Abstract Otto Diels, Professor of Chemistry at the University of Kiel, Germany, and his student Kurt Alder published a paper in 1928 on additions of electron-poor alkenes and alkynes to electron-rich dienes to form cyclohexenes and cyclohexadienes. These [4+2] cycloadditions came to be known as Diels-Alder reactions. The Diels-Alder reaction is one of the most useful synthetic reactions in organic chemistry. In one step the reaction forms a six-membered ring with one or two double bonds forming an open-chain compound. A diene is the 4-pi-electron component.
McGraw-Hill companies, Inc.) Although sulfuric acid served as the acid in the reaction, it is also the catalyst in the over-all reaction. Water, attached to N, is good leaving group so it is eliminated to form the nitronium ion. The ppt was further recrystallized and purified. It was first dissolved in hot dH2O and then hot gravity filtration was performed. Many insoluble substances were isolated and cream in color.
EXPERIMENT 2 Title : GRIGNARD REAGENT -TRIPENYLCARBINOL Objective : To prepare triphenylcarbinol through a Grignard reaction by reacting methylbenzoate with phenylmagnesium bromide Introduction : The chemical reaction between an organic halide and a magnesium metal can produce an alkyl or aryl free radical and magnesium free radical. The formation of Grignard reagent has been occurs. The bonding between carbon and magnesium is a covalent bond but it is highly polarized because the magnesium is bonded to halide which is an electron withdrawing group. This causes the formation of partial positively charge and partial negatively charge on the magnesium atom and alkyl or aryl group respectively. Hence, the carbanion has both characteristics of a good nucleophile and a strong base.
2. Acetylation of p-methylaniline to create p-methylacetanilide. Here acetic anhydride will be used to prepare the nitrogen substituted acetamide. This is conducted to make the amine group, which is a very stong ortho and para directing activator on an aromatic ring, a lesser strength activator so that the oxidation of the methyl group can proceed. 3.
Software maintenance This type of maintenance is important as it will allow you to protect the computer and also the documents that it contains. To ensure that your computer is virus free then you will need to download an anti-virus program in order to clean up the computer from any harmful viruses that it may contain or may be left inside of downloaded files. I have installed an anti-virus program and I will now show you how to use it. 1. First you will need to enter ‘my computer’ 2.
The Fajan method is named after American physical chemist Kazimierz Fajans and a dichloroflourescein indicator is used to indicate the equivalence point. The equivalence point in noted when the solution changes to a pink colour. The Mohr method is named after German chemist after Karl Friedrich Mohr and uses potassium chromate (K2CrO4). The colour of the solution at the equivalence point changes to a brownish red colour2. The following reaction has taken place to completion by the equivalence point: 2Ag+ (aq) + CrO42- (aq) → Ag2CrO4 (s)2 The second technique used in the experiment is the gravimetric technique.
Synthesis of the Diels-Alder Adduct Purpose: To investigate the methods behind Diels-Alder chemistry through the synthesis of 4-cyclohexene-cis- 1,2-dicarboxylic anhydride from butadiene sulfone and maleic anhydride. By using a hands-on approach through laboratory synthesis, I hope to gain a better understanding of the concepts governing Diels-Alder reactions. Theory: The Diels-Alder reaction is a cycloaddition reaction that occurs between a conjugated diene, a molecule with two alternating double bonds, and dienophile, an alkene, to form rings and bicyclic compounds. Because it involves the interaction of four π electrons that are supplied by the diene and the two π electrons supplied by the dienophile, the Diels-Alder reaction is often called [4 + 2] cycloaddition. In the reaction, two new σ bonds are formed and one π bond is formed at the expense of two π bonds, which results in a cyclic product.
8th Magnesium 12/5/11 Objectives: 1. Show the reactivity of Group 1A metals with water to produce hydrogen gas. 2. Demonstrate the dangerous dehydrogenation capability of sulfuric acid. Discussion: A and B are the elements while BC and AC are compounds.
This is a neutralization reaction between a strong acid and strong base. Therefore the heat of reaction (∆H2) is called as the heat of neutralization of HCl and NaOH solutions. The ∆H2 calculated from this experiment is -6.6944KJ/mol. This is because the enthalpy changes when one mole of H+ ions from an acid (HCl) reacts with one mole of OH- from an alkali (NaOH) to form one mole of water molecules under the stated conditions of the experiment. In the final reaction of the experiment (Part C), solid NaOH will react with an aqueous solution of HCl.
An alternate name for Complex Q is Ubiquinone. The importance of CoQ is that not only does it accept electrons from NADH dehydrogenase complex (A.K.A Complex 1) but it can also accept electrons from Complex 2 (A.K.A succinate dehydrogenase). Succinate is one of the intermediate products in the citric acid cycle. Succinate dehydrogenase acts on succinate to create fumarate in the citric acid cycle. In the