Wait a second!
More handpicked essays just for you.
More handpicked essays just for you.
Fischer esterification method
Fischer esterification method
Fischer esterification abstract
Don’t take our word for it - see why 10 million students trust us with their essay needs.
Recommended: Fischer esterification method
The experimental Fischer esterification of 8.92g of acetic acid with 5.0g of isopentyl alcohol using concentrated sulfuric acid as a catalyst yielded 4.83g (65.3% yield) of isopentyl acetate. The product being isopentyl acetate was confirmed when the boiling point during distillation had similar characteristics to that of the literature boiling points2. Physical characteristics like color and smell also concluded a match of our product with what was intended. 1H-NMR spectroscopy analysis supported this claim due to the fact that the integration values and chemical shifts were comparable to isopentyl acetate. Lastly, infrared spectroscopy (IR) showed similar key characteristics of our product’s wavelengths to that of pure isopentyl acetate5. …show more content…
The C-H (sp3) hydrogens from our product displayed at wavelength 2959 cm-1 correlates to the methyl groups located on the ends of isopentyl acetate4. A really prominent, strong peak located at 1742 cm-1 shows that a C=O ester stretch is located in the product, along with at 1244 cm-1 the spectrum shows a strong peak representing the C(=O)-O stretch that is crucial to the structure of isopentyl acetate. Shown in my IR spectrum is a weak O-H (H-bonded) peak at 3464 cm-1 which shows that I have an impurity of isopentyl alcohol in my product. Isopentyl alcohol has similar boiling points and density as my product so the impurity could have easily boiled out with the isopentyl acetate during distillation. The isopentyl alcohol was also present in my 1H-NMR spectrum backing up the impurity peak at 3464
As a final point, the unknown secondary alcohol α-methyl-2-naphthalenemethanol had the R-configuration since it reacted the fastest with S-HBTM and much slower with R-HBTM. TLC was a qualitative method and ImageJ served as a quantitative method for determining which reaction was the faster esterification. Finally, 1H NMR assisted in identifying the unknown from a finite list of possible alcohols by labeling the hydrogens to the corresponding peaks.
The goal of this experiment is to determine which products are formed from elimination reactions that occur in the dehydration of an alcohol under acidic and basic conditions. The process utilized is the acid-catalyzed dehydration of a secondary and primary alcohol, 1-butanol and 2-butanol, and the base-induced dehydrobromination of a secondary and primary bromide, 1-bromobutane and 2-bromobutane. The different products formed form each of these reactions will be analyzed using gas chromatography, which helps understand stereochemistry and regioselectivity of each product formed.
The spots moved 3.8cm, 2.3cm, 2.1cm, 1.8cm, and 2.5 cm, for the methyl benzoate, crude product, mother liquor, recrystallized product, and isomeric mixture, respectively. The Rf values were determined to be.475,.2875,.2625,.225, and.3125, for the methyl benzoate, crude product, mother liquor, recrystallized product, and isomeric mixture, respectively. Electron releasing groups (ERG) activate electrophilic substitution, and make the ortho and para positions negative, and are called ortho para directors. In these reactions, the ortho and para products will be created in a much greater abundance. Electron Withdrawing groups (EWG) make the ortho and para positions positive.
