1. Explain why methanol is chosen as the solvent for the extraction
a. Methanol was chosen as a solvent because it is highly polar due to its functional groups. The compound used in this experiment was aspirin, which is also polar because of its functional groups. Two polar substances will dissolve within each other. Additionally methanol was chosen because it has a moderate boiling point of approximately 64 degrees Celsius. This boiling point allows the solvent to be evaporated at a moderate speed that is most effective for the experiment. The steady evaporation aides in the recrystallization and purification of the compound.
2. What is the role of the alumina column?
a. The alumina column acted as the stationary phase in the chromatography
In a separate beaker, acetone (0.587 mL, 8 mmol) and benzaldehyde (1.63 mL, 16 mmol) were charged with a stir bar and stirred on a magnetic stirrer. The beaker mixture was slowly added to the Erlenmeyer flask and stirred at room temperature for 30 minutes. Every 10 minutes, a small amount of the reaction mixture was spotted on a TLC plate, with an eluent mixture of ethyl acetate (2 mL) and hexanes (8 mL), to monitor the decrease in benzaldehyde via a UV light. When the reaction was complete, it was chilled in an ice bath until the product precipitated, which was then vacuum filtrated. The filter cake was washed with ice-cold 95% ethanol (2 x 10 mL) and 4% acetic acid in 95% ethanol (10 mL). The solid was fluffed and vacuum filtrated for about 15 minutes. The 0.688 g (2.9 mmol, 36.8%, 111.3-112.8 °C) product was analyzed via FTIR and 1H NMR spectroscopies, and the melting point was obtained via
Solid triphenylmethanol (0.200 g, 0.768 mmol) and sulfuric acid (2 mL) were added to a reaction tube, which was then ground using a glass rod until it dissolved and turned a dark orange color. The mixture was then added dropwise via a glass pipette into another reaction tube containing methanol (1 mL). An extra amount of methanol (2 mL) was used to transfer the rest of the contents of the first reaction tube. Formation of crystals was facilitated by scratching the side of the tube and adding additional methanol until the color changed to an off-white color. The contents of the tube were then vacuum filtered with water and the resulting crude product was weighed and then recrystallized using hot methanol to form triphenylmethyl methyl ether (0.051 g, 0.186 mmol, 24.2%). The melting point was 81 – 83˚
The experimental Fischer esterification of 8.92g of acetic acid with 5.0g of isopentyl alcohol using concentrated sulfuric acid as a catalyst yielded 4.83g (65.3% yield) of isopentyl acetate. The product being isopentyl acetate was confirmed when the boiling point during distillation had similar characteristics to that of the literature boiling points2. Physical characteristics like color and smell also concluded a match of our product with what was intended. 1H-NMR spectroscopy analysis supported this claim due to the fact that the integration values and chemical shifts were comparable to isopentyl acetate. Lastly, infrared spectroscopy (IR) showed similar key characteristics of our product’s wavelengths to that of pure isopentyl acetate5.
The alcohol starting material, 2-methylcyclohexanol, was dehydrated through an E1 elimination by using of phosphoric acid as a catalyst. After a purification by simple distillation, which removed the alkene product and the by-product water from the reaction mixture, the methylcyclohexene products were analyzed by percent yield, boiling point, IR spectroscopy, and two chemical tests, Br2 in CCl4 and Jones test. By performing the simple distillation using pyrolysis, 85% of phosphoric acid and 2-methylcyclohexanol were added into the boiling flask, where the product from the collecting flask was condensed by the ice, and washed with the saturated sodium chloride. The weight of the product was determined and the percent yield of the product was
Aspirin was prepared according to the protocol provided on Blackboard. The three sections to this experiment were 1. Synthesis of Aspirin, 2. Recrystallization of Aspirin, and 3. Characterization of Aspirin.
Craig, D. Q. (2002). Pharmaceutical Applications of Micro-Thermal Analysis. Journal of Pharmaceutical Science, 91(5), 1201-1213.
Esterification was used to synthesize aspirin which was by reacting salicylic acid with acetic anhydride. To speed up the reaction, dehydrating agent and conc. sulphuric acid was present. The purity of a substance, which is the aspirin in this particular experiment, can be determined by the identification of its melting point.
The purpose of this lab was to show us what happens to the egg (that was in vinegar), and corn syrup when you combine it. The egg that was in the corn syrup overnight was shriveled.
You have been asked to design an oral liquid formulation of ibuprofen for paediatric use.
Alternative energy is the world’s race as of now. As the space race concluded and the nuclear arms race died down, alternative energy became the race of the ages. In today’s society, with today’s technology there are all sorts of forms of alternative energies. These energies include hydro power, geothermal, biomass, nuclear power, and so much more. With all of these variations of alternative energy the question now becomes, which form is the best to use? Are any of them safe? Which ones would effectively solve the world’s depleting energy crisis? Of course, the country that is able to produce clean efficient energy; that country would become the new world power virtually overnight. With today’s technology, should we resort to food/corn as our primary source of energy?
The purpose of this experiment was to learn and preform an acid-base extraction technique to separate organic compounds successfully and obtaining amounts of each component in the mixture. In this experiment, the separation will be done by separatory funnel preforming on two liquids that are immiscible from two layers when added together. The individual components of Phensuprin (Acetylsalicylic acid, Acetanilide, and Sucrose as a filler) was separated based upon their solubility and reactivity, and the amount of each component in the mixture was obtained. Also, the purity of each component will be determined by the melting point of the component.
In this experiment, a mixture of three substances (benzoic acid, 2-naphthol, and 1-4 dimethoxybenzene) will be separated based off acidity strength using the liquid-liquid extraction technique through a separatory funnel. Benzoic acid and 2-napthol will be converted into ionic salts when reacting with their appropriate bases (sodium bicarbonate and sodium hydroxide). Both ionic salts will then form solids through the addition of acidic HCl. Neutral 1,4 – dimethoxybenzene forms a solid through the evaporation of ether. Each compound will then be purified through recrystallization, using the processes of dissolving the solid in either water or methanol, and isolating the solid through vacuum filtration. After a week of evaporation, the compounds will then be examined for both
Background Information Aspirin is an analgesic (pain relieving) and an antipyretic drug (a drug that lowers body temperature). The main constituent of aspirin is 2 - ethanoythydroxybenzoic acid, also known as acetylsalicyclic acid (shown below right). It was originally made from just salicylic acid (which is found in the bark of a willow tree) when used by the Ancient Greeks to counter fever and pain, but its bitterness and tendency to irritate the stomach caused problems. These were resolved by the German chemist Felix Hoffman, who made the acetyl derivative of salicylic acid in the
Methanol was the most polar among 3 alcohols used in this part, hence was soluble in water as both water and methanol were polar. However, methanol was partially soluble in hexane because the Van der Waals interaction between methanol
One drop of the liquid (L21) was placed in a test tube. But for the solid unknown (S21) 5mg was added to the test tube. 0.5mL of acetone was added with 1 drop of jones reagent. The results were recorded. The test tubes were then discarded in the hazardous waste container.