Unformatted text preview: CH 310M/318M (53195/53355) MWF 9:00 10:00 a.m. Dr. Brian M. Bocknack Spring 2010 End of Semester Information
Final Exam Day/Time: W ednesday, 5/12/2010, 7:00 to 10:00 p.m. Final Exam Location: Room assignments are based on the first letter(s) of your last name: Last name A Le report to WEL 1.308 to take the exam Last name Li-Sw report to WEL 1.316 to take the exam Last name Ta-Z report to WAG 420 to take the exam Assigned seating will be used during the exam. Seat assignments will be posted Monday, 5/10. PLEASE CHECK BLACKBOARD FOR YOUR SEAT ASSIGNMENT PRIOR TO THE EXAM!!! You must take the exam in your assigned room, and you must sit in your assigned seat! THE FINAL EXAM IS MANDATORY, AND MUST BE TAKEN AT THE TIME AND PLACE SCHEDULED BY THE UNIVERSITY REGISTRAR. NO MAKE-UP OR CONFLICT EXAM WILL BE OFFