CHEM 322L Organic Chemistry II Laboratory

CHEM 322L Organic Chemistry II LaboratoryName (Last First): ________________________Final Exam Fall 2015TA:_____________________________________12/03/15Take-Home: Due on or before 12/08/15 at 5:30 pm in SCB 213.ProblemPointsPart I (40)_____Part II (30)_____Part III (30)_____Total (100) _____ BONUS (10) _____ =____________________________________________________________________________________________Directions: 1. Make sure there are 9 numbered exam pages and 3 parts plus a BONUS question to thisfinal lab exam. 2. Print your name (last name first first name second) on this page of the exam only.3. Print the name of your teaching assistant (Alok or Datta). 4. Sign your name below acknowledgingthat you will honor the pledge. 4. Read each question carefully. Mark your answers concisely andlegibly and show all your work where required in order to receive partial credit; however write theanswer only in the space provided except where noted. This is a CLOSED book/notes exam. Youmay use the back of each page as scratch paper but it will not be graded. Calculators are allowed.Good luck!Pledge: On my honor I will not receive or give aid on this examination.__________________________________________________________________________________Kasey Kangaroo says “Have a safe and enjoyable holiday break. Best wishes for continued success atUMKC and beyond”.1 Part I. Experiment Specific Questions (40 pts)01. Multiple Experiments. You are extracting water-soluble impurities from your organic-solublecompound. Mark where the aqueous (A) and organic (O) layers would be for the following organicsolvents. (05 pts)EtherMethylene chloride?__________?__________?__________?__________02. Multiple Experiments. Shown below is an image of a sample lab notebook page (courtesy of A.Nerurkar) showing a chemical reaction and the table of reagents.From the data shown which compound is the limiting reagent in this reaction? Circle it on the imageitself. (05 pts)03. Diels-Alder Reaction. Reaction of Maleic Anhydride with Cyclopentadiene (Experiment 3). Thisexperiment affords the cycloadduct of the two reactants with a nearly exclusive preference for the endoisomer. Write the product of this reaction clearly showing the endo stereochemistry. (05 pts)O OO2 04. Epoxidation of Cholesterol (Experiment 2). You carried out the epoxidation of cholesterol using acommon perbenzoic acid namely MCPBA or m-chloroperbenzoic acid (see scheme below). Answerthe following question. (05 pts)MCPBAHCH2Cl240 °C 0.5 hHHOCholesterolMW = 386.66mp = 148-149 °CHHOHO5a 6a-epoxycholestan-3ß-olMW = 402.66mp = 110-112 °CSuppose you started with 200 mg of cholesterol and you produced 125 mg of the epoxide product.What was the percent yield of this reaction? Show your work.05. Acylation of Ferrocene (Experiment 5). In this experiment you used a technique called thin-layerchromatography (TLC) to monitor the course of the reaction as well as to locate the fractions obtainedfrom column chromatography during the purification phase. The following representation of a TLCplate shows the progress of a hypothetical organic chemical reaction. Answer the following questions.(05 pts)SRa. On the TLC diagram clearly identify the baseline (B) starting material lane (S) origin the productlane (reaction R)origin and the solvent front. (02 pts)3 b. Using the scale provided on the left of the plate calculate the Rf value for the starting material andfor each of the two products. (02 pts)c. By TLC did the reaction go to completion (Y/N)? (01 pt)__________06. Grignard Reactions (Experiment 1). You used a Grignard reaction for the synthesis of a tertiaryalcohol according to the following scheme:MgBr(excess)OOHetherBenzophenoneTriphenylmethanolThe yields for this reaction for this particular lab averaged only between 40-60%. However theGrignard reaction is typically a very high yielding process. Suggest some reasons (one main reasonreally) why this or any Grignard reaction for that matter might react in other ways so as tosubstantially lower the expected yield. (05 pts)07. Esterification – Synthesis of Banana Oil (Experiment 10). You prepared banana oil (isopentylacetate) by the acid-catalyzed Fischer esterification of acetic acid and isopentyl alcohol:OH H3COHHOOH3CO H 2OThis type of esterification is an equilibrium-driven process. Suggest four ways that the equilibrium canbe shifted to the right favoring the production of more banana oil. (08 pts)a.b.c.d.Of these which one(s) is (are) likely to be the most practical? (1 pt)Of these which one might be the most cost effective? (1 pt)4 Part II. Organic Laboratory Techniques (30 pts)Briefly describe the theory and proper execution of the following common organic chemistrytechniques. Make sure each of your responses address the following specific points: i) purpose of thetechnique; ii) theory behind the technique; iii) description of the technique in practice (e.g. how is itperformed).a. Recystallization. (15 pts)i.ii.iii.b. Thin-layer chromatography. (10 pts)i.ii.iii.c. Melting point (mp) determination. (05 pts)i.ii.iii.5