Advantages And Disadvantages Of NMR Spectroscopy

The objective of this lab was to create a ketone through an oxidation reaction using a using a secondary alcohol and oxidizing agent in order to use that ketone in a reduction reaction with a specific reducing agent to determine the affect of that reducing agent on the diastereoselectivity of the product. In the first part of this experiment, 4-tert-butylcyclohexanol was reacted with NaOCl, an oxidizing agent, and acetic acid to form 4-tert-butylcyclohexanone. In the second part of this experiment, 4-tert-butylcyclohexanone was reacted with a reducing agent, either NaBH4 in EtOH or Al(OiPr)3 in iPrOH, to form the product 4-tert-butylcyclohexanol. 1H NMR spectroscopy was used to determine the cis:trans ratio of the OH relative to the tert-butyl group in the product formed from the reduction reaction with each reducing agent. Thin-layer chromatography was used in both the oxidation and reduction steps to ensure that each reaction ran to completion.

Reducing sugars are monosaccharides that have equilibrium with the straight-chain and cyclic form, which the sugar engages in an oxidation-reduction reaction with Cu2+ (C. Bissonnette, 2011). Through this test, one is able to determine that the unknown solution #128 is a non-reducing sugar because the results show that the test turned out positive, and reducing sugars cause negative tests to occur.

Introduction: The fundamental techniques of organic chemistry lab, commonly known as SIPCAn, include separation, isolation, purification, characterization, and analysis (1). Through SIPCAn, students learn the fundamental techniques of organic chemistry laboratory. Mastering these techniques are necessary in order to perform more complicated experiments and to carry out organic reactions and synthesis. The information gained from SIPCAn included boiling point, melting point, and density can be used to identify unknown compounds. Simple distillation was used to purify a compound by separating it from a

There is a demand for artificial sweeteners because people want to control their intake of sugar. Saccharin, cyclamates, aspartame, as well as Dulcin, are some sugars that fulfill the need for sweeteners to be of low caloric content. Some of the sweeteners, such as Dulcin, are now considered to yield undesirable health effects with long term use. Dulcin is 250 times sweeter than table sugar. The synthesis of Dulcin was done in order to calculate the percent yield. The lesson of this experiment was to learn how to synthesize Dulcin from phenetidine and potassium cyanate (KOCN). During the experiment, Dulcin was synthezided in the presence of water and acetic acid, which were the solvents. Hydrocyanic acid (HOCN) was formed from the acetic acid and KOCN (Scheme 1 equation 1). Then the HOCN will react with phenetidine to make Dulcin (Scheme 1 equation 2).

In this experiment, the Fischer Esterification of an unknown acid and an unknown alcohol was used to prepare an unknown ester. Sulfuric acid was used as a catalyst in the reaction which then was put under reflux. After cooling, the pH of the solution was raised to approximately 8 using sodium carbonate. Diethyl ether was added, then the aqueous layer was removed and the organic layer was washed with sodium chloride. The aqueous layer was removed again and sodium sulfate was added. The unknown product was then identified using gas chromatography (GC) to obtain the retention time.

Analysis: In this experiment, every substance tested positive for at least 1 organic compound. Corn oil tested positive for lipids. Honey and oats tested positive for starch. Honey, apple juice, and unknown 1 tested positive for sugar. Egg white, gelatin, and unknown 2 all tested positive for proteins. So, not a single substance didn't test positive for at least 1 organic compound. All the indicators used in this experiment change color when in the presence of a compound; therefore, they chemically react with the compound. No errors were made during this experiment

(Q3:Purification) Product was purified via crystallization and using ice-cold water ensured product remain intact while impurities were washed into the filtrated liquid. The results gathered were measured against already scientifically established melting points of the product, the standard solutions provided, and retention factor (Rf) values to conclude the unknown nucleophile used in the beginning was 4-methoxyphenyl.

