To Conduct A Benzophenone Reduction Using Todium Borohydride

The Purpose of this experiment is for the students to learn how to use sodium borohydride to reduce benzil to its secondary alcohol product via reduction reaction. This two-step reaction reduces aldehydes by hydrides to primary alcohols, and ketones to secondary alcohols. In order for the reaction to occur and to better control the stereochemistry and yield of the product, the metal hydride nucleophile of the reducing agents such as LiH, LiAlH4, or NaBH4 must be carefully chosen. Being that LiAlH4 and NaBH4 will not react with isolated carbon-carbon double bonds nor the double bonds from aromatic rings; the chosen compound can be reduce selectively when the nucleophile only react with

In this lab, liquid-liquid extraction was performed to isolate a mixture of benzocaine and benzoic acid. 2.0107 grams of the mixture was first weighed out for the trials. When HCl was added to the mixture for the first acid extraction of benzocaine, an emulsion formed during inversion and venting that prevented a defined separation of the two layers. 8 mL of water was therefore added before continuing the extraction. The addition of NaOH then turned the top aqueous layer basic, indicated by the pH strips that turned blue when tested. A vacuum filtration isolated 0.29 grams of benzocaine and a MelTemp apparatus measured the crystal’s melting point ranges to be 85.1C-87.4C. For the base extraction of benzoic acid, the aqueous layers were retrieved

An automatic pipet was used to measure 0.450 mL water and 0.165 mL acetic anhydride and was added to the conical vial. A spin vane was placed into the vial and an air condenser was attached.

* By using the dropper and measuring cylinder, 7 ml sodium carbonate solution was added to the test tube

NH3. Add 20 mL water to the beaker by filling and emptying the 10 mL cylinder into the beaker

Three grams of a mixture containing Benzoic Acid and Naphthalene was obtained and placed in 100 ml beaker and added 30 ml of ethyl acetate for dissolving the mixture. A small amount (1-2 drops) of this mixture was separated into a test tube. This test tube was covered and labelled as “M” (mixture). This was set to the side and used the following week for the second part of lab. The content in the beaker was then transferred into separatory funnel. 10 ml of 1 M NaOH added to the content and placed the stopper in the funnel. In the hood separatory funnel was gently shaken for approximately one minute and vent the air out for five seconds. We repeated the same process in the same manner one more time by adding 10ml of 1M NaOH.

After the twenty minutes elapsed, the flask was cooled to room temperature and then titrated with the remaining NaOH until the colorless solution remained pink. The final volume was then recorded. While solution #1 was heating the same process was repeated with solution#2 and the second burette

The next step in this lab is to rinse the Erlenmeyer flask with distilled water down the drain and then repeat the experiment, this time adding 10 ml of 0.10M KI and 10 ml of distilled water to the flask instead. The flask should again be swirling to allow the solution to succumb to the same temperature as the water bath and once it has reached the same temperature, 10 ml of 3% H2O2 must then be added and a stopper must be immediately placed on the flask and recording should then begin for experiment two. After recording the times, the Erlenmeyer flask must then be rinsed again with distilled water down the drain. After rinsing the flask, the last part of the lab can now be performed. Experiment three is performed the same way, but instead, 20 ml of 0.10 ml M KI and 5 ml of distilled water will be added and after the swirling of the flask, 5 ml of 3% H2O2 will be added. After the times have been recorded, data collection should now be complete.

2. Fill a flask with pure water (0% sugar), another with 0.2M water, another flask with 0.4 M water, and another flask with 0.8M water.

After the initial mixture has refluxed, 9.11 grams of benzophenone was dissolved in 100 mL of anhydrous ether in a beaker and was then transferred into the separatory on the reflux apparatus. This solution was then added to the Grignard reagent at a drop wise rate while stirring. After the benzophenone was added, the mixture was then refluxed for 15 minutes on a heating mantle.

One milliliter of 6.00-M phosphoric acid was placed into a 125-mL Erlenmeyer flask using a volumetric pipette. Using a slightly larger pipette, six milliliters of 3.00-M sodium hydroxide was transferred into a 50-mL beaker. Then a disposable pipette was used to slowly mix the sodium hydroxide into the phosphoric acid while the solution was swirled around. Then both the beaker and flask were rinsed with 2-mL of deionized water and set aside. A clean and dry evaporating dish was weighed with watch glass on a scale. Then the solution was poured into the dish and the watch glass was placed on top. The solution was then heated with a Bunsen burner to allow for the water to boil off to reveal a dry white solid. After the dish cooled to room temperature it was once again weighed and the new mass was recorded.

The solution was shaken well to remove any carbon dioxide Procedures for buffering 1. 25 mL of water was poured into the beaker using the graduated cylinder 2. the pH was measured using the pH probe and recorded under the “0 Drop HCI” in the table 3. 5 drops of 0.1M HCI was added, one drop at a time and swirled after each drop 4. the pH was measured again and the results recorded under 5 drops 5.

Separately, 20.0 mmol of benzophenone was combined with 10 ml of anhydrous ether. The mixture had a slightly layered appearance. Using a pipette dropper, drops of the benzophenone ether solution were added to the original Grignard reagent solution. Drops were added slowly, contact caused a slightly bubbling.

The lab’s purpose is to standardize a prepared sodium hydroxide solution and use it to determine the molarity of an unknown acid. Moreover, acids and bases react with the known stoichiometric ratios based on the coefficients of the balanced chemical reactions. If the stoichiometric ratio of an acid-base reaction is known the unknown concentration can be determined, however the reaction must have gone through completion and the number of moles of one of the components needs to known. The pH scale can be used to determine the change in concentration of an acid or base. The pH scale is calculated through the formula (pH = -log[H+]). Furthermore, when an acidic compound interacts with basic compound, the concentration of hydrogen decreases, therefore

The purpose of this experiment is to study an electrophilic aromatic substitution. With observing this substitution, the identity of the major product will be discovered. The method used to reach the purpose of the experiment is a TLC. The nitration of methyl benzoate with a mixture of sulfuric acid and nitric acid will be performed in the experiment. NO2 is the electrophile in the experiment, and it is an electron withdrawing group that makes the methyl benzoate less reactive. The NO2 group in this nitration can be added to three different positions —ortho, para, or meta. When the NO2 is added, it makes a methyl nitrobenzoate. The weight recorded of methyl benzoate in the start of the experiment is 3.397 grams. The weight of the crude product