Claisen schmidt reaction of benzaldehyde and acetone. Ochem lab report 1 2022-10-13

Claisen schmidt reaction of benzaldehyde and acetone Rating: 6,2/10 170 reviews

The Claisen-Schmidt reaction is a type of condensation reaction that occurs between a ketone or aldehyde and an ester, leading to the formation of a beta-keto ester or a beta-diketone, respectively. This reaction is named after the German chemists, Rainer Ludwig Claisen and James Schmidt, who first described it in 1887.

One of the most commonly used variations of the Claisen-Schmidt reaction is the reaction between benzaldehyde and acetone, which results in the formation of 3,4-diphenyl-2-butanone, also known as diacetylbenzene. This reaction is an example of aldol condensation, as it involves the formation of a new carbon-carbon bond between the aldehyde group of benzaldehyde and the ketone group of acetone.

The reaction between benzaldehyde and acetone can be carried out in the presence of a base, such as sodium hydroxide or potassium hydroxide, to facilitate the elimination of water as a byproduct. The base also serves to deprotonate the aldehyde and ketone, making them more reactive towards each other. The reaction is typically carried out in a solvent, such as ethanol or water, and is usually heated to a temperature of around 80-100 degrees Celsius.

One of the main advantages of the Claisen-Schmidt reaction is its high yield, as it usually produces products in yields of up to 95%. This makes it an attractive synthetic method for the preparation of a variety of compounds, including pharmaceuticals, fragrances, and flavorings.

In conclusion, the Claisen-Schmidt reaction is a useful chemical transformation that allows the synthesis of various compounds, including 3,4-diphenyl-2-butanone, through the condensation of a ketone or aldehyde with an ester. Its high yield and versatility make it a valuable tool in the field of organic chemistry.

Benzaldehyde Claisen

claisen schmidt reaction of benzaldehyde and acetone

Aqueous sodium hydroxide produces a hydroxide ion and it attacks α hydrogen in acetone to form water. If the product fails to crystallize, open the tube and scratch the inside of the tube with a glass rod. Recrystallization was determined by suction filtration and with a Hirsch funnel. A generic example of an aldol condensation is shown in Figure 1. The Claisen-Schmidt reaction, a base-catalyzed crossed aldol condensation reaction between an aldehyde or ketone containing an hydrogen with an aromatic carbonyl compound without an hydrogen, can be used to synthesize dibenzalacetone. Cross-aldol condensation reactions are a particularly useful method to synthesize new bonds and create bioactive compounds such as pyrimidine derivatives, and 1,3-diaryl-2-propenones.

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Claisen

claisen schmidt reaction of benzaldehyde and acetone

Introduction: The ability to synthesize new carbon-carbon bonds and alter the carbon skeleton of molecule is crucial to the practical application of organic chemistry. The product, dibenzalacetone, crystallizes after a few minutes. Rate this post BACKGROUND Principle: When an ethanolic solution containing acetone and its two equivalents of benzaldehyde is made alkaline with sodium hydroxide, rapid condensation occurs with the formation of dibenzal-acetone, or dibenzylidene-acetone. We used 5 of benzaldehyde, 1 of acetone which gives us a total of 6. In this experiment, acetone is deprotonated by sodium hydroxide, forming a nucleophilic enolate that can then attack the electrophile, benzaldehyde.

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LAB 2.2 opportunities.alumdev.columbia.edu

claisen schmidt reaction of benzaldehyde and acetone

Then add the previously prepared alkaline ethanolic solution and stir the mixture for 15 min at 20-25 °C external cooling may be necessary. Acetone is converted into a nucleophilic form to initiate the reaction. The solution was filtered through a Hirsch funnel and crystals were allowed to dry three minutes after they appeared to be dry, then collected. The hydroxide ion removes. Procedure- The procedure was carried out as written in the laboratory manual on page 76-78.

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Why Benzaldehyde and acetone can't do self

claisen schmidt reaction of benzaldehyde and acetone

The absence of hydrogens in benzaldehyde prevented self-aldol additions and allows for a better yield of the product. This reduces the number of possible aldol products to two- one being the crossed aldol while the other is self-condensation product obtained from the enolisable carbonyl compound. Experimental procedure A Preparation of E-4-phenylbut-3-en-2-one benzylideneacetone Pour 4. Dibenzalacetone was purified through a recrystallization process and melting points were measured. The resulting precipitate was washed with 2 mL ice cold water, which was subsequently extracted and put into a waste test tube. An aldol reaction is comprised of two parts: an aldol addition and dehydration.

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Aldol Condensation Lab Report

claisen schmidt reaction of benzaldehyde and acetone

. The melting point, both theoretical and actual was imperative in knowing if there were impurities or not. An aldol reaction is comprised of two parts: an aldol addition and dehydration. Product was weighed and then the melting point was measured. The melting point was around 110°C which is accurate in the textbook. Once precipitate dissolved, the test tube was removed from hot bath, cooled to room temperature for over five minutes, then placed in an ice bath for ten minutes to allow for crystal formation.

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Ochem lab report 1

claisen schmidt reaction of benzaldehyde and acetone

Dibenzalacetone is a chemical compound commonly found in sunscreens and some medications. Weight of Acetone 0 g Moles of Acetone 0 Moles Limiting Reagent Benzaldehyde Theoretical Moles of Product 0 Moles Theoretical Weight of Product 0 g Weight of Recrystallized Product 0 g Moles of Recrystallized Product 0 Moles Percent Yield of Recrystallized Product 84% Melting Point of Recrystallized Product 106. Its special properties indicate why it is used in sunscreens and sunblock preparations. REQUIREMENTS Chemicals: Benzaldehyde — 10 ml Acetone — 4 ml Methylated spirit — 10 ml 10% aqueous sodium hydroxide solution- 2 ml Apparatus: Conical flask or wide mouthed bottle Beaker Measuring cylinder Buchner funnel etc PROCEDURE About 10 ml 10. The O 2 on benzaldehyde attracts a proton from the water molecule to form an intermediate.

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▷ Claisen

claisen schmidt reaction of benzaldehyde and acetone

The intermediate product, β-hydroxyenolate, rapidly undergoes dehydration to give dibenzalacetone, an α, β-unsaturated carbonyl. This can be seen in Table 1. Dur to this, it was extracted via Hirsch funnel and discarded. This is a particular example of Claisen Reaction as Claisen showed that aldehyde under the influence of sodium hydroxide condenses with i another aldehyde, or ii a ketone, with the elimination of water. CHE 224 Aldol Condensation Lab Report Abstract : The purpose of the Aldol Condensation experiment was to introduce the concept of the carbon-carbon bond formation reaction and to understand the basic mechanism of the aldol condensation reaction. A yellow solid is obtained that is ethyl acetate or ethanol 2.

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Synthesis of Dibenzal Acetone from Benzaldehyde by Claison Schmidt Reaction

claisen schmidt reaction of benzaldehyde and acetone

This allowed us to determine the purity of the product. The benzalacetone, once formed, can then easily react with another mole of benzaldehyde to give the product, dibenzalacetone. Answer and Explanation: 1 In the Claisen-Schmidt reaction between Benzaldehyde and Acetone, the process is to add the Acetone in small parts to a mixture of the Benzaldehyde and the aq. El aducto inicial de aldolización no puede ser aislado ya que deshidrata espontáneamente bajo las condiciones de reacción. In the second part, benzaldehyde is present in a double excess. During this α, β-unsaturated ketones are synthesized by the process of condensation between a ketone with an aromatic aldehyde.

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