Making raspberry perfume

The script begins with an introduction to the channel's history of creating various chemicals with diverse scents, from pleasant to unpleasant. The speaker expresses an interest in creating a unique perfume using raspberry ketone, a naturally occurring compound in red raspberries that is challenging and expensive to extract due to its low concentration. Instead, they opt to synthesize it from cheaper precursors like benzene, which is derived from crude oil. The process involves several steps, starting with 4-Hydroxybenzaldehyde, and includes an aldol condensation reaction catalyzed by sodium hydroxide. The speaker also mentions the practicality of purchasing raspberry ketone as a weight loss supplement online, despite the lack of evidence for its efficacy.

The second paragraph delves into the actual laboratory process of synthesizing raspberry ketone. It starts with the preparation of a sodium hydroxide solution and the creation of a clear solution of 4-Hydroxybenzaldehyde in acetone. The aldol condensation reaction is performed, resulting in an intermediate molecule. After allowing the reaction to complete, the mixture is treated with hydrochloric acid to neutralize the base and stop further polymerization, aiding in the purification of the desired product. The product is then separated from impurities through vacuum filtration and recrystallization, resulting in a pale yellow product with a modest yield and purity.

In the third paragraph, the process of recrystallization is described to increase the purity of the synthesized raspberry ketone. The speaker attempts to dissolve the product in a mixture of water and ethanol, adjusting the solubility to precipitate pure crystals. Despite the presence of some tar at the bottom, the crystals are filtered, dried, and the yield is improved. A second recrystallization is performed to achieve a higher purity, resulting in a white crystalline product, although still with some orange impurities.

The fourth paragraph focuses on the final step of synthesizing raspberry ketone, which is the hydrogenation reaction. The speaker details the process of generating hydrogen gas using sodium hydroxide and aluminum foil, and the setup for the reaction involving the intermediate molecule, ethyl acetate, anhydrous sodium acetate, and palladium on carbon as a catalyst. The reaction is carefully controlled to ensure no air is present, which could lead to an explosion due to the pyrophoric nature of the palladium on carbon. The reaction is monitored by the absorption of hydrogen, indicating the progress of the hydrogenation.

This paragraph describes the post-reaction steps to isolate the synthesized raspberry ketone. The palladium on carbon and sodium acetate are filtered out, and the remaining solution is concentrated by evaporating the ethyl acetate. The speaker notes the faint raspberry smell that emerges as the ethyl acetate evaporates, indicating the presence of the desired compound. The process concludes with the solidification of the remaining oil into an off-white powder, which is the synthesized raspberry ketone.

The final paragraph discusses the challenges faced in crystallizing the synthesized raspberry ketone and the subsequent steps to create a perfume. Despite attempts to recrystallize the ketone, it remains in an oily state, leading to a low yield. The speaker then moves on to the perfume-making process, where the ketone is dissolved in ethanol to create a concentrated solution. The resulting perfume is tested and found to have a faint sweet and fruity smell, but it lacks the characteristic raspberry aroma, highlighting the complexity of replicating natural scents with single compounds. The video concludes with the speaker's intention to explore the creation of other scent compounds, possibly venturing into less pleasant odors.