Magnesium Synthesis

Magnesium (1.5 g) was stirred vigorously, to combat oxidation and pulverize the by-product magnesium sulfate, in a 250 mL round bottom flask for 5 to 10 minutes, then fit with reflux apparatus – including CaCl2 Drying Tube, 125 mL Dropping funnel, Claisen adapter, and thermometer adapter – and add anhydrous ethyl ether (40mL) through the dropping funnel. Bromobenzene (3mL) and Anhydrous Ethyl Ether (15mL) was added to the reaction flask through the dropping funnel dropwise and in halves. Reflux the reaction chamber for 30 minutes over a steam bath. Benzophenone (9.1g) was dissolved in Diethyl Ether (100mL) and added to the reaction chamber and reflux was initiated again for 15 minutes. The reaction was cooled in an ice bath to ambient temperature. A cold acidic solution was created with ice (about 50mL) and Sulfuric Acid (4.5 mL) diluted with water to create the volume of the total solution (~75mL) add this acidic solution to the reaction flask through the condenser dropwise making sure to stir the reaction mixture during the addition. Pour the final biphasic reaction mixture into a Separatory Funnel (500mL), extract the aqueous layer with two portions of diethyl ether (50mL), dry the ether layers over Magnesium Sulfate, Vacuum Filter away the Magnesium Sulfate salts store product ethereal solution. The crude solid was, …show more content…
• The addition of bromobenzene to the initial solution lightened the solutions color to a white-yellow.
• Thirty minutes of refluxing the ethereal solution boiled it and changed the color to dark brown.
• The dropwise addition of Benzophenone led to a “red wine” perceived color change, then to a bright pink and then bright pink color separated into a layer we assumed was the charged intermediate.
• Stirring the solution on an ice bath yielded orange-colored precipitate on top of the pink