6-Endo-Dicarboxylic Anhydride Lab Report

The melting point of the product was observed to be 139.5 °C. The theoretical yield of the product is 152 °C (University of South Carolina Department of Chemistry and Biochemistry). The melting point percent difference was calculated by subtracting the theoretical melting point from the actual melting point, dividing the result by the theoretical melting point, and multiplying the result by 100%. The melting point difference was 8.22%. Example calculations are shown

Benzyne Formation and the Diels-Alder Reaction Preparation of 1,2,3,4 Tetraphenylnaphthalene Aubree Edwards Purpose: 1,2,3,4-tetraphenylnaphthalene is prepared by first producing benzyne via the unstable diazonium salt. Then tetraphenylcyclopentadienone and benzyne undergo a diels-alder reaction to create 1,2,3,4-tetraphenylnaphthalene. Reactions: Procedure: The reaction mixture was created. Tetraphenylcyclopentadienone (0.1197g, 0.3113 mmol) a black solid powder, anthranilic acid ( 0.0482g, 0.3516 mmol) a yellowish sand, and 1,2-dimethoxyethane (1.2 ml) was added to a 5-ml conical vial.

The aims of this experiment were to separate and locate the enzyme N-acetyl-β-D-Hexosaminidase from protein sample #15 and determine the specific activity of the enzyme within the sample. DEAE cellulose anion exchange chromatography was used to separate proteins from within sample #15. The initial separation was performed through the addition of Tris/HCl buffer pH 7.2 and yielded a peak consisting of positively charged proteins. Salting out was performed with Tris/HCl pH 7.2 1.0 M salt buffer and eluted negatively charged proteins. Peaks also represented the highest amount of a negatively and positively charged protein respectively.

Chem 51 LB Experiment 3 Report Scaffold: Bromination of Trans-Cinnamic Acid 1. The goal of this experiment was to perform a halogenation reaction through the addition of two bromides from pyridinium tribromide. This was accomplished by reacting trans-cinnamic acid with pyridinium tribromide. After the reaction took place, melting point analysis was conducted to find out the stereochemistry of the product, which could either be syn-addition, anti-addition, or syn + anti-addition. 2.

As seen in table 1, the theoretical yield was .712 g of C_17 H_19 NO_3. The % yield of this experiment was 7.51 % of C_17 H_19 NO_3. . This low yield can be explained from a poor recrystallization technique combined with potential contamination. Throughout the experiment, the mixture changed color from green, orange, to yellowish lime, and eventually clear.

Tertiary alkyl halides tend to give a mixture with both inverted and retained configurations at reaction centers. This is because this reaction proceeds through a stable carbocation intermediate and the carbon at the reaction center goes to sp2 hybridized state (planar geometry). The incoming nucleophile can attack from both sides of the plane and can give two products with retained and inverted configuration. If there is a partial interaction with the leaving group (nucleofuge) with carbocation there will be more product with inverted configuration and if there is no interaction with leaving group racemic mixture can be obtained. The rate of the reaction depends on the formation of a carbocation (which is the slow step) and there is one molecule

The actual yield of the reaction was 4.411 grams of copper and was obtained through the experiment

The purpose of this experiment was to learn about metal hydride reduction reactions. Therefore, the sodium borohydride reduction of the ketone, 9-fluorenone was performed to yield the secondary alcohol, 9-fluorenol. Reduction of an organic molecule usually corresponds to decreasing its oxygen content or increasing its hydrogen content. In order to achieve such a chemical change, sodium borohydride (NaBH4) is used as a reducing agent. There are other metal hydrides used in the reduction of carbonyl groups such as lithium aluminum hydride (LiAlH4).

I believe that it is not common to obtain an exact 100% yield because that would mean that the chemists doing the experiment would have to do everything perfectly without any flaws. Like measuring off by a slight amount or leaving behind some of the substance if transferring it over to another flask or beaker. A person could not do something so perfectly because humans always do errors while doing things, it would be very unlikely for a chemists to get a 100% yield after for a chemical reaction. 6. The percentage yield was not 100%.

The possible explanations and changes to make are similar to the previous questions. Conclusion and Future Experiment 18. The identity of the product and unknown were 4-tert-butylbenzyl phenol ether and tert-butyl phenol respectively. The key to making this discovery was the melting point and TLC results!

This means that there were a few errors made during the exercise. While we cannot pin point the main reason why the percent yield is so high, there’s a few possibilities. First, it might not all be CuO, there could have still been water in the filter paper and precipitate when we took it out of the funnel which would cause the mass to change and affect the percent yield. But the main possibility as to the high percent yield is that there is still some Cu(OH)2 in the precipitate that never got broken down when heated which affected the percent

The literature melting point range of methyl trans-cinnamate is ~34-38oC (Aldrich).4 The obtained melting point of the crude was 34.5-35.5oC, which is a highly narrow range of less than 1oC difference and it also falls within the expected melting point range. Hence, the crystal lattice structure of the product is largely intact, requiring an even amount of thermal energy to melt the sample. The experimental melting point range indicates the crude product is relatively pure with minimal impurities. The percent yield was satisfactory, having a 68% yield. To optimize this yield, consider the steps in how the reagents are introduced to the reaction mixture in terms.

This was proved by utilizing the IR spectrum to verify the C =O was not in the final product as it lacked the 1640 cm-1 peak. The melting point of 113-115 degrees C proved that the final product obtained was the E-Stilbene. The TLC plate proved that the E and the Z product was produced, show cased by the double intensity of the DCM spot to the final product’s spot, both which had an Rf of 0.92. The double intensity proved that both products were produced, but through heating and filtering, the Z-Stilbene was

Verna Wang Hannah Palmer CHEM 101-069 Lab 11-19-16 Stoichiometry and Limiting Reagents Lab Report Purpose: We are using the reaction of sodium hydroxide and calcium chloride to illustrate stoichiometry by demonstrating proportions needed to cause a reaction to take place. Background: Just like a recipe would call for a specific amount of one ingredient to a specific amount of another, stoichiometry is the same exact method for calculating moles in a chemical reaction. Sometimes, we may not have enough of or too much of one ingredient , which would be defined as limiting and excess reagent, respectively.

The chemistry of heterocycles compounds is one of the most complexes of branches of chemistry. It is equally interesting for its theoretical implication for the diversity of its synthetic procedure and for the physiological and industrial significance. Synthetic heterocycles chemistry has influenced almost every place of human life and the heterocycles compounds have found their application in diverse field as medicine, agriculture, polymer, and various industries. The proposed work is in context with the compounds having 1,3,4-ox diazoles moiety.