Problem Set 7 in Chem 220a: Alkene Reactions and Diagnosis, Assignments of Organic Chemistry

Download Problem Set 7 in Chem 220a: Alkene Reactions and Diagnosis and more Assignments Organic Chemistry in PDF only on Docsity! Chem 220a Problem Set 7 Chapter 8 Due: Monday, October 31, 2005 Reading Assignments The alkene module in ORGO. Ozonolysis module. How do I approach solving problems like #1-5? These problems require factual knowledge and an ability to reason. Pretend you are a doctor and patient has certain symptoms (the facts presented) and you must call upon your knowledge to provide a diagnosis (solution). Here is a step-by- step analysis (diagnosis) of #2 PS7 from F2000. I recommend that you do question 6 first. it will give you some background. Vladimir Vasilovich Markovnikov (1838-1904) 1. Alkene A reacts with chlorine to form meso B. Ozonolysis of A forms a single compound C. Hydrogenation of A liberates 27.3 kcal/mol of heat to form a normal chain alkane D with an estimated ΔHfo of -59.8 kcal/mol. What are the structures A-D? Explain and illustrate. 2. Compound A is optically active and it absorbs two equivalents of H2 to form optically active B (C10H20). Treatment of A with warm, concentrated KMnO4 forms (R)-2- methylsuccinic acid (tartaric acid = 2,3-dihydroxysuccinic acid). What are the structures of A and B? Explain and illustrate. 3. Hydroboration-peroxide oxidation is said to be an anti-Markovnikov addition of water to an unsymmetrically substituted double bond. Yet, hydroboration of an unsymmetrically substituted double bond is a Markovnikov addition of borane. Explain and illustrate. 4. Hydroboration of (Z,Z)-1,4-cyclooctadiene at room temperature gives two boranes, A and B, both with the formula C8H15B. Alkaline peroxide oxidation of A gives a 1,4- cycloctane diol (di-alcohol) while B gives the 1,5-isomer. When a mixture of A and B, or either one of them on their own, is heated, cooled and oxidized, B dominates over A. a) What is the stereochemistry of each diol? b) Explain and illustrate the conditions under which A and B are formed vs. B alone. A reaction co-ordinate diagram would be helpful.