Preparation of Dibenzalacetone by the Aldol Condensation

Preparation of Dibenzalacetone by the Aldol condensation David o Neill Date of experiment: 14/12/2011 Apparatus Steam bath, ice bath, Buchner funnel, beaker, conical flask, filter paper, TLC apparatus, Melting point apparatus Materials / chemicals Benzaldehyde, acetone, ethanolic sodium hydroxide, ethanol Introduction The synthesis of dibenzalacetone is formed from an Aldol condensation reaction. An Aldol condensation reaction is a very effective way of forming a carbon – carbon bond reaction, in which the enolate anion adds to the carbonyl group of the aldehyde. Aldol condensations are very versatile, as the enolate anion of the carbonyl compound can be added to the carbonyl carbon of another. The synthesis of dibenzalacetone is an†¦show more content†¦The mixture was warmed gently. After a few minutes a red colour had developed. Results and data Melting point The melting point of dibenzalacetone was determined using the melting point apparatus. The melting point was found to be 108 °C.the sharp melting point range indicates that the dibenzalacetone produced was very pure. Percentage yield Percentage yield of pure dibenzalacetone Final mass = 4.268 g Theoretical yield = 0.0245 M Dibenzalacetone 1M = 234.3 g Therefore 4.268 g = 0.0182 M Theoretical yield = 0.0245 due to the 1:1 ratio in the reaction scheme. Percentage yield = actual yield obtained (M)/ theoretical yield (M) x 100 Percentage yield = 0.0182/0.0245 x 100 = 74.3 % Purification analysis Melting point determination The efficacy of a recrystallisation can be concluded by a melting point. A pure compound usually has a sharp and characteristic melting point. Even small amounts of impurity may depress the melting point greatly. Generally, one crystallises to constant melting point. Therefore the melting point of a substance is an indicator of purity and also a specification for labelling many drug substances Thin layer chromatography Thin layer chromatography is a very popular and widely used for of chromatography as it gives a fast, qualitative analysis of mixtures and determination of purity ofShow MoreRelatedSynthesis of Dibenzalacetone1396 Words   |  6 PagesExperiment2: Preparation of Dibenzalacetone Aim: Using the cabon-cabon bond making ability in carbonyl chemistry, Dibenzalacetone is synthesized from 2 equivalent of benzaldehyde and 1 equivalent of acetone in a base catalyzed reaction. Physical Data1: *detailed risk and safety phrases are attached. substance Hazards, risks and safety practices MW (g/mol) Amt. Used Mol. mp (K) bp (K) density(g/cm^3) acetone R11, R36, R67, S9, S25, S26 58.08 0.24 g 0.004 178.2 329.4 0.79 benzaldehyde R22