The percent yield of products that was calculated for this reaction was about 81.2%, fairly less pure than the previous product but still decently pure. A carbon NMR and H NMR were produced and used to identify the inequivalent carbons and hydrogens of the product. There were 9 constitutionally inequivalent carbons and potentially 4,5, or 6 constitutionally inequivalent hydrogens. On the H NMR there are 5 peaks, but at a closer inspection of the product, it seems there is only 4 constitutionally inequivalent hydrogens because of the symmetry held by the product and of this H’s. However, expansion of the peaks around the aromatic region on the NMR show 3 peaks, which was suppose to be only 2 peaks. In between the peaks is a peak from the solvent, xylene, that was used, which may account to for this discrepancy in the NMR. Furthermore, the product may have not been fully dissolved or was contaminated, leading to distortion (a splitting) of the peaks. The 2 peaks further down the spectrum were distinguished from two H’s, HF and HE, based off of shielding affects. The HF was closer to the O, so it experienced more of an up field shift than HE. On the C NMR, there are 9 constitutionally inequivalent carbons. A CNMR Peak Position for Typical Functional Group table was consulted to assign the carbons to their corresponding peaks. The carbonyl carbon, C1, is the farthest up field, while the carbons on the benzene ring are in the 120-140 ppm region. The sp3 hybridized carbon, C2 and C3, are the lowest on the spectrum. This reaction verifies the statement, ”Measurements have shown that while naphthalene and benzene both are considered especially stable due to their aromaticity, benzene is significantly more stable than naphthalene.” As seen in the reaction, the benzene ring is left untouched and only the naphthalene is involved in the reaction with maleic
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
2-ethyl-1,3-hexanediol. The molecular weight of this compound is 146.2g/mol. It is converted into 2-ethyl-1-hydroxyhexan-3-one. This compounds molecular weight is 144.2g/mol. This gives a theoretical yield of .63 grams. My actual yield was .42 grams. Therefore, my percent yield was 67%. This was one of my highest yields yet. I felt that this was a good yield because part of this experiment is an equilibrium reaction. Hypochlorite must be used in excess to push the reaction to the right. Also, there were better ways to do this experiment where higher yields could have been produced. For example PCC could have been used. However, because of its toxic properties, its use is restricted. The purpose of this experiment was to determine which of the 3 compounds was formed from the starting material. The third compound was the oxidation of both alcohols. This could not have been my product because of the results of my IR. I had a broad large absorption is the range of 3200 to 3500 wavenumbers. This indicates the presence of an alcohol. If my compound had been fully oxidized then there would be no such alcohol present. Also, because of my IR, I know that my compound was one of the other 2 compounds because of the strong sharp absorption at 1705 wavenumbers. This indicates the presence of a carbonyl. Also, my 2,4-DNP test was positive. Therefore I had to prove which of the two compounds my final product was. The first was the oxidation of the primary alcohol, forming an aldehyde and a secondary alcohol. This could not have been my product because the Tollen’s test. My test was negative indicating no such aldehyde. Also, the textbook states that aldehydes show 2 characteristic absorption’s in the range of 2720-2820 wavenumbers. No such absorption’s were present in my sample. Therefore my final product was the oxidation of the secondary alcohol. My final product had a primary alcohol and a secondary ketone
The IR spectrum that was obtained of the white crystals showed several functional groups present in the molecule. The spectrum shows weak sharp peak at 2865 to 2964 cm-1, which is often associated with C-H, sp3 hybridised, stretching in the molecule, peaks in this region often represent a methyl group or CH2 groups. There are also peaks at 1369 cm-1, which is associated with CH3 stretching. There is also C=O stretching at 1767 cm-1, which is a strong peak due to the large dipole created via the large difference in electronegativity of the carbon and the oxygen atom. An anhydride C-O resonates between 1000 and 1300 cm-1 it is a at least two bands. The peak is present in the 13C NMR at 1269 and 1299 cm-1 it is of medium intensity.
