Introduction:
Alkyl halides are compounds that are considered as good “leaving groups” when these good leaving groups are replaced by another atom that is called “substitution”. When a nucleophile substitution occurs, this is an act of replacement of the leaving group [1]. When substitute happens nucleophile reacts, that is and electron pair donor, while the reaction releases this make electrophile as the receptor [2]. These alkyl halides will be prepare from alcohol while reacting with halides, this mechanism support the substitution of alcohols [3]. A “First order of Nucleophilic substitution” of SN1, a weak nucleophile, which is unimolecular, a reaction that occurs step by step. The solvent that is favored by SN1 is polar protic [4]. SN2,
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After 5 minutes yellow in color formed and precipitation did not form. Other steps in this experiment did not happen for test tube 1, for example, after the first 5 minutes, and no changes occurred test tube 1 needed to go into the ice bath to confirm “no reaction”. Therefore test tube 1 data were inconclusive. Test tube 2 contained the synthesized product along with 1 mL of 1% ethanolic silver nitrate, precipitation came rapidly fast for test tube 2. The color was clear and instantly cloudy and white precipitate appeared. Test tube 3 contained 0.2 mL of 1-chlorobutane and the tert-butyl chloride, when shaking the test with the product closed in by the cork the test tube products went from clear to dull yellow color. No precipitation was formed after 5 minutes; therefore, the test tube was placed in a 53 °C of water for an additional 5 minutes. Precipitation appear on the side of the test tube. Test tube 4 contained 0.2 mL of 1-chlorobutane and the tert-butyl chloride, no changes and no precipitation were form. Same as for test tube 1, test tube 4 did not undergo the ice bath after the first 5 minutes, the ice bath is used to confirm if reaction is possible. Test tube 4 data was also …show more content…
In the reaction involving both tert-butyl chloride and tert-butyl alcohol there were correctly synthesized. In SN1 as I mention in the introduction, is a weak nucleophile, unimolecular, and polar protic that most like occur in those leaving groups that is tertiary. In SN2, is a strong nucleophile, bimolecular and is polar aprotic and reaction for this leaving group is primary. In the last part of the experiment SN1 and SN2 reactions was analyzed when 18% of solution of sodium iodide and silver nitrate was mixed in the respective test tubes although test 1 form a yellow color; however, the lack of precipitation indicates this wouldn’t be consider a reaction so these data are inconclusive. Test tube 2 contained the synthesized product along with 1 mL of 1% ethanolic silver nitrate, precipitation came rapidly fast, and this came to be the most successful testing. Test tube 3 contained 0.2 mL of 1-chlorobutane and the tert-butyl chloride and had the positive reactions that was aimed for from the introduction were the ones that came out to be the most successful
The competing enantioselective conversion method uses each enantiomer of a kinetic resolution reagent, in this case R-HBTM and S-HBTM, in separate and parallel reactions, where the stereochemistry of the secondary alcohol is determined by the rate of the reactions. When using the CEC method, the enantiomer of the secondary alcohol will react with one enantiomer of the HBTM acyl-transfer catalyst faster than with the other HBTM enantiomer. The mnemonic that identifies the absolute configuration of the secondary alcohol is as follows: if the reaction is faster with the S-HBTM, then the secondary alcohol has the R-configuration. In contrast, if the reaction is faster with the R-HBTM, then the secondary alcohol has the S-configuration. Thin layer chromatography will be used to discover which enantiomer of HBTM reacts faster with the unknown secondary alcohol. The fast reaction corresponds to a higher Rf spot (the ester) with a greater density and a slower reaction corresponds to a lower Rf spot with high de...
Reacting 1-butanol produced 2-trans-butene as the major product. 1-butanol produces three different products instead of the predicted one because of carbocation rearrangement. Because of the presence of a strong acid this reaction will undergo E1 Saytzeff, which produces the more substituted
Then the reaction tube was capped but not tightly. The tube then was placed in a sand bath reflux to heat it until a brown color was formed. Then the tube was taken out of the sand bath and allowed to cool to room temperature. Then the tube was shaken until a formation of a white solid at the bottom of the tube. After formation of the white solid, diphenyl ether (2 mL) was added to the solution and heated until the white solid was completely dissolved in the solution. After heating, the tube was cooled to room temperature. Then toluene (2 mL) was added to the solution. The tube was then placed in an ice bath. Then the solution was filtered via vacuum filtration, and there was a formation of a white solid. Then the product was dried and weighed. The Final product was hexaphenylbenzene (0.094 g, 0.176 mmol,
The purpose of this lab was to perform an electro-philic aromatic substitution and determine the identity of the major product. TLC was used to detect unre-acted starting material or isomeric products present in the reaction mixture.
The goal of this two week lab was to examine the stereochemistry of the oxidation-reduction interconversion of 4-tert-butylcyclohexanol and 4-tert-butylcyclohexanone. The purpose of first week was to explore the oxidation of an alcohol to a ketone and see how the reduction of the ketone will affect the stereoselectivity. The purpose of first week is to oxidize the alcohol, 4-tert-butylcyclohexanol, to ketone just so that it can be reduced back into the alcohol to see how OH will react. The purpose of second week was to reduce 4-tert-butylcyclohexanol from first week and determine the effect of the product's diastereoselectivity by performing reduction procedures using sodium borohydride The chemicals for this lab are sodium hypochlorite, 4-tert-butylcyclohexanone
Alcohol, which is the nucleophile, attacks the acid, H2SO4, which is the catalyst, forming oxonium. However, the oxonium leaves due to the positive charge on oxygen, which makes it unstable. A stable secondary carbocation is formed. The electrons from the conjugate base attack the proton, henceforth, forming an alkene. Through this attack, the regeneration of the catalyst is formed with the product, 4-methylcyclohexene, before it oxidizes with KMnO4. In simpler terms, protonation of oxygen and the elimination of H+ with formation of alkene occurs.
