N-methylpiperizine (3.0 mL, 0.03 mol) by continuous stirrer at room temperature until a clear solution was obtained. The benzaldehyde (3.0 mL, 0.03 mol) was added slowly to this mixture with constant stirring. After 48 hours of continuous stirring, a white color precipitate was formed and it was washed with distilled water several times and dried in the air oven at 60 °C. The reaction scheme of MPN is shown in Figure 1.…
The results of the experiment show a percent yield of 34.34% for the first trial (Part A), and a percent yield of 84.0% for the second trial (Part B). The methods for both trials were generally the same, so the large difference is attributed to the fact that the beaker broke before the gravity-filtering step in the first trial. The beaker was attempted to be picked up by the beaker tongs, but as the hot solution was being poured into the filter, the beaker slipped out of the beaker tongs and shattered, leaving some of the product unfiltered and thus not accounted for in the final product. Although the methods were generally similar in both steps, the gravity filtration step was skipped over in the second trial, which may have accounted for the missing 16% in trial 2, but may have also accounted for the overall relatively high percent yield for this trial. Luckily, the actual melting point of benzoic acid fit within the recorded average…
The objective of this experiment was to synthesize 3-nitrochalcone from 3- nitrobenzaldehyde. This was accomplished with a Diels-Alder reaction that utilized 3-nitrobenzaldehyde and acetophenone. After the reaction was completed, purification of the product was conducted using semi-microscale recrystallization. The melting point of the product was 136-141 oC, which is in the close vicinity of the literature melting point of 146 oC. The theoretical yield of 3-nitrochalcone was 0.253g and the yield after filtration was 0.22g (percent yield of 86.9%). The percent yield after recrystallization, was 80.9%.…
Sodium Benzoate is a common food preservative used in food products such as jams and jellies, soft drinks, pickles, condiments etc and in tinned products in the market. This experiment aimed to determine whether benzoic acid is formed from it’s superior soluble form sodium benzoate in stomach acid, which is simulated by HCl (pH=2). It has been seen that at a low optimum pH, i.e. in the presence of sufficient hydrochloric acid, sufficient benzoic acid is yielded. The percentage yield is determined from the calculations of the theoretical (stoichiometric) calculations and the actual yield from the reaction. Also throughout the experiment, some basic laboratory operations such as measuring mass and volume, separating solids from liquids by vacuum filtration and drying solids are familiarized with.…
The electrophilic aromatic substitution reaction is the attack of a benzene ring on an electrophilic species resulting in the substitution of a proton with a functional group. The electrophilic aromatic substitution reaction nitration is used to nitrate methyl benzoate and acetanilide with a nitronium ion. Crystallization was used to purify the product. The melting point was used to determine its purity and the regiochemistry of the products. The methyl benzoate reaction product, methyl nitrobenzoate, was determined to be meta-substituted and the acetanilide reaction product, nitroacetanilide, was determined to be para-substituted.…
The purpose of this experiment was to synthesize the Grignard reagent, phenyl magnesium bromide, and then use the manufactured Grignard reagent to synthesize the alcohol, triphenylmethanol, by reacting with benzophenone and protonation by H3O+. The triphenylmethanol was purified by recrystallization. The melting point, Infrared Spectroscopy, 13C NMR, and 1H NMR were used to characterize and confirm the recrystallized substance was triphenylmethanol.…
The Effect of Different Concentrations of the Enzyme Catechol Oxidase on the Rate of Benzoquinone Production When Mixed with Pure Catechol…
Purpose: The purpose of this experiment was to synthesize the tertiary alcohol triphenylmethanol from a Grignard reagent, phenyl magnesium bromide. The Grignard reagent was synthesized from bromobenzene and magnesium and then reacted with benzophenone to produce triphenylmethanol. It was important that water be excluded from the reaction, in order to prevent the formation of benzene. The reaction of phenyl magnesium bromide and benzophenone was quenched with sulfuric acid, and an extraction was performed in order to separate the organic phase containing the triphenylmethanol from the aqueous phase. The triphenlmethanol was then isolated and purified by crystallization and vacuum filtration.…
Abstract: In this experiment the conversion of alcohols to alkyl halides are investigated through reflux and simple distillation. These are common procedures used to separate substances. After the reflux and distillation is complete 13C NMR and IR spectrum is used to identify the product or products for each reaction: 1a, 1b, and 2. Every individual in the group was assigned either 1a (1-propanol) or 1b (2-pentanol), and 2 (1,4-dimethyl-3-pentanol). The purpose of this experiment was to understand and become familiar with the reaction mechanisms and be able to observe and compare the product or products for each of the reactions using 13C NMR and IR. The reaction of 1-propanol (1a) with NaBr/H2SO4 was 1-bromopropane, the reaction of 2-pentanol (1b) with NaBr/H2SO4 was 2-bromopentane and the reaction of 2,4-dimethyl-3-pentanol with HCl/ZnCl2 was 2,4-dimethyl-3-chloropentane.…
