epoxidations by peracids always have synstereoselectivity, and seldom give structural rearrangement. Somewhere in one of your exams, you will see at least one question on epoxidation of alkenes. Pdf file of the digital annex containing additional nmr, gc and hplc spectra. Efficient epoxidation of chalcones with ureahydrogen peroxide under ultrasound irradiation article in ultrasonics sonochemistry 163. The lab will use onepot consecutive reactions of claisen schmidt condensation and epoxidation to prepare chalcone. Up to 92% ee was obtained for epoxidation of chalcones using catalyst a. The overall yield of chalcone epoxide obtained from the twostep method was calculated to be 83%.
An interesting tendency can be found in the asymmetric epoxidation of chalcones using cinchonaptcs. Chalcone was formed from substituted benzaldehyde archo and acetophenone arcoch. The reaction was reported by sebastian julia at the chemical institute of sarria in 1980, with further elaboration by both julia and stefano colonna. Onepot synthesis of chalcone epoxides via claisen schmidt. Epoxidation reaction has recently been the subject of numerous investigations and a number of. A cinchonaptc with free hydroxy group at c9 position generally provides better enantioselectivity when an alkaline peroxide is used as the oxidant. Kinetic analysis of chalcone epoxidation in a biphasic system wai wing leung and ruben m. The asymmetric epoxidation of several chalcones and other electronpoor olefins, in the presence of catalytic amounts of polysaminoacids in a triphase system with optical yields of up to 96%. Highly stereoselective epoxidation of chalcone in a triphasic toluenewaterpolysalanine system. Studies in asymmetric epoxidation of chalcone using. Efficient epoxidation of chalcones with ureahydrogen.
The solventfree synthesis of 20 chalcones was carried out by grinding the benzaldehyde unsubstituted, 4methyl, 4methoxy, 3chloro, or 4chloro and the acetophenone unsubstituted, 4methyl, 4bromo, or 4methoxy in the presence of solid sodium hydroxide with a mortar and pestle. The epoxidation reaction is believed to occur in a single step with a transition state incorporating all of the bonding events shown in the equation. Alternative names for chalcone include benzylideneacetophenone, phenyl styryl ketone, benzalacetophenone. In this study, fe doped barium aluminate nano powder has been synthesized via homogeneous precipitation method and was investigated for its activity on the epoxidation chalcone with hydrogen peroxide as a pure oxidant. By using trans chalcone 2a as the model compound and 1. An excellent example is the reaction of chalcone with h2o2naoh in the three. Pdf phase transfer catalyzed asymmetric epoxidation of. Solventfree synthesis of chalcones journal of chemical. An epoxide is a 3membered ring containing two carbon atoms and one oxygen atom. Phasetransfer catalyzed asymmetric epoxidation of chalcones using chiral crown ethers derived from dglucose, dgalactose, and dmannitol.
Kinetic analysis of chalcone epoxidation in a biphasic system. Pdf studies in asymmetric epoxidation of chalcone using. The epoxidation of trans chalcones proceeds under mild conditions at room temperature in alkaline solution to afford the corresponding epoxides in excellent yields using trans3,5dihydroperoxy3,5dimethyl1,2dioxolane as an efficient oxygen source. The kinetics of chalcone formation via aldol condensation was studied using uv spectrophotometry. Solventfree synthesis of zeolites from anhydrous starting raw solids chemoselective. Epoxidation is the chemical reaction which converts the carboncarbon double bond into oxiranes epoxides, using a variety of reagents including air oxidation, hypochlorous acid, hydrogen peroxide, and organic peracid fettes, 1964. Highly efficient epoxidation of chalcone using fe doped. It is a member of styrenes and a member of chalcones.
Although the crude chalcone is often found to have sufficient purity for product. Request pdf onepot synthesis of chalcone epoxides a green chemistry strategy waste minimization is a very important aspect of an environmentally. The julia colonna epoxidation of a chalcone proceeds with polylleucine and hydrogen peroxide in generic triphasic conditions. Reaction progress kinetic analysis of the polylleucine pllcatalyzed epoxidation of substituted chalcones 1a. Pdf asymmetric epoxidation of chalcone catalyzed by. Organocatalytic asymmetric epoxidation and aziridination. The julia colonna epoxidation is an asymmetric polyleucine catalyzed nucleophilic epoxidation of electron deficient olefins in a triphasic system. Chalcones and chalcone epoxides are important classes of organic compounds with distinct structural features and high. Asymmetric epoxidation of transchalcones derivatives with different tetraaminodentate. Studies in asymmetric epoxidation of chalcone using quaternary salts and nonionic surfactants based on 6amino6deoxyglucose as chiral phase transfer catalysts. Many students like to remember it as a cyclic ether. Part ii find, read and cite all the research you need on researchgate.
Asymmetric epoxidation of cinnamic acid derivatives by in. Mechanistic insights from reaction progress kinetic. Butyl hydroperoxide in the presence of a cobaltii schiff base complex. Epoxidation of chalcones 1 with ureahydrogen peroxide uhp under ultrasound irradiation gave oxirane derivatives. Cdr file converter to pdf free download defense of poesy sidney pdf download epoxidation of chalcones pdf download padberg elementare. Chalcones belong to the flavonoid family and display several. The procedure involves grinding acetophenone with one equivalent of sodium hydroxide and benzaldehyde derivative for ten minutes using a mortar and pestle.
Savizky department of chemistry, the cooper union for the advancement of science and art, 41 cooper square, new york, new york 3, united states. Highly stereoselective epoxidation of chalcone in a triphasic toluene. Experiment 62 in pavia 5th edition, prelab include the usual prelab components, chemical equation, and a detailed reagent table. Enantioselective epoxidation of electrona wiley online library. The foamy structure apparently is responsible for uv absorption, and the ceria foam is basic enough to promote the epoxidation of chalcone. Asymmetric epoxidation, chalcone, quaternary sugar salts, nonionic surfactants introduction although, sharpless paved the way for much of todays catalytic asymmetric syntheses1, the use of phasetransfer catalysts in asymmetric synthesis was described 26 in the mid1970s. Pdf phasetransfer catalyzed asymmetric epoxidation of. This organic chemistry video tutorial provides a basic introduction into the epoxidation of alkenes with peroxy acids such as. Each chalcone is then isolated by suction filtration after washing with water.
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