Solvent

The chromatography was performed on an ACQUITY TM UPLC system (Waters Corp., Milford, MA, USA). The UPLC system included quaternary solvent manager, a binary pump, degasser, autosampler with an injection loop of 10 μL and a column heater-cooler. The separation was performed on Acquity UPLC BEH TM C18 column (50 × 2.1 mm, i.d., 1.7 μm, Waters, USA) maintained at 40 °C. a mobile phase of acetonitrile containing 0.1% formic acid and aqueous 5 mM ammonium acetate buffer containing 0.1% formic acid…

scaffold showed the best results in terms of catalytic activity (70% yield) and enantioselectivity (98% ee) (Entry 2, Table 1). In further experiments using (R)-1b as the optimal catalyst, different solvents were examined (Entries 6–10). In general, excellent enantioselectivity was obtained in all the solvents tested in this study. Among them, m-xylene proved to be the best in terms of yield (75%) and asymmetric induction (99% ee) (Entries 8–10). Further improvement of the yield was achieved by…

amount of components in a solution or to identify an unknown compound. The principal behind TLC is when different compounds are placed on silica gel or alumina, (stationary phases) they will travel different distances when eluted with the proper solvent. According to ChemistryGuide, this is because the more polar compound has a stronger interaction with the silica gel due to its polar properties. This makes it easier to drive the eluent away from its binding area. An eluent is a liquid that…

of hexane, and the one labeled “organic solvent” is placed under the column in order to collect the hexane. 10. Use a pipet to slowly add 1ml of hexane in increments to avoid any overflowing. 11. Keep adding and collecting the hexane until the yellow ferrocene reaches the bottom of the column bed, and immediately start to collect it in the sample vial labeled “F” 12. After all of the ferrocene has been collected, place the flask labeled “organic solvent” under the column 13. Repeat Steps 9…

In Experiment 12B we used an umpolung reagent in an umpolung synthesis to synthesize benzoin from benzaldehyde. Umpolung synthesis is a synthetic approach that allows us to switch the identity of a reacting species. For example, the normal chemical reactivity of a nucleophile can be switched to one of an electrophilic compound. Two common agents are cyanide and thiamine (Vitamin B). The mechanisms for both agents are the same. In this experiment, thiamine was used to turn benzaldehyde, an…

Caffeine can be initially extracted from tea leaves by boiling it in water and isolated through liquid-liquid extraction with the usage of dichloromethane and other solvents (Rebecca, Candace Seshiah, & Tissopi, 2006). Water extraction and organic solvents extraction, that uses chemicals such as methylene chloride and dichloromethane, are the most common methods for further removal of caffeine from tea (Lou et al., 2012). The objectives of this experiment…

Purpose: The purpose of this laboratory was to synthesize isopentyl acetate, commonly known as banana oil, in a reaction of methanol and isopentyl alcohol catalyzed by sulfuric acid. Through this Fischer esterification reaction, it was possible to learn about using a Reflux condenser to run a reaction as well as purifying the product through various washes and extractions along with simple distillation. In addition, the product of the experiment was carefully analyzed based upon boiling point,…

The heterocyclic compounds naming tetrahydrocarbazoles having the significant biological properties. The newly substituted tetrahydrocarbazole derivatives were prepared from substituted phenylhydrazine and cyclohexanone in glacial acetic acid under reflux. These intermediates on reaction with substituted aromatic acid chlorides in alkaline media finally converted to N-Substituted tetrahydrocarbazoles. Fifteen compounds are synthesized and charaterized by their melting point (MP), IR, NMR, MS…

Questions 1. What reaction was carried out in this lab and what reagents were used? 2. What techniques were used to purify and identify the product of the reaction? 3. Describe acid-base extraction and how it was being used in this experiment? 4. Describe recrystallization and how it was being used in this experiment? 5. Describe mixed melting point and how it was being used in this experiment? 6. What was the identity of the unknown acid? 7. What yield and percent yield were obtained?…

the positions of the different pigments relative to original line where you put the spot of leaf extract. (Bazil) Which pigment is the most soluble and which is the least soluble in petroleum ether? Each pigment has a different solubility in the solvent due to their unique molecular structures and differing polarities. Solubility plays in an important role in determining unknown pigments in a sample. In the case of the lab, the most soluble pigment should have the highest Rf value and should…