Discussion and Conclusions: Interpreting these results have concluded that relative reactivity of these three anilines in order of most reactive to least reactive go; Aniline > Anisole > Acetanilide. Aniline, has an NH2 , the most active substituent , and adds to any ortho/para position available on the ring. This data is confirmed with the product obtained, (2,4,6 tribromoaniline, mp of 108-110 C). As for anisole, it has a strongly activating group attached, OMe an alkoxy group, and it added in two of the three available spots, both ortho. The results conclude: (2,4-Dibromoanisol mp 55-58 C ). Acetanilide has a strong activating group attached, acylamino group, but this group is large and the ortho positions are somewhat hindered so the majority of the product obtained added at the para position, results conclude: (p-bromoacetanilide mp 160-165 C). Since all the substituents attached to the aromatic rings were activators the only products able to be obtained were ortho/para products.
Triphenylmethyl Bromide. A 400 mL beaker was filled with hot water from the tap. Acetic acid (4 mL) and solid triphenylmethanol (0.199 g, 0.764 mmol) were added to a reaction tube, with 33% hydrobromic acid solution (0.6 mL) being added dropwise via syringe. The compound in the tube then took on a light yellow color. The tube was then placed in the beaker and heated for 5 minutes. After the allotted time, the tube was removed from the hot water bath and allowed to cool to room temperature. In the meantime, an ice bath was made utilizing the 600 mL plastic beaker, which the tube was then placed in for 10 minutes. The compound was then vacuum filtered with the crystals rinsed with water and a small amount of hexane. The crude product was then weighed and recrystallized with hexane to form fine white crystals, which was triphenylmethyl bromide (0.105 g, 0.325 mmol, 42.5%). A Beilstein test was conducted, and the crystals produced a green to greenish-blue flame.
In this lab 4-tert-butylcyclohexanone is reduced by sodium borohydride (NaBH4) to produce the cis and trans isomers of 4-tert-butylcyclohexanol. Since the starting material is a ketone, NaBH4 is strong enough to perform a reduction and lithium aluminum hydride is not needed. NaBH4 can attack the carbonyl group at an equatorial (cis) or axial (trans) position, making this reaction stereoselective. After the ketone is reduced by the metal-hydride, hydrochloric acid adds a proton to the negatively charged oxygen to make a hydroxyl group. The trans isomer is more abundant than the cis based on the results found in the experiment and the fact that the trans isomer is more stable; due to having the largest functional groups in equatorial positions.
The reaction of (-)-α-phellandrene, 1, and maleic anhydride, 2, gave a Diels-Alder adduct, 4,7-ethanoisobenzofuran-1,3-dione, 3a,4,7,7a-tetrahydro-5-methyl-8-(1-methylethyl), 3, this reaction gave white crystals in a yield of 2.64 g (37.56%). Both hydrogen and carbon NMR as well as NOESY, COSY and HSQC spectrum were used to prove that 3 had formed. These spectroscopic techniques also aided in the identification of whether the process was attack via the top of bottom face, as well as if this reaction was via the endo or exo process. These possible attacks give rise to four possible products, however, in reality due to steric interactions and electronics only one product is formed.
This experiment was divided into two main steps. The first step was the addition of bromine to trans-stilbene. Trans-stilbene was weighted out 2.00g, 0.0111mol and mixed with 40ml of glacial acetic acid in 100ml Erlenmeyer flask on a hot bath. Pyridinium hydrobromide perbromide of 4.00g, 0.0125mol was added carefully into the flask.
The product was recrystallized to purify it and the unknown filtrate and nucleophile was determined by taking the melting points and performing TLC. Nucleophilic substitution reactions have a nucleophile (electron pair donor) and an sp3 electrophile (electron pair acceptor) with an attached leaving group. This experiment was a Williamson ether synthesis usually SN2, with an alkoxide and an alkyl halide. Conditions are favored with a strong nucleophile, good leaving group, and a polar aprotic solvent.
The reaction performed in this experiment was bromination of an alkene, using trans-Cinnamic acid, Pyridinium Tribromide, and Glacial Acetic Acid.
The most classic and standard procedure for producing esters is the Fisher-esterification reaction. Discovered in 1895 by German chemists Emil Fischer and Arthur Speier 4, this reaction involves refluxing a carboxylic acid and an alcohol in the presence of an acid catalyst. In order to drive the equilibrium towards the products, the water from the dehydration process must be removed and there must be an excess amount of alcohol. A vast range of carboxylic acids may be used for this reaction however the type of alcohols are limited. Primary and secondary alcohols are most frequently used in esterification reactions, tertiary alcohols are steric ally hindered usually resulting in poor yields5 and tend to undergo elimination reactions instead. In this rea...
SN2 reactions are described as bimolecular nucleophilic substitution reactions that occur in one concerted step without the formation of a carbocation intermediate. These reactions are performed most effectively in polar aprotic solvents such as acetone. The steric hindrance presented in the substrate is considered the most important factor due to the fact that the more steric hindrance there is around the halide, the harder it is for it to leave. The collected data for the SN2 reactions support this logic by showing that primary halides on substrates 4, 6, and 7 occurred within the first 5 minutes of the reaction. Substrates 6 and 7 were acted on immediately because 6 is allylic and 7 is benzylic, which creates an over lap of the pi bonds