For this lab we performed an electrophilic aromatic substitution through the nitration of methyl benzoate. Aromatic compounds can and do react with electrophiles under vigorous reaction conditions and in a presence of a catalyst. The stability of aromatic compounds is a result of resonance. Aromatic compounds only react with powerful electrophilic reagents and elevated temperatures because aromatic electrons are less reactive in addition reactions as formation of a carbocation intermediate entails loss of resonance stabilization. The nitration of methyl benzoate to synthesize methyl m-nitrobenzoate is an example of an electrophilic aromatic substitution because a nitro group is substituted for a proton on the aromatic ring. For this experiment, the electrophilic reagent is nitronium ion, it is formed by sulfuric acid on nitric acid. Furthermore, the less water present or the more sulfuric acid present, the more nitronium ion formed. The nitronium ion highly are highly electrophilic and can disrupt ring resonance so it can add to an aromatic ring. Moreover, the intermediate formed is stabilized by resonance and loss of proton. The presence of a carbomethoxy …show more content…
Additionally, there were tiny white properties in the mixture. For this lab the experimental yield for the final product is 3.65g, and the melting point of the product came to be 71C. The experimental yield of the product was very close to the theoretical yield, 4.45g, and using the actual and theoretical yield the percent yield was calculated to be 82%. The literature melting point of the final product is 78C, which is very close to the experimental melting point. The experimental melting point was a less than the literature melting point because there were less impurities, the experimental final product was probably purer as a result of the vacuum filtration conducted using methanol and distilled
Many sources of error were responsible for recovering a small amount of product. Introduction: The carbon-carbon bond formation is an important tool in organic chemistry to construct the simple as well as an organic compound. There are several
Grignard is a reaction that is crucial to forming the new carbon-carbon bond. This is a two-part lab that teaches new techniques; the purpose of this lab is to introduce realistic organic synthesis and apply acid workup to produce triphenylmethanol. A Grignard reaction is characterized by the addition of a magnesium halide (an organomagnesium halide) to an aldehyde or a ketone in order to form a secondary or tertiary alcohol. These reactions are helpful because they serve as a crucial tool in performing important carbon-carbon bond-forming reactions (Arizona State University, 2018). This experiment aimed to observe the mechanisms of a Grignard reply to synthesize triphenylmethanol from benzophenone using phenylmagnesium bromide as the Grignard reagent.
The most common atom to be replaced is a hydrogen atom, but occasionally other atoms may also be swapped out by an electrophile. Within this reaction, the substituents connected to the benzene ring demonstrate directing behavior that can affect the formation of the product. These substituents can either act as an ortho/para or meta director, which ultimately determine where the electrophile is added onto the ring. Figure 2. Bromine Production via Potassium Bromate and Hydrobromic Acid.1
The purpose of this experiment was to learn about the electrophilic aromatic substitution reactions that take place on benzene, and how the presence of substituents in the ring affect the orientation of the incoming electrophile. Using acetanilide, as the starting material, glacial acetic acid, sulfuric acid, and nitric acid were mixed and stirred to produce p-nitroacetanilide. In a 125 mL Erlenmeyer flask, 3.305 g of acetanilide were allowed to mix with 5.0 mL of glacial acetic acid. This mixture was warmed in a hot plate with constantly stirring at a lukewarm temperature so as to avoid excess heating. If this happens, the mixture boils and it would be necessary to start the experiment all over again.
Lecturer Date Introduction Theoretical Background Procedure The procedure was segmented into two categories, the reaction set up and the crude product isolation. Reaction set up The magnetic stirrer was prepared through placing it in the fume cupboard. 1 mmol of L-Phenylalanine was placed and weighed in a 5 mL conical vial.
The reaction to synthesize benzocaine was known as a Fisher esterification reaction. The Fisher esterification was reaction between alcohol and carboxylic acid in the presence of acid. The reaction was used to form an ester. In the experiment, sulfuric acid acted as a catalyst and necessary for this reaction to occur. There was a change between the –OH group of carboxylic acid to an –OCH2CH3 group in the reaction.
Chem 51 LB Experiment 3 Report Scaffold: Bromination of Trans-Cinnamic Acid 1. The goal of this experiment was to perform a halogenation reaction through the addition of two bromides from pyridinium tribromide. This was accomplished by reacting trans-cinnamic acid with pyridinium tribromide. After the reaction took place, melting point analysis was conducted to find out the stereochemistry of the product, which could either be syn-addition, anti-addition, or syn + anti-addition. 2.
As seen in table 1, the theoretical yield was .712 g of C_17 H_19 NO_3. The % yield of this experiment was 7.51 % of C_17 H_19 NO_3. . This low yield can be explained from a poor recrystallization technique combined with potential contamination. Throughout the experiment, the mixture changed color from green, orange, to yellowish lime, and eventually clear.
Next, the oxygen is protonated from the 3-nitrobenzaldehyde, which is then followed by an elimination reaction where this acts as a leaving group. The product is the trans-alkene present in the product. After the reaction was completed, purification of the product was conducted using semi-microscale recrystallization.
Firstly, because the NaHCO3 compound was not stored in a sealed container, therefore dust particles could have changed the results, and making the product impure. Also, there are uncertainties associated with the instruments used in this experiment. This, if the products were measured slightly more than should be, this could have affected the concentrations of the solutions, and therefore causing a larger
Experiment 2 Report Scaffold (Substitution Reactions, Purification, and Identification) Purpose/Introduction 1. A Sn2 reaction was conducted; this involved benzyl bromide, sodium hydroxide, an unknown compound and ethanol through reflux technique, mel-temp recordings, recrystallization, and analysis of TLC plates. 2. There was one unknown compound in the reaction that was later discovered after a series of techniques described above.
It is understood the mechanism is acid-catalyzed where protons coordinate with the carbonyl oxygen to make the carbonyl carbon more electropositive for nucleophilic attack (Scheme 1). In the experimental procedure all reactants were added together, this is inefficient as the protons can coordinate with either trans-cinnamic acid or methanol. Coordination with methanol is unnecessary as it reduces its nucleophilicity and makes less protons available to coordinate with the carboxylic acid. To improve
In other lab procedures, benzoic acid is sometimes substituted for anisole in the Friedel-Craft acylation. However, the reason benzoic acid
Two varieties of pomegranates named Rabab and Hasibi which are harvesting in Yazd (Iran), have been used. Fruits were peeled and dried up under sunlight. They were washed with sterile distilled water. The dried rinds were grinded into a fine powder by Mixing grinder.
Abstract The unknown concentration of benzoic acid used when titrated with standardized 0.1031M NaOH and the solubility was calculated at two different temperatures (20◦C and 30◦C). With the aid of the Van’t Hoff equation, the enthalpy of solution of benzoic acid at those temperatures was determined as 10.82 KJ. This compares well with the value of 10.27KJ found in the literature.