Preparation of Dibenzalacetone by the Aldol Condensation

Melting Point Data Table Compound Aspirin Caffeine Salicylamide Actual MP (ºC) 93 - 98 260 - 262 96 - 102 Expected MP (ºC) 135 236 140 Percent Error (%) ~30% ~12% ~30%

Objective: The objective of this lab is to observe the synthesis of 1-bromobutane in an SN2 reaction, to see how a primary alky halide reacts with an alcohol.

Adsorption chromatography occurs when “one substance form[s] some sort of bonds to the surface of another one”, creating intermolecular forces between the two substances (Chemguide). For thin layer chromatography, the components of the mixture are adsorbed onto the stationary phase that covers the plate (Chemguide). The more polar a substance is, the more strongly adsorbed it is (Chemguide) and the strong intermolecular forces then result in a slower rate of migration with respect to the moving phase. As the solvent touches the TLC plate, the solute (mixture) is allowed to move up the TLC plate

In determining the melting point range of the aspirin, a capillary tube (sealed at one end) was one-third-filled with the dried aspirin. The capillary tube and a thermometer were immersed in an oil bath. The temperature at which the solid started to melt and the temperature when the entire sample was completely liquefied were recorded as the melting point temperature range.

In the formation of stilbene dibromide, there are three possible products. The first is meso-stilbene dibromide in which the bromines are on opposite sides of the former double bond. The other two products, d-stilbene dibromide and L-stilbene dibromide, are enantiomers with the two bromines on the same side of the former double bond. As enantiomers, d-stilbene dibromide and L-stilbene dibromide are non-superimposable mirror images of each other. Meso-stilbene dibromide makes up 90% of the yield of this reaction, while d-stilbene dibromide and L-stilbene dibromide make up only 10%.

Condensation reaction is a chemical reaction that joins two reactants to form a larger molecule with the loss of a small molecule, usually water. 1 This reaction is used as a basis for many important process in the plastic/food industry. The most common being the formation of ester, also known as esterification. When a carboxylic acid is reacted with alcohol in the presence of a dehydrating agent, ester and water molecule are formed as products:

Abstract: Using hypochlorous acid to convert secondary alcohol called cyclododecanol to the corresponding ketone which is cyclododecanone by oxidation.

The cyclic ketone cyclohexanone was oxidized to adipic acid using the oxidizing agent nitric acid. The experiment yielded 0.2667 grams of adipic acid, giving a percent yield of 113.97%. Although the product was allowed to dry for one week, residual moisture was still present in the sample and a melting point could not be obtained. This error in the experiment either resulted from adding too much water or not allowing the product to remain in the Hirsch vacuum filtration for long enough to sufficiently dry.

We first, determined the percent recovery of both vanillin and unknown and then determined the melting range of both compounds. Determining the melting point range, verifies whether or not students purified the compounds properly. Pure compounds tend to have smaller and higher melting points than the original compound. Students worked individually when determining the melting range of vanillin—we were to determine the melting ranges of crude vanillin and the recrystallized vanillin made in the first lab. Moreover, students worked in pairs when determining the melting range of the unknown by using a commercial apparatus. For both solids, we watched the crystals melt. We recorded the temperature at which the solid first began melting and when the solid was completely

Discussion: As seen in the melting point determination, the average melting point range of the product was 172.2-185.3ºC. The melting points of the possible products are listed as 101ºC for o-methoxybenzoic acid, 110ºC for m- methoxybenzoic acid, and 185ºC for p- methoxybenzoic acid. As the melting point of the sample

The boiling point was 129 oC which was lower than the literature boiling point, 142 oC. Analysis by infrared spectroscopy showed the impurity (most likely CH2Cl2) containing a carbon-chlorine bond.

The purpose of this lab was to synthesize the ester isopentyl acetate via an acid catalyzed esterification (Fischer Esterification) of acetic acid with isopentyl alcohol. Emil Fischer and Arthur Speier were the pioneers of this reaction referred to as Fischer Esterification. The reaction is characterized by the combining of an alcohol and an acid (with an acid catalyst) to yield and ester plus water. In order to accomplish the reaction, the reactants were

The beaker was slowly heated on a hot plate with low stirring until most of the stilbene was dissolved. 0.4 g of pyridinium tribromide was measured and added to the beaker after 5 minutes of heating. Small amounts of ethanol were used to clean the sides of the beaker. The beaker was heated for an additional 10 minutes on low temperature. An ice bath was prepared. The beaker was removed from the hot plate and left to cool to room temperature. Once at room temperature, the beaker was placed in the ice bath for 15 minutes. The solid product was collected through vacuum filtration and the product was weighed and a melting point was taken. Waste was disposed of in the correct waste bins and lab bench was cleaned

In this experiment, methyl benzoate was synthesized from benzoic acid and methanol with acid catalyze using Fisher Esterification. First benzoic acid and methanol were mixed in 100 mL round bottom flask. We cooled the mixture in ice and poured 3 mL of conc. H2SO4 and swirled to mix compounds. Then we refluxed the mixture for 1 hour. We let the solution cool and then decanted into a separatory funnel containing 50 mL of water and rinsed the round bottom flask with 35 mL of tert-butyl methyl ether and added that to a separatory funnel. We shook and vented thoroughly and drained the aqueous layer which contained a bulk of methanol and H2SO4. We washed the solution in the separatory funnel with 25 mL of water, followed by 25 mL of sat. sodium bicarbonate

In this experiment, benzopinacol was to be synthesized through photochemical reaction and its acid-catalyzed rearrangement product benzopinacolone.