Statistical analysis for the animal studies. Our selection of 10 animals per time point is based on the group variance observed in our preliminary studies employing diet models. For example, an n = 10 provides 95% power (alpha of 0.05) to detect differences in ALT values of at least 30 U/L between two means with a standard deviation of 10 (two-tailed t-test). For endpoints such as ALT values, caspase positive cells, etc., in different animal populations, parametric analysis will be performed. ANOVA will be employed given the presence of multiple groups, and a Bonferroni test will be used to correct for multiple comparisons. If the distribution of values is unsuitable for a parametric analysis, we will perform a Kruskal-Wallis test for nonparametric data. If the data show a strong trend towards significance (e.g., p < 0.1) with reproducible data except for a rare outlier, we can consider increasing the number of animals per group. The number added will be calculated using the mean and standard deviation (SD) from the existing data

The purpose of this lab was to carry out a dehydration reaction of 2-methylcyclohexanol by heating it in the presence of phosphoric acid and determining which alkene product would be the major product. Methylcyclohexanols were dehydrated in an 85% phosphoric acid mixture to yield the minor and major alkene product by elimination reaction, specifically E1. The alkenes were distilled to separate the major and minor products and gas chromatography was used to analyze the results and accuracy of the experiment. The hypothesis was the major product of the reaction would be the most substituted product. This conclusion was made because of

The products of interest within this experiment are 2-methyl-1-butene and 2-methyl-2-butene from sulfuric acid and phosphoric acid catalyzed dehydration of 2-methyl-2-butanol. The reaction mixture was then separated into its separate alkene components by steam distillation and then analyzed by gas chromatography (GC), Infrared Radiation (IR) spectroscopy, and Nuclear Magnetic Resonance (NMR) imaging. Gas chromatography is an analytical technique that is able to characterize if specific compounds exist in a reaction mixture, even if they are in low quantities, assess how much of a compound exists within a reaction mixture relative to other components within the sample, and determine the purity of an isolated product. In the case of this experiment, gas chromatography is used to analyze how pure the alkene reaction sample was and if any remnants of impurities or 2-methyl-2-butanol remained in the sample after isolation of alkene components.

In neuropsychology and behavioral neuroscience, multiple methods have been used to create relations between brain function and behavior in addition to studying how the brain is stimulated to produce action. Static and Dynamic imagery techniques of observation have been used over the years to map out brain regions and understand relationships between internal brain activity and external behavior. However, one brain study method has proven to be a groundbreaking process that has managed to create other derivative methods and increased human understanding of the effects of brain activity alterations. This method is known as Magnetic Resonance Imaging (MRI).

For this experiment, Alcohol D and Acid 2 reacted in the presence of concentrated sulfuric acid, resulting in a colorless solution with brown layer on top. After washes with sodium bicarbonate and brine, the pale-yellow liquid product was dried and then distilled. Distillation resulted in two colorless fractions, the second of which had a boiling point of 69-70 ˚C. This boiling point is unrealistic for any compound obtained in this experiment, so it was not used in identifying the product. After distillation, both fractions were spectroscopically analyzed. The IR and NMR spectra obtained for both fraction were identical, meaning both fractions contained exactly the same substance. Both fractions also smelled the same, like piña colada, therefore confirming this conclusion. This outcome also meant that the amount of product synthesized was 5.7393 g.

In this experiment, methyl benzoate was synthesized from benzoic acid and methanol with acid catalyze using Fisher Esterification. First benzoic acid and methanol were mixed in 100 mL round bottom flask. We cooled the mixture in ice and poured 3 mL of conc. H2SO4 and swirled to mix compounds. Then we refluxed the mixture for 1 hour. We let the solution cool and then decanted into a separatory funnel containing 50 mL of water and rinsed the round bottom flask with 35 mL of tert-butyl methyl ether and added that to a separatory funnel. We shook and vented thoroughly and drained the aqueous layer which contained a bulk of methanol and H2SO4. We washed the solution in the separatory funnel with 25 mL of water, followed by 25 mL of sat. sodium bicarbonate

We are required to obtain certain amount of nutrients from food. Food can simply divide into 2 groups, macro-nutrients and micro-nutrients composition. Both of the groups mentioned do affect the metabolism rate. According to Hulbert and Else, dietary fatty acid will affect the metabolism rate and some of the polyunsaturated fatty acid will increase the metabolism rate (1999). Meanwhile, different kinds of animals have their own unique requirement for macro-nutrients, such as proteins, carbohydrates and fat. Moreover, most of the food intake is driven by achieving the required protein intake. Animals on a low protein diet will over eat carbohydrates and fat until the protein requirement has been satisfied. If this case

INTRODUCTION: technique and applications for sugar crhomatography have continued to advance steadily since publication of previous edition in 1969. Though thin layer chromatography has become most popular for rapid identification.