The purpose of this experimentation is to be able to separate cyclohexane and toluene (two miscible liquids), using simple and fractional distillation. In addition, analyze the efficiencies of a simple and fractional distillation. A brief overview of this experiment is placing two liquid mixtures into a round bottom flask, fitted with a distilling head, condenser and thermometer, and heating up the solution with a hot plate. Because of the large surface area of the heating flask, it permits transfer of sufficient thermal energy to distill components of a mixture. In typical boiling conditions, as the mixture is heated equilibrium develops amongst the vapor and liquid phase, separating out in the vapor phase the lower boiling component. Too
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.
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.
This week’s lab was the third and final step in a multi-step synthesis reaction. The starting material of this week was benzil and 1,3- diphenylacetone was added along with a strong base, KOH, to form the product tetraphenylcyclopentadienone. The product was confirmed to be tetraphenylcyclopentadienone based of the color of the product, the IR spectrum, and the mechanism of the reaction. The product of the reaction was a dark purple/black color, which corresponds to literature colors of tetraphenylcyclopentadienone. The tetraphenylcyclopentadienone product was a deep purple/black because of its absorption of all light wavelengths. The conjugated aromatic rings in the product create a delocalized pi electron system and the electrons are excited
In order to separate the mixture of fluorene, o-toluic acid, and 1, 4-dibromobenzene, the previously learned techniques of extraction and crystallization are needed to perform the experiment. First, 10.0 mL of diethyl ether would be added to the mixture in a centrifuge tube (1) and shaken until the mixture completely dissolved (2). Diethyl ether is the best solvent for dissolving the mixture, because though it is a polar molecule, its ethyl groups make it a nonpolar solvent. The compounds, fluorene and 1, 4-dibromobenzene, are also nonpolar; therefore, it would be easier for it to be dissolved in this organic solvent.
barbier reaction: In a 50 mL round bottom flask that had a reflux condenser attachment, saturated ammonium chloride (5 mL), THF (1 mL), zinc powder (0.4 g), benzaldehyde (0.500 mL, 0.5225 g, 4.92 mmol), and allyl bromide (0.470 mL, 0.6533 g, 5.40 mmol) were charged with stir bar and stirred at room temperature for 45 minutes. Diethyl ether (10 mL) was added to the reaction mixture and stirred. The mixture was gravity filtered into a beaker that was topped with a watchglass. The filtrate was transferred to a separatory funnel and the organic layer was extracted with deionized water (10 mL) and diethyl ether (15 mL). The organic layer was placed into an Erlenmeyer flask and the aqueous layer was placed into a beaker, which was extracted with
Benzyl bromide, an unknown nucleophile and sodium hydroxide was synthesized to form a benzyl ether product. This product was purified and analyzed to find the unknown in the compound.
We successfully achieved our goal of synthesizing benzhydrol, but we did not successfully reach the goals of the completion of the synthesis or purification of benzhydrol.
A convenient method of separating a mixture of organic compounds is recognized as liquid-liquid extraction, which involves the dispersion of a substance between two immiscible solvents using preferential solubility. Strategically using the differences in solubility of the interested solute, the compound can be transferred from one liquid part to the other during extraction. Organic acids and bases can be separated from each other by using an organic solvent like diethyl ether and a polar solvent such as water. Diethyl ether is an appropriate solvent since it wil...
The fifth experiment of the semester entails a synthesis reaction geared towards analyzing the structure of a product. The starting material is isopentyl alcohol. When reacted with acetic acid with sulfuric acid as a solvent, isopentyl alcohol produces isopentyl acetate, which is the goal product, as shown in the reaction below:
Friedel-Crafts Acylation is a chemical reaction, and it is a type of electrophilic aromatic substitution. Electrophilic Aromatic Substitution is a type of reaction that uses electrophile for aromatic ring from their substitution of one group of atoms. In other words, they can transfer acyl group to an aromatic ring. Friedel-Crafts has an acyl group that is attached to the structure that has aromatic ring. Acylation is used to give ketones. Carbonyl group makes electron to move back or move away in Friedel-Crafts Acylation, so it has not produced multiple acylations. Moreover, Lewis acid and acid anhydride are usually used in Friedel-Crafts Acylation. For example, the Friedel-Crafts Acylation of Benzene has a mechanism that the acyl halide reacts with the lewis acid, and
The catalytic process occurs at lower temperature anf offers higher selectivity but requires frequent regeneration of the catalyst. Then, the products are cooled and introduced into a pair of separators which separate the unreacted hydrogen. The unreacted hydrogen is compressed and recycle back to the feed and reactor. The products that leaving the separators are heated before introduced into a distillation column which the toluene is separated from the stream and recycle back to the...
Chromatography is the technical term for a set of laboratory approaches for the separation of mixtures (Solid/Liquid/Gas). The mixture is dissolved in a fluid which called the mobile phase, which carries it through a structure holding another material known as the stationary phase. The various constituents of the mixture transport at different velocities, causing them to separate. The separation is mainly based on differential partitioning between the mobile and it’s stationary phases. Subtle differences in a compound's partition coefficient result in differential retention time on the stationary phase and thus changing the separation (Tomer, et al., 1994).
The sample was subjected to steam distillation as illustrated in Figure 1. A total of 50ml of distillate was collected while recording the temperature for every 5.0 ml of distillate. The distillate was transferred into a 250ml Erlenmeyer flask and 3.0 g of NaCl was added. The flask was cooled and the content was transferred into a 250-ml separatory funnel. Then 25.0ml of hexane was added and the mixture was shaken for 5 minutes with occasional venting. The aqueous layer was discarded and the organic layer was left inside. About 25.0ml of 10% NaOH was then added and the mixture was shaken as before. The aqueous layer was collected and then cooled in an ice bath. It was then acidified with enough 6.00 M HCl while the pH is being monitored with red litmus paper. Another 25.0 ml of hexane was added and the mixture was shaken as before. The hexane extract was saved and a small amount of anhydrous sodium sulfate was added. The mixture was then swirled for a couple of minutes then filtered. A small amount of the final extracted was tested separately with 1% FeCl3 and Bayer’s reagent.
The purpose of this experiment is to compare the processes of distillation and fractional distillation to discover which procedure enables a more pure sample of ethanol to be collected from an ethanol/water mixture.