Secretary of Commerce on behalf of the United States of America. These results indicated that we had a pure product. This peak would have also been found in the spectrum for p-aminobenzoic, so this is not a good indication of a successful synthesis of benzocaine. The impurity will stay in the solvent, giving a pure compound. Select a region with data to zoom.
In between each of these colors we observe intermediate colors like magenta, teal, orange and pink. There was a calculated crude percent yield of 92%, a percent recovery from recrystallization of 22%, leading to an actual percent yield of 19%. Harvey Whitney Books Company, 2012. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. An interpreter is a computer program that executes the instructions written in a high level programming language. Also, as the dots were fairly distinct, it seems to lead to the conclusion that there is no evidence that there is presence of the starting material in the reaction product. These two protons are shifted so fardown due to the deshielding caused by the ester and the amine substituents.
There is a moderate peak for p-aminobenzoic acid at 2982. Another group indicating the successful synthesis of benzocaine is O-C ester bond at 1116 cm -1. Secretary of Commerce on behalf of the United States of America. A lone pair on the ethanol oxygen will attack the carbonyl carbon, this will then form an intermediate tetrahedral compound. Furthermore, quantification of analytes is possible in the presence of unknown interferents if pure analyte standards are available. Secretary of Commerce on behalf of the United States of America. N will have a + charge due to the addition of the hydrogen, and Cl will have a - charge because of deprotoniztion.
© 2018 by the U. The product appeared to be a white crystalline solid, tabular, semi-transparent with moderate reflectivity, ~5mm in width. Starting with p-aminobenzoic acid and sulfuric acid as the catalyst, the carboxylic acid functional group on the p-aminobenzoic acid will protonated by the sulfuric acid. This shows that recrystallization is effective at removing impurities. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Synthesis of Benzocaine Essay A. In particular, theFischer Esterification reaction was used in this lab to turn a carboxylic acid into an esterbenzocaine.
Benzocaine exhibits two main components common to the anaesthetic family: 1 an aromatic system usually having directly attached an ester and 2 a one to four unit hydrocarbon chain. It was within the narrow range of the known melting point for our product, which indicates purity of our substance. Benzoic acid is the stronger acid compared to ethanoic acid. Because these hydrogen atoms are the farthest from the electronwithdrawing oxygen atoms, it makes sense that they would have the lowest chemical shift, andsuffer the most shielding of all the protons of the molecule. Benzocaine is an ester that has been used in the medical industry as a local anasethetic fordecades.
Some contribute the use of benzocaine as an anesthetic to cause methemoglobinemia,which is a negative disorder that is caused by high levels of methemglobin in the blood. Other ions of benzocaine were present in the mass spectrum, including a peakat 150. This missing group give indication that the starting p-aminobenzoic acid is not present. Use this link for bookmarking this species for future reference. The biphenyl can be extracted by distillation, as ether is quitevolatile and will evaporate easily B. Theshort range and accuracy implies a successful synthesis. By using the concept of differing solubility in differing solvents recrystallization is able to be used so only one of the compounds, benzocaine in this experiment, recrystallizes.
Benzoic acid is not a polar molecule because the overall molecule lacks a dipole resulting a slightly positive side and a slightly negative side. This presence of benzocaine shows that from the reaction of p-aminobenzoic acid and 100% ethanol, there is a high efficiency of esterification reactions in the presence of a catalyst. This accuracy in melting point indicates a pure product. The reaction mixture was then cooled to roomtemperature. A Hirsch funnel was then used in vacuum filtration to isolate theproduct. The melting point we received was within the range of the known melting point.
An air condenserwas used to reflux the reaction for one hour. The next peak, a quartet, at4. With fore-said spectrum, visible lights highest frequency color appears to us as purple. References Go To: , , Data compilation by the U. A peak appeared at 18. George; Life Science First Year Student Answer.
The upper organic layerwill contain biphenyl dissolved in ether, and the lower aqueouslayer will contain the water soluble salt of benzoic acid andwater. The mixture was thencooled with ice and concentrated sulfuric acid 0. The include common identification numbers, the , U. Results and Discussion: The synthesis of benzocaine utilized Fisher esterification of a carboxylic acid, p-aminobenzoic, and an alcohol, 100% ethanol, with a catalyst, sulfuric acid. Furthermore, the melting point range achieved 88-89ï¿½C concurred well with the literature value of 89ï¿½C, confirming the purity of the obtained sample.
Filter the ether solution and then remove the ether, the solvent, in order to obtain the pure benzoin. Another good indication of the purification of benzocaine is the lack of a peak at 11-12 ppm, which would have appeared if p-aminobenzoic acid was present. The next peak has a splitting pattern of a singlet at 5. Pharmacology, and Abuse of Cocaine, Amphetamines, Ecstasy, andRelated Designer Drugs. The theoretical yield of benzocaine was 144. It begins with the carbonyl oxygen of a carboxylic acidbeing protonated by the catalytic sulfuric acid. We can see the starching frequency for P-amino benzoic acid but it we cannot see the absorption in case of ethyl -P-amino benzoate.