The Diels-Alder experiment was conducted in laboratory to produce a bridged polycyclic anhydride. The Diels-Alder reaction takes place to combine a diene; the electron rich nucleophile with a dienophile which is “diene loving”, with at least one strong electron-withdrawing group1. In this experiment, anthracene is used as the diene which combines with maleic anhydride, the dienophile, to form
The sole purpose of performing the lab was to utilize aldol condensation reactions to synthesize a cyclopenta-dienone, while using UV spectrophotometry and computer visualization to further understand the dienone. In the beginning of the lab, the tetraphenylcyclopentadienone (TPCP) was synthesized using dibenzyl ketone and benzyl under extremely basic conditions. The synthesis process could be further understood by observing the mechanism portrayed in Figure 1. According to the figure, the dibenzyl ketone will first loose an alpha hydrogen to form the enolate intermediate.
The goal of this two week lab was to examine the stereochemistry of the oxidation-reduction interconversion of 4-tert-butylcyclohexanol and 4-tert-butylcyclohexanone. The purpose of first week was to explore the oxidation of an alcohol to a ketone and see how the reduction of the ketone will affect the stereoselectivity. The purpose of first week is to oxidize the alcohol, 4-tert-butylcyclohexanol, to ketone just so that it can be reduced back into the alcohol to see how OH will react. The purpose of second week was to reduce 4-tert-butylcyclohexanol from first week and determine the effect of the product's diastereoselectivity by performing reduction procedures using sodium borohydride The chemicals for this lab are sodium hypochlorite, 4-tert-butylcyclohexanone
The isomerization procedure was done in order to create dimethyl fumarate from dimethyl maleate. Dimethyl maleate and dimethyl fumarate are cis and trans isomers, respectively. This procedure was done via a free radical mechanism using bromine. The analysis of carvones reaction was done in order to identify the smell and optical rotation of the carvone samples that were provided. The odor was determined by smelling the compound and the optical rotation was determined using a polarimeter.
Alcohol, which is the nucleophile, attacks the acid, H2SO4, which is the catalyst, forming oxonium. However, the oxonium leaves due to the positive charge on oxygen, which makes it unstable. A stable secondary carbocation is formed. The electrons from the conjugate base attack the proton, henceforth, forming an alkene. Through this attack, the regeneration of the catalyst is formed with the product, 4-methylcyclohexene, before it oxidizes with KMnO4. In simpler terms, protonation of oxygen and the elimination of H+ with formation of alkene occurs.
Discussion and Conclusions: Interpreting these results have concluded that relative reactivity of these three anilines in order of most reactive to least reactive go; Aniline > Anisole > Acetanilide. Aniline, has an NH2 , the most active substituent , and adds to any ortho/para position available on the ring. This data is confirmed with the product obtained, (2,4,6 tribromoaniline, mp of 108-110 C). As for anisole, it has a strongly activating group attached, OMe an alkoxy group, and it added in two of the three available spots, both ortho. The results conclude: (2,4-Dibromoanisol mp 55-58 C ). Acetanilide has a strong activating group attached, acylamino group, but this group is large and the ortho positions are somewhat hindered so the majority of the product obtained added at the para position, results conclude: (p-bromoacetanilide mp 160-165 C). Since all the substituents attached to the aromatic rings were activators the only products able to be obtained were ortho/para products.
Scheme 1. Formation of the Diels-Alder adduct with maleic anhydride and (-)-α-phellandrene. The IR spectrum that was obtained of the white crystals showed several functional groups present in the molecule. The spectrum shows weak sharp peak at 2865 to 2964 cm-1, which is often associated with C-H, sp3 hybridised, stretching in the molecule, peaks in this region often represent a methyl group or CH2 groups. There are also peaks at 1369 cm-1, which is associated with CH3 stretching.