The progress of the reaction was monitored in my case using two TLC plate. It first started off with the spotting of Standard benzoin and benzil which were provided in the lab and followed by the addition of the reaction mixture at once it starts changing colour/boiling, then at 10 and 20 mins into the reflux. Once all the necessary steps were spotted, the TLC plate was placed in in a beaker containing CH₂Cl₂(methylene chloride), which was used as the developing solvent in this experiment. To check to see if the desired result had been produced when the TLC plate is looked under a UV light, the reaction mixture’s spot should match the spot of benzil; your desired product. In my TLC plate, there was one more spot, which indicated that there…
Oxidation was found for primary alcohol. When 6 drops of potassium dichromate and 1 drop of concentrated sulfuric acid were added to 1-pentanol, the color of 1-pentaol turned into dark green. In second experiment, precipitation was found when 6 drops of 2,4-dinitrophenylhydrazine were added to both 5 drops of benzaldehyde and 5 drops of acetophenone. Based on these data, it is possible to find alcohol by oxidation and aldehyde by observing precipitation…
To study the affect of pH on a food preservative. Sodium benzoate changed into benzoic acid once the 3 M of HCl was added making it a pH of 2, making the solution acidic. The hydronium ion concentration was high enough that it gave a yield of benzoic acid, which, is very insoluble in water and it formed a precipitate in the solution. The end percent yield was 132.352%, this was due to a few flaws in the experiment. During the filtration process of the experiment the funnel was not working properly and not all the…
In this experiment, the production of a Grignard reagent (phenylmagnesium bromide) was performed from a bromobenzene reactant combined with magnesium and ether. Phenylmagnesium bromide was then transformed into a tertiary alcohol called triphenylmethanol, through addition of another compound called benzophenone, as well as additional ether. The end product of triphenylmethanol was analyzed via NMR and IR. Figure 1: Preparation of the Grignard agent by combining bromobenzene with magnesium and ether to produce phenylmagnesium bromide. Figure 2: Production of triphenylmethanol by combining benzophenone and the Grignard reagent.…
Abstract The structure of a major component of star anise oil was derived by analyzing its IR spectroscopy melting point of after oxidation and purification. From the evidence obtained, it was concluded that the exact structured should be p-methoxybenzoic acid. Introduction The purpose of this experiment is to determine the structure of the major component of star anise oil. It is already known that this component has a molecular formula C10H12O. This molecular formula equates to an IHD of 5. It is evident, by calculating the IHD, that this compound contains a benzene ring. By heating anisene with hydroiodic acid the following reaction occurs: [rxn 1] The resultant of a phenol indicates that anisene is, in fact, an aryl methyl ether with the formula C9H9OCH3. Since all these facts have been established about the structure of anisene, what is to be determined from this experiment is the structure of the unsaturated side chain and its location. In order to do this, anisene will first be oxidized with KMNO4 so as to then identify the oxidation product and establish the positioning of the side chain. The reaction is as follows: Finally purification of the structure of the unknown oxidized component, its structure shall be determined by obtaining the melting point and by means of IR spectroscopy of the original substance. Experimental The experiment was carried out following the procedure described in Experiment 24 of the assigned lab book (Lehman 188-195) with some deviation: When it was time to use the condenser the first time around, the tubes for the water to circulate were not attached, causing the solvent to evaporate. Consequently, more solvent had to be added and the experiment continued normally. Calculations The weight of the total final product is equal to the weight of the watch glass and the final product minus the weight of the watch glass. Wt of Final product = (wt of watch glass and product)-(wt…
Assessment of sample purity for a known substance. By comparing observed range for an actual sample to the known range for a pure sample, I can tell whether my actual sample is pure or contaminated (the range is depressed and broadened). So, In part A, melting point of benzoic acid was observed in range 122 to 125 ¨¬C. By comparing melting point of benzoic acid (121 ¨¬C) with result from part A, the result is little higher than the pure melting point. So I can tell it is little contaminated.…