A weak peak was at a position between 1600-1620 cm-1 can also be seem in the IR, which was likely to be aromatic C=C functional group that was from two benzene rings attached to alkynes. On the other hand, the IR spectrum of the experimental diphenylacetylene resulted in 4 peaks. The first peak was strong and broad at the position of 3359.26 cm-1, which was most likely to be OH bond. The OH bond appeared in the spectrum because of the residue left from ethanol that was used to clean the product at the end of recrystallization process. It might also be from the water that was trapped in the crystal since the solution was put in ice bath during the recrystallization process. The second peak was weak, but sharp. It was at the position of 3062.93 cm-1, which indicated that C-H (sp2) was presence in the compound. The group was likely from the C-H bonds in the benzene ring attached to the alkyne. The remaining peaks were weak and at positions of 1637.48 and 1599.15 cm-1, respectively. This showed that the compound had aromatic C=C function groups, which was from the benzene rings. Overall, by looking at the functional groups presented in the compound, one can assume that the compound consisted of diphenylacetelene and ethanol or
ester, and we produce the most acid and alcohol. In bottle 3 we still have a good
The three butene products have been verified to elute in the following order: 1-butene, trans-2-butene, and cis-2-butene. Theory: The dehydration of 2-butanol, a secondary alcohol, progresses readily in the presence of a strong acid like concentrated sulfuric acid (H2SO4). The reaction is completed via the E1 mechanism. Initially, the hydroxyl group is a poor leaving group, but that is remedied by its protonation by the acid catalyst (H2SO4) converting it to a better leaving group, H2O. The loss of this water molecule results in a secondary carbocation intermediate that continues to form an alkene in an E1 elimination.
After performing the second TLC analysis (Figure 4), it was apparent that the product had purified because of the separation from the starting spot, unlike Figure 3. In addition, there was only spot that could be seen on the final TLC, indicating that only one isomer formed. Since (E,E) is the more stable isomer due to a less steric hindrance relative to the (E,Z) isomer, it can be inferred that (E,E) 1,4-Diphenyl-1,3-butadiene was the sole product. The proton NMR also confirmed that only (E,E) 1,4-Diphenyl-1,3-butadiene formed; based on literature values, the (E,E) isomer has peaks between 6.6-7.0 ppm for vinyl protons and 7.2-7.5 ppm for the phenyl protons. Likewise, the (E,Z) isomer has vinyl proton peaks at 6.2-6.5 ppm and 6.7-6.9 ppm in addition to the phenyl protons. The H NMR in Figure 5 shows multiplets only after 6.5 ppm, again confirming that only (E,E) 1,4-Diphenyl-1,3-butadiene formed. In addition, the coupling constant J of the (E,E) isomer is around 14-15 Hz, while for the (E,Z) isomer it is 11-12 Hz. Based on the NMR in Figure 5, the coupling constant is 15.15 Hz, complementing the production of (E,E)
The percentage yield gained was 70% from the Fischer Esterification reaction, which evaluates to be a good production of yield produced as the reaction is known to be reversible where conditions such as the concentration of the reactants, pressure and temperature could affect the extent of the reaction from performing. These white crystalline crystals were tested for impurity by conducting a melting point analysis and taking spectrospic data such as the IR spectra, HNMR and CNMR to confirm the identification of the product. These spectrospic methods and melting point analysis confirmed the white crystalline crystals were benzocaine.
Meth is all over where I live, but I have never had experience with it personally. While watching all the video clips, I now understand why so many people are addicted and what fuels their need for the drug. Unfortunately, meth grabs ahold of people and helps them ruin their lives. The lose jobs, become homeless, lose their families, get their children taken away, commit crimes, have run in with the cops, and even die. But that’s what we see on the outside, meth also ruins the users brain and thought process. How can something do so much damage to a person and their community?
Ethanol is a clear, colorless, flammable liquid. Other names that ethanol can also be known as include ethyl alcohol, ethyl hydrate, ethyl hydroxide, fermentation alcohol, methylcarbinol, and grain alcohol. The condensed structural formula for ethanol is C2H5OH, and the expanded structural formula is shown in figure 1. This chemical compound belongs to the alcohol function group therefore characterized by the hydroxyl group –OH combined with a carbon atom. Some characteristics of ethanol include a melting point at -114.1°C, boiling point at 78.5°C and a flash point at 16.6°C. Since it has a low freezing point it is used in thermometer for temperatures below -40°C, and also in antifreeze. Ethanol is the product of fermentation of carbohydrates, in the absence of air. The carbohydrates include crops like corn, wheat, grain, and barley, which makes ethanol quite economic friendly. This chemical compound is used in many processes and is found in many everyday products.
is impossible to specify a single best method to carry out a given analysis in