Laboratory session 1: Diacetylcaffeic acid → Diacetylated CAPE The millimoles of 2g of diacetylcaffeic acid starting material was calculated. The amount of oxalyl chloride (in grams and millimoles) to be added was also calculated. This was calculated by every millimole of diacetylcaffeic acid present, 2 equivalent amount of oxalyl chloride was needed. Step 1: The diacetylcaffeic acid was transferred into pre-weighed (66.16g) 100cm3round-bottom flask and the mass after the transfer (68.16g). 20cm3 dichloromethane was added into the flask and the flask was clamped into an ice bath on top of a stirrer hotplate, ensuring the heater remained off. The calculated oxalyl chloride amount was added by a demonstrator utilising an adjustable autopipette. …show more content…
Further addition of 10cm3of ethyl acetate to the original flask to ensure all material has dissolved. 2 separate additions of 50cm3of water was used added to wash the organic solution, then 2 separate additions of 50cm3of brine. The flask would form 2 layers where the bottom aqueous layer was to be filtered out, keeping the organic top layer. Magnesium sulphate was added to the organic solution to dry in a pre-weighed flask (65.61g). The rotary evaporator was used to remove any ethyl acetate only when the organic solution has dried with no clumping. Mass of material and appearance was recorded (mass of flask before ethyl acetate evaporation: 43.31g and mass of flask after ethyl acetate evaporation: 66.81g with a creamy/mushy appearance). Analysis of the material via infrared spectroscopy was carried out, also establishing its melting point (87°C) Laboratory session 3: Diacetylated CAPE→ CAPE Ethyl acetate was used to dissolve small amount of acetylated CAPE crystals. A 2cm thin layer chromatography (TLC) plate and 50:50 ethyl acetate solvent was used to analyse the crude ester product against diacetylcaffeic acid for …show more content…
A 5cm TLC plate was marked with 0, 15, 30, 45 and 60 minutes respectively on the baseline. 300 mg of ester material was placed in a 50cm3 round bottomed flask. 5cm3 of methanol and dichloromethane was added to dissolve the material spotted at time 0 on the TLC plate. 225mg of potassium carbonate was further added to the solution. Each time intervals were spotted respectively, whilst the reaction was mixed at room temperature. Only after all time points were spotted was the plate ran using 50:50 ethyl acetate as the solvent. Rotary evaporator was used to remove the solvents after confirming absence of diacetylated CAPE. 20cm3of ethyl acetate dissolved any remaining residues and transferred to a separating funnel. The organic solution was washed with water by adding 2 separate 20cm3of water and filtering water out after each addition. Then 2 further separate additions of brine measuring 20cm3each and again filtering brine to retain only the organic solution. Magnesium sulphate dried the organic solution and filtered into a pre-weighed (66.24g) 100cm3round bottom flask to remove ethyl acetate with the rotary evaporator. A vacuum desiccator was used to dry the material for
0.98 grams of Camphor was dissolved in 15 mL of ethanol. 1.055 grams of sodium borohydride was added was slowly added to the mixture. The mixture was left standing for ten minutes then it was heated to boiling. 5.00 mL of ethanol was added to keep the volume during the hot water bath. The mixture was then poured into 100mL of ice water. A white precipitant was formed immediately. The solid was recrystallized in a water and ethanol solution. 1.65 grams of product was measured after filtration and drying. 1mL of the counter-solvent, water, was added to the
Prepare a drying filter using filter flask, Hirsch funnel with filter paper, and 2 g anhydrous sodium sulfate.
Wash (swirl and shake) the organic layer with one 10-mL portion of water and again drain the lower aqueous layer. Transfer the organic layer to a small, dry Erlenmeyer flask by pouring it from the top of the separatory funnel. Dry the crude t-pentyl chloride over 1.01 g of anhydrous calcium chloride until it is clear (see Technique 12, Section 12.9). Swirl the alkyl halide with the drying agent to aid the drying.
