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Essays 2 pages, words The procedure stated in Chem experiment 6 Williamson Ether Synthesis of Phenacetin laboratory manual was followed without any major changes. It extracts a set of general product features, finds product specific features and feature attributes and is thus Combined with provided heuristic rules, the model yields better results than the general naive bayes classifier.
Physical appearance for products: On addition of acetaminophen to sodium ethoxide there was a brown coloured solution formed. Amide synthesis of phenacetin crude product obtained was observed to have a beige appearance, and the crystals formed where powdery in texture.
On the other hand, the pure recrystallized product gave a shiny white colour appearance, with its crystals being needle like in texture. TLC plate with acetaminophen and phenacetin standard, experimental phenacetin spots. Table2- Qualitative analysis using Chromatography. The Rf values of the standards and re-crystallized sample.
The TLC results seen in table 2 above were used to determine the true identity of the experimental product. The standard acetaminophen sample spot had a retention factor value of 0.
And the spot done for the crude and re-crystallized product gave a retention factor value of 0. The Mel Temp temperature had a range of C and the standard documented melting point for Phenacetin is C. Sodium ethoxide NaOEt was used to react with acetaminophen.
K2CO3 is anhydrous, and the Williamson ether synthesis majorly involves the removal of a proton from an alcohol using an SN2 nucleophilic reaction. When potassium carbonate is present in a solution with acetaminophen it generates the conjugate base of acetaminophen which is powerful enough to pull apart iodoethane.
Iodide is left in solution while the CH3CH2 is bonded to acetaminophen and phenacetin is the product. However, Williamson ether synthesis process requires a strong base such as sodium hydride or sodium metal.
Recrystallization requires careful techniques which if not followed properly could lead to loss of recrystallized product. Some loss, resulting from transferring solids from one container to another and leaving a little material behind, cannot be avoided.
But it can be ignored by improving the techniques employed in transferring the product. Also, because of the solubility of the solid in the recrystallization solvent, even at low temperatures, any unnecessary prolonged contact with recrystallization solvent, especially if the solvent is not ice-cold will result in loss of product.
These include producing product within quality standards at least cost, employing capital budgeting technique in Since operations deals with how For that reason, the following problems commonly occur: If the solid is dissolved below the boiling point of the solution, too much solvent will be needed, resulting in a poor yield.
In order to obtain optimal results, a minimum of near-boiling solvent should be used for the recrystallization, and a minimum of ice cold solvent should be used for the rinse. The recrystallized product was considered to be pure due to the fact that, when ran through the TLC plate, an Rf value of 0.
Was obtained which is similar to the Rf value of the standard phenacetin 0. Acetaminophen produced Rf value of 0.
Acetaminophen consists of hydroxyl group which is more polar than phenacetin consisting of ethoxide group. This causes acetaminophen to travel much slowly up the column; phenacetin is more soluble and hence travels faster up the column less affinity to stationary phase in the mobile phase.
When the Mel-Temp apparatus was used to observe the melting point of the recrystallized product, it was discovered that the melting point of the experimental phenacetin oC was just a fraction off the literature melting point of phenacetin oCthe mel range of the experimental product is narrow same as the literature melting point thus revealing the purity and the identification of the phenacetin product attained in this experiment.
Phenacetin can also be made by the Schotten-Baumann reaction which is an organic reaction used to convert an acyl halide or anhydride to an amide if reacted with an amine and base. The acid particles move randomly and as the concentration of the However i decided that i would measure the products forming which would be the volume of gas given off In this reaction there is use of added base to drive the equilibrium in the formation of amides from amines and acid chlorides.
The acylation of amines with carboxylic acid chlorides leads to the production of one equivalent acid, which will form a salt with unreacted amine and diminish the yield.
The addition of an additional equivalent of base to neutralise this acid is a way to optimise the conditions. Normally, aqueous base is slowly added to the reaction mixture.O CHEM LAB QUIZ STUDY. PLAY. What is an active constituent of APC tablets?
What functions as a nucleophile in its subsequent reaction with bromoethane to yield phenacetin? What is used to increase the reactivity in amide synthesis? acetic anhydride protonation. What acts as the nucleophile in amide synthesis?
Mar 03, · Best Answer: In the amide formation reaction for the synthesis of phenacetin from para-ethoxyaniline, control of the acidity of the reaction mixture is important in maximizing the product yield.
Protonation activates the acetic anhydride towards nucleophilic attack, Status: Resolved. Nonplanar, electronically destabilized amides are powerful intermediates in organic synthesis.
A highly selective method for transamidation of common secondary amides under mild, metal-free conditions relies on transient N -selective functionalization to weaken amidic resonance. Mar 03, · Best Answer: In the amide formation reaction for the synthesis of phenacetin from para-ethoxyaniline, control of the acidity of the reaction mixture is important in maximizing the product yield.
Protonation activates the acetic anhydride towards nucleophilic attack, however, if the pH of the solution is too low, the starting Status: Resolved. The synthesis of Acetaminophen is based on the amine group of p-aminophenol being acetylated by acetic anhydride to form an amide functional group.
Acetaminophen is isolated as a crude solid which is then recrystallized to purify the product. The synthesis of paracetamol can be broken down into 3 parts: Part 1 – mix the reactants together to form paracetamol.
Part 2 – isolate crude paracetamol from .