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
Premium Aldehyde Thin layer chromatography Carbonyl
EXPERIMENT 8 THIN LAYER CHROMATOGRAPHY AND MELTING POINT DETERMINATION: DETECTION OF CAFFEINE IN VARIOUS SAMPLES Additional Resources http://orgchem.colorado.edu/hndbksupport/TLC/TLC.html http://coffeefaq.com/caffaq.html Materials Needed TLC equipment: 1 5-cm x 8-cm TLC plate‚ 2 capillary micropipettes‚ TLC tank and lid‚ ruler‚ UV lamp Extraction Equipment: spatula‚ 2 small test tubes‚ Pasteur pipet and bulb Chemicals: caffeine‚ ethanol‚ dichloromethane‚ TLC solvent (5% acetic acid in ethyl acetate)
Premium Thin layer chromatography Caffeine
chlorophyll and beta carotene from plant leaves using column chromatography. 2. To qualitatively characterise the pigments with UV-vis spectroscopy and TLC. 2. Results and discussion Isolation of beta carotene and chlorophylls by column chromatography Upon the loading of S1 (the extract of the plant leaves in hexane)‚ a yellow band appeared at the top part of the silica column immediately after the solvent level descended to just above the sand layer. This yellow band later developed to about 2 centimetres
Premium Chlorophyll Chromatography Thin layer chromatography
silica gel‚ which acts as a Lewis acid catalyst to facilitate the reaction. The reaction forms a porphyrinogen‚ which is then oxidized to the porphyrin product by atmospheric oxygen. Column chromatography is performed for the isolation and purification of tetraphenlyporphin‚ and the thin layer chromatography for analysis.It was concluded that the renention factor(Rf) of the 5‚10‚15‚20- Tetraphenylporphyrin with a percent yield of 61% Introduction: In this experiment 5‚10‚15‚20‚ tetraphenylporphyrin
Premium Solvent Thin layer chromatography Chemical reaction
IDENTIFICATION OF UNKNOWN SOLUTIONS USING TLC CHROMATOGRAPHY Purpose: To become familiar with the principles and terminology of TLC chromatography to identify an unknown molecule based on comparisons with known laboratory standards and Rf factors. Background Thin Layer Chromatography: Chromatography is a sophisticated method of separating and identifying mixtures of two or more compounds. The separation is accomplished by the distribution of the mixture between two phases: one that
Premium Thin layer chromatography Chromatography
due to the structure of disperse red 9 being more symmetrical than that of disperse blue 3 and having more nonpolar bonds. Disperse blue 3 is more polar because it has a hydroxide bond and has a larger dipole. The principle behind using column chromatography is that it separates compounds based on polarity. The alumina serves to allow for a purer separation than TLC plates because it has a more polar surface than silica gel does. The less polar dye moves first because it is not as soluble in the stationary
Premium Chromatography Thin layer chromatography Separation process
H2O CH3I Before coming to lab‚ please review the following techniques: "Reluxing a reaction‚" "Extraction and washing‚" "Drying an Organic Solvent‚" "Evaporating an Organic Solvent‚" "Analyzing a Solution by Thin Layer Chromatography (TLC)‚" "Separating Mixtures by Column Chromatography‚" and "Characterizing Compounds by IR." Notice that this lab brings together most of the techniques that we have used this semester. Then complete the following table before coming to class so that you will be prepared
Free Chromatography Thin layer chromatography Distillation
were extracted by using column chromography and alumina was used as the solvent. Solvents of different polarities were used‚ starting with the least polar‚ to extract the certain components from the leaves. They were then analyzed by using thin- layer chromatography. Procedure: The first part of the experiment dealt with breaking down the spinach leaves in a mortar and pestle. Acetone was added to this to help with the breakdown of the spinach leaves. Once the spinach leaves were broke down enough
Premium Thin layer chromatography Solvent Green
using simple distillation. The purity of the product will be characterized using percent yield‚ thin layer chromatography‚ Beer’s Law‚ and UV-vis. Beer’s law is used because in this experiment we are comparing our extraction of B-Carotene to the Stock B-Carotene. Beer’s law shows that absorbence of light at a specific wavelength is proportional to the concentration of the colored species in the solution. Thin layerChromatography is used to separate mixtures of substances into their component‚ thus allowing
Premium Thin layer chromatography Yield Stoichiometry
Column Chromatography ________________________________________________ You have already performed two chromatography experiments: gas chromatography and thin layer chromatography. All chromatography experiments involve passing a mixture of analytes through a system that includes a mobile phase and a stationary phase. The partitioning of the analytes between these two phases determines the rate at which they pass through the system‚ and (in theory) allows them to be separated from one another. Column
Premium Thin layer chromatography Chromatography Silica gel