Organic 2 Lab Report

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%

2. The TLC results showed two different spots that traveled different distances on the TLC plate, one for ethyl vanillin and one for ethyl vanillin alcohol which proves there is no evidence of the starting material in our final product. The product (ethyl vanillin alcohol) was more polar and interacted more with the solvent than our starting material (ethyl vanillin). This increase in polarity is due to the extra alcohol group in the ethyl vanillin alcohol and the smaller Rf value also indicates it is more polar and pure than the ethyl vanillin.

The unknown sample was then heated in boiling water in step 5. The reason for heating the

4- chlorobenzoic acid which was the aqueous layer has a theoretical melting point of 240-243°C, the organic layer, 4-chlorobenzyl alcohol has a theoretical melting point of 68-71°C. During our experiment we were unable to collect any data for the organic

Fragment 7 is shown in the structure. Electron density map suggested two bulk electro-rich group present in the fragment, which corresponds to the two ring structure on 7. The heterocyclic ring has high e-density and forms a hydrophobic interaction with Leu144 residue. The e-rich NH2 group on this ring

We can know from the unknown melting point table that this acid is o-Toluic because o-Toluic melting point is (103-105) °C. This was coming from NaOH extraction, which we added 10% HCl to make it acidic and recovered the acid. The crystalized form of NaOH was still wet when doing the measurement, so that make the temperature a little bit higher than theoretical melting point. Even that, it was left for a week to dry but the recovered acid was accumulated over each other, and can feel it was still wet when taking the acid in pipette to measure the melting

In the first part of the experiment (identifying the chemical makeup of the unknown compound

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

Identifying this organic acid was an extensive task that involved several different experiments. Firstly, the melting point had to be determined. Since melting point can be determined to an almost exact degree, finding a close melting point of the specific unknown can accurately point to the identification of the acid. In this case the best melting point

Both the 1H NMR and GC/MS spectra support the conclusion that the products are propyl xylene and iso-propyl xylene in a 7:3 ratio. Being that iso-propyl xylene and propyl xylene share a similar structure, many of their peaks are overlapping. Peaks B, D, and C are all hydrogens attached directly to the aromatic, and are found at approximately 7.1ppm. These peaks slightly differ in their multiplicity, with B being and singlet, and D and C appearing as doublets. The structures also share peaks for the hydrogens attached to the methyl substituents, which are shown at 2.40ppm as a large singlet. The peaks begin to somewhat deviate when looking at the propyl group. It was primarily peak G, that allowed for the differentiation between the propyl and iso-propyl

I can narrow down my unknown substance to either Ethanol or 2-proponal. Ethanol’s density is only 0.001g/mL higher than my own measurements, but its boiling point is 8.4̊C lower than GNR’s. Whereas 2-proponal’s density is off by 0.003g/mL and its boiling point is only off by 4.5̊C. If I were to make an educated guess I would lean more towards Ethanol. Both the precision and accuracy of my data was far greater in density than in boiling point and Ethanol’s density is closer to GNR’s than any other substance.

Observed the following structure of ethyl methyl ketone( 2-butanone) carefully and answer the following questions

I am proposing that the identity of the pure compound used for this experiment is Ethyl-4-Nitrobenzoate. I am about 90% sure about this identification being the correct one. Ethyl-4-Nitrobenzoate has been recorded by multiple chemists to have a melting point between 57o and 58o. For our experiment, the pure compound began melting at 55.3o and did not stop melting until the thermometer reached 57.4o. When the pure sample was heated at a rapid pace, the melting point was between 50.3o and 57.6o. Even when the pure sample was heated at a slower pace, the melting point was still around 57o. While I may be 90% sure that my identification for this pure compound is correct, I am still 10% unsure if this is the correct and accurate identification.

The results from the NMR of 1-propanol showed 3 different prominent peaks with the peak at 2.2 cm-1 being the acetone. Because 1-bromopropane has three non-equivalent hydrogens it was found to represent this set of NMR data. The other product, 2-bromopropane only had 2 different types of hydrogens and would have only had 2 peaks. Further analysis of the structure of 1-bromopropane showed that the hydrogens closest the bromine group were an indication of peak A in the graph. Because of the electronegativity of the bromine, this peak was located further downfield. There were 2 neighboring hydrogens so using the n+1 rule gave the 3 peaks. Going down peak B showed the next carbon which had 5 neighboring hydrogens thus giving 6 peaks. Finally, the carbon furthest away from the bromine was found at peak C. It had 2 neighboring hydrogens and provided 3 peaks.

By Using specific methods of compounds detection, we can match an unknown compound with a known compound because similar compounds will display similar characteristics. In this experiment, identifications of the unknown ketone was accomplished using thin layer chromatography, melting point, and NMR spectrometry. Thin layer chromatography is very quick but sensitive way of determining the components of a mixture or a specific compound from a list of knowns. This method is the one which was utilized in the