This week’s lab was the third and final step in a multi-step synthesis reaction. The starting material of this week was benzil and 1,3- diphenylacetone was added along with a strong base, KOH, to form the product tetraphenylcyclopentadienone. The product was confirmed to be tetraphenylcyclopentadienone based of the color of the product, the IR spectrum, and the mechanism of the reaction. The product of the reaction was a dark purple/black color, which corresponds to literature colors of tetraphenylcyclopentadienone. The tetraphenylcyclopentadienone product was a deep purple/black because of its absorption of all light wavelengths. The conjugated aromatic rings in the product create a delocalized pi electron system and the electrons are excited
Purpose/Introduction: In this experiment, four elimination reactions were compared and contrasted under acidic (H2SO4) and basic (KOC(CO3)3) conditions. Acid-catalyzed dehydration was done on 2-butanol and 1-butanol; a 2o and 1o alcohol, respectively. The base-induced dehydrobromination was performed on 2-bromobutane and 1-bromobutane isomeric halides. The stereochemistry and regiochemistry of the four reactions were analyzed by gas chromatography (GC) to determine product distribution (assuming that the amount of each product in the gas mixture is proportional to the area under its complementary GC peak).
In this experiment it includes testing water, using Silver Nitrate, waying out salt, and using lamps. When Starting before pouring your water test the water with silver nitrate to make sure it has not been contaminated.
The advantage of mini-cycle for the glucose metabolism will be less consuming time to produce glucose 6 phosphate because oxaloacetate can be produced rapidly from alpha-ketoglutarate. If there is deficiency of glucose 6 phosphates, the body can use mini-cycle to produce it by converting oxaloacetate (278). The disadvantage will always need enough oxygen to process this reaction because mini-cycle is aerobic metabolism (304). For the fatty acid metabolism, citrate can produce rapidly from alpha-ketoglutarate instead of using long general pathway of TCA cycle. When citrate is produced from oxaloacetate and acetyl-CoA in mitochondria, it will transfer to cytoplasm when beta-oxidation is suppressed. Then, citrate will convert into acetyl-CoA and oxaloacetate.
The ideal way to approach a question like this is through the means of a random experiment (students randomly selected). In this manner, the study would be subject to as few confounding variables as possible. Secondly, it would be optimal to control for unobservable characteristics such as ability bias and student perception in the study. In turn, this allows us to reduce the error term which could lead to a clearer possible causation as opposed to just correlation. Thirdly, the sample size should be as large as possible while being accompanied by an increase in the scope of comparison from two to four classes. Like in any other experiment, increasing the sample size yields better results that can be applied more universally. Fourthly, the experiment
Observations: There was a fizz that occurred in the test tube which means a gas was produced. Also the mixture became warmer, and when putting the lit piece of wood in the tube, the flame went out immediately making a noise, which means that there was no oxygen
In this lab, a metathesis reaction between an unknown metal carbonate (M2CO3) and calcium chloride (CaCl2), dependent on the ionic states of both compounds, allowed for identification of the metal through gravimetric analysis. Two grams of the metal carbonate were measured using an analytical balance and then dissolved in an aqueous solution with CaCl2 such that CaCo3 and a metal chloride formed from the reaction. The total mass of the metal carbonate was 112 grams per mole. Subtraction of the mass of CO3 from the total mass informed the metal’s identity: sodium. Due to the loss of precipitate and the utilization of two pieces of filter paper, a wide margin of error exists.
The purpose for this procedure is for students to familiarize themselves with how different types of properties can lead up to identifying substances. For the safety of this experiment be sure to always have your goggles on and tightly secured, due to any splattering of chemicals or glass breakage. Under no circumstance should any chemical be near your mouth. In this procedure students will use four methods that will help identify what is their unknown substance. Once all methods are done its data will provide physical properties of numerical values which students will compare to the list that will lead to identifying their pure substance. The four methods in this experiment are finding the density (g/mL), the solubility, the melting point
Atrazine is one the most widely used pesticide in the United States used for commercial farming. It’s purpose as a pesticide is to limit the weeds and unnecessary plants that would take nutrition from the crops that the farmers are trying to grow. Atrazine is supposedly known for increasing crop yield up to six percent according to a cost benefit analysis, but in other more in depth studies the only increase crop yield by one percent (Ackerman 1). Currently “the wet years as much as 7% or more of total Atrazine applied can be lost to surface water sources”, according to the prompt of the assignment. Meaning 7% of Atrazine goes into Americans water sources.