In addition, the diethyl ether solution was decanted into the round bottom flask (50 mL). Afterwards, the washed Na2SO4 and the Erlenmeyer flask with additional diethyl ether (5 mL) was added to the round bottom flask, mentioned earlier. Later, the round bottom flask was placed in the rotary evaporator. In addition, the acetanilide flask and 3-chlorobenzoic acid was weighed and tared to determine the mass. Not to mention, the mass-% of 3-chlorobenzoic acid and acetanilide was calculated. Lastly, the melting points of acetanilide and 3-chlorobenzoic acid was
The purpose is to develop an initial hypothesis after first run of TLC experiment of the unknown. The unknown solvent is used to indicate the component in the unknown. The unknown solvent was tested with 5 standards: aspirin, acetaminophen, ibuprofen, salicylamide, and caffeine absorbed the solvent of 200:1 solution of ethyl acetate. Based on the observation and calculate the retention factor for each standard to determine the possible components contain in the unknown.
As in the Chemistry 101 Lab Manual, pages 75 to 77. No changes to the procedure were made. Data and results Table 1: reagents used. Reagent MW
The purpose of this lab was accomplished by following the procedure. Our first step was to use the beaker to find the mass of two grams of Calcium Chloride and two grams of Sodium Carboante. After finding the mass, we added 40 ml of distilled water and stir it until it starts dissolving the mixture. In the third step, we waited until the mixtures was completely dissolved and then we poured the Sodium Carbonate solution
2-Methycyclohexanol (15mL) were added to H3PO4 (1mL) and H2SO4 (3 drops) in a 100mL round bottom flask. The distillation apparatus was assembled and the mixture was moderately heated to avoid bubbling during the distillation process. During this time, some of the equipment was not 100% secured, and some product was lost. Distillation was stopped when a black, oily substance started to form at the bottom of the flask. The distillate was collected in the Erlenmeyer flask, at the temperature of 109 degrees C. The organic layer was dried using the anhydrous MgSO4. The MgSO4 was filter off and the alkene mixture was collected. The liquid alkene was weigh.
.50g of CA and 50 mL of water were stirred together in a 125 mL flask with a stir bar. The mixture was heated to a gentle boil at 99 C. The CA was not fully dissolved so 40 mL of water was added in increments. When water was first added, the mixture turned white and the temperature decreased to 81C. However, the temperature went back to 99 C but the mixture stayed white. At a total of 90 mL of water, CA dissolved except for a few impurities.
The solution was poured into a 125ml separatory funnel and was extracted with three portions of 20:80 ethyl: hexanes. The organic layer (the top one) was obtained and all the organic layers were combined. The layers were washed with saturated sodium chloride in the separatory funnel. The organic solution was dried using magnesium sulfate anhydrous. The organic solution was the filtered. The
Equipment and reagents- We will use a 50mL beaker, a graduated buret, spatula, droplet applicator, 125mL Erlenmeyer flask, hot plate, and a container of
In order to ensure the most accurate data, a purification was performed by the process of recrystallization. To perform the recrystallization the powder was dissolved in a minimal amount of hot ethanol/H2O solvent that allowed the unknown powder to crystallize properly when cooled. This process allowed for the removal of soluble impurities when suction filtered. A sample of the unknown acid was weighed at 8.24 g, and it was found that 164ml of a 40% ethanol, 60% H20 solvent dissolved the 8.24 g of unknown acid when heated. The
Refluxing with anhydrous copper sulphate, alumina, aluminum chloride, P2O5 etc., and distilling under reduced pressure many times and collecting the proper fraction usually remove this. Vacuum lines are employed during purification, storage and dehydrating agent such as anhydrous alumina is added as an internal addition [44].
Half of the benzaldehyde- acetone mixture was added in one portion while stirring the solution vigorously. At this stage, a precipitated was formed after a few minutes. After 15 minutes, the remaining benzaldehyde- acetone mixture was added and the mixture was stirred for a further 30 minutes. After 30 minutes, the precipitate was collected by vacuum filtration and washed with cold water until the washings were
The filter paper inside the developing column ensures that the chamber is saturated in the vapors of the eluting solvent. It is important to have a cover on the container in order to minimize evaporation of the solvent. The best results will be obtained if the solvent is always fresh. By keeping the solvent fresh, its composition remains consistent during all of the experiments. If the solvent is given time to dry in certain spots, the homogeneity of the column is compromised.