Manufacturing method of 2-hexanone
I. Introduction
2-hexanone is an important organic chemical raw material, which is widely used in the fields of medicine, pesticide, spice and dye. Therefore, it is of great significance to study the manufacturing method of 2-hexanone. In this paper, we will introduce the method of preparing 2-hexanone by hydroxyl aldehyde condensation reaction using acetone as raw material.
II.Experimental principle
Hydroxyaldol condensation reaction is a reaction in which an aldehyde or ketone, catalyzed by an acid or a base, undergoes a nucleophilic addition reaction with another molecule of aldehyde or ketone to produce hydroxyaldehyde, which is further dehydrated to produce an aldehyde or ketone. In this experiment, acetone under alkaline conditions undergoes hydroxyl aldehyde condensation reaction with another molecule of acetone to produce 3-hydroxy-2-butanone, which is further dehydrated to produce 2-hexanone.
III. Experimental Procedure
1. 100mL of acetone, 10g of sodium hydroxide and 50mL of water were added to a three-necked flask and heated to reflux with stirring.
2. After refluxing reaction for 2 hours, the pH was adjusted to neutral with hydrochloric acid, and the acetone was recovered by distillation to obtain brown oily material.
3. The oily material was washed with ether several times, then dried with anhydrous sodium sulfate, filtered and distilled to obtain 2-hexanone.
IV. Experimental results and discussion
1. Experimental results
In this experiment, 2-hexanone was prepared from acetone by hydroxyl aldehyde condensation reaction with 80% yield. The product was characterized by infrared spectroscopy and nuclear magnetic resonance to confirm the structure of the product.
2. Experimental Discussion
In the experiment, factors such as the amount of sodium hydroxide, reaction time, and pH value affected the experimental results. When the dosage of sodium hydroxide is too much, it will lead to the generation of by-products; the reaction time is too long, which will lead to the decomposition of the products; and the adjustment of pH value will also affect the purity of the products. Therefore, these conditions need to be strictly controlled in the experiment to obtain high quality 2-hexanone.
V.Conclusion
In this experiment, 2-hexanone was prepared by hydroxyl aldehyde condensation reaction using acetone as raw material with high yield and easy operation. By exploring the experimental conditions, it provides a reference for further optimizing the experimental conditions and improving the yield.
VI.Prospect
Although 2-hexanone has been successfully prepared in this experiment, there are still some shortcomings, such as the yield is not high enough and the by-products are more. Therefore, the follow-up study can further explore ways to optimize the experimental conditions to improve the yield and purity. In addition, other raw materials and routes can also be tried to develop more efficient and environmentally friendly manufacturing methods to provide stronger support for the wide application of 2-hexanone.
