مختبر عضوية، ملزمة ١، د. اسماء.pdf

EXPERIMENT 1 ALDOL CONDENSATION - SYNTHESIS OF DIBENZALACETONE ❖ Al Turath University ❖ College of Pharmacy ❖ Practical organic chemistry ❖ second stage ❖ Assistant lecturer : Asmaa Edrees Purpose The objectives of this experiment are to learn the aldol condensation mixture of aldehydes and ketones,...

EXPERIMENT 1 ALDOL CONDENSATION - SYNTHESIS OF DIBENZALACETONE ❖ Al Turath University ❖ College of Pharmacy ❖ Practical organic chemistry ❖ second stage ❖ Assistant lecturer : Asmaa Edrees Purpose The objectives of this experiment are to learn the aldol condensation mixture of aldehydes and ketones, which is used extensively in organic synthesis to form C-C bonds and make bigger molecules. ALDOL condensation Aldol means aldehyde and alcohol groups on the same molecule. Aldol May occur between two aldehydes (aldols) or ketones(ketols) in the presence of a catalytic base The reaction is only possible between two components having a-hydrogen· Mechanism: involves enolate formation and nucleophilic attack at a carbonyl carbon. Aldols and ketols lose water in the presence of acid-forming a-ß-unsaturated aldehydes or ketones and ß-hydroxy aldehydes or ketones Experimental: Chemicals: 1. 2. 3. 4. 5. 6. 7. Acetone, CH3COCH3 10% NaOH Benzaldehyde, C6H5-CHO 95% Ethanol, C2H5OH Materials: 1. 2. 3. 4. 5. 6. 125 mL Erlenmeyer flask 25 mL graduated cylinder thermometer Funnel filter paper ice bath Procedure: 1. Transfer 15mL of ethanol into a 125-mL Erlenmeyer flask and add 20mL of 10% NaOH to it. Using a thermometer, cool the solution to 20ºC. 2. In a medium-sized tube, mix 2mL of benzaldehyde with 15 drops of acetone, and leave it at room temperature for 5 minutes. Then, add the mixture to the ethanolNaOH solution in small portions and stir with a magnetic stirrer (if available) for 30 minutes. Chill the solution in an ice-water bath. Collect the yellow crystals by suction filtration and hand-dry them by pressing them between dry paper towels. 3. Determine the weight of the dibenzalacetone product, its melting point, and the percent yield. Return the product to your instructor.