Benzoin

compound, which was about 130 °C – 139 °C. At this point the suspected organic compound was benzoin, and the melting points of the two compounds, benzoin and the unknown, as well as the 50:50 mixture of each, were obtained. The unknown compound, along with the benzoin, had identical melting points of 133.7°C – 134.9°C, while the 50:50 mixture had a melting point of 133 °C – 134.3 °C. The true melting point for benzoin is 132°C, generating a .75 percent error.

Multi-Step Synthesis of Benzilic Acid from Benzoin Abstract: The main purpose of this experiment was to convert a secondary alcohol to a ketone, utilizing a mild and selective oxidizing agent. In addition, this converted alpha diketone was then subjected to rearrangement to a carboxylate salt, then acidification, to produce an alpha-hydroxyacid. In this experiment, benzoin was used and converted into benzil, which was then used to synthesize benzillic acid. The yields were not ideal: .081g of benzil-

Title: Oxidation of Benzoin and Rearrangement of Benzil to Produce Benzilic Acid Abstract The objective of the lab was to produce benzilic acid from benzoin. Benzoin was successfully oxidized with nitric acid to form benzil. The percent yield of benzil was 59.26% and the melting point range was 94.1-95.5°C. The literature melting point of pure benzil is 95°C, which indicates the correct product was obtained. Benzil was then rearranged using potassium hydroxide to form benzilic

substance. Based on the rapid heating rate of the test, it was determined that the unknown substance was either Trans-cinnamic acid or Benzoin due to the wider melting point range at 132℃. After the second, slower heating rate, it was determined that the unknown might be Benzoin due to the wider melting point range. However, when experimented with the unknown and the Benzoin, the 50/50 mixture melted before the other 2 compounds had begun to change states because it was acting as an impurity instead of

Synthesis of benzilic acid from benzoin utilizing a multi-step reaction. Names: Arian Karim TA Name: Sayantan Das Lab Day & Time: Thursday 7:30-11:40 Lab Section #: Abstract The main purpose of this experiment was to synthesize benzilic acid from benzoin. This requires a multistep synthesis with benzyl as an intermediate product. The first step required HNO3 as an oxidizing agent and the second step required KOH and HCl. The percentage yields of benzil and benzilic acid were 59.5%

The reduction of an aldehyde or ketone with sodium borohydride is an experiment that usually produces a large yield of alcohol. The procedure involves dissolving an excess amount of sodium borohydride in 95% ethanol and then adding a benzil to the solution. Sodium borohydride reduces the carbonyl groups in the benzil and the acidification produces a diol or two secondary alcohols. The overall purpose of this experiment was to determine the favored diastereomer in the reduction of benzyl by sodium

Results: Limiting Reactant: Eq 1 Limiting reactant = Benzoin Theoretical yield of Benzil: Eq 2 Theoretical Yield Benzil | 0.296 g | Mass of Crude Benzil | 0.188 g | Mass of Final Benzil | 0.127 g | % Yield | 43% | % Recovery | 66% | Table 1: Mass of crude/final Benzil, % yield, and % recovery Percent Yield: % Yield = (Final product/Theoretical product) x 100 Eq 3 = (0.127 g/0.296 g) x 100 = 43% yield Percent Recovery

Introduction: Diazoaminobenzene can be prepared by dissolving two equivalents of aniline in three equivalents of hydrochloric acid and one equivalent of sodium nitrite in aqueous solution followed by two equivalents of sodium acetate. Reaction: Procedure: 1. In a 100 mL conical flask place 20 mL of water, 5 mL conc. HCl and 3.5 g aniline. 2. Shake vigorously and add about 15 g crushed ice. 3. In a test tube dissolve 1.3 g sodium nitrite in 3 mL water. 4. Add this sodium nitrite solution

Benzil Reduction Introduction The objective of the experiment was to reduce Benzil, using sodium borohyride as the reducing agent. In a benzil reduction, there are five possible products than can occur, specifically a racemic mixture of benzoin, racemic mixture of hydrobenzoin, or meso-hydrobenzoin. Therefore, three different tests were conducted in determining the identity of the product: melting point, thin light chromatography, and infrared spectroscopy. (a) Mechanism and reaction equation

Discussion The percent yield of the crude product from experiment seven was 77.6%. The melting point of the crude product was 100 ° C – 119.2 ° C. The melting point range was 19.2 ° C. The percent yield of the pure product from experiment seven was 63.2%. The melting point was 100° C – 108.2 °C. The melting point range was 8.2 ° C. The percent yield of benzilic acid from experiment 8 was 66.9%. The melting point was 139.9° C – 143.3 °C. The melting point range was 3.4 °C. According to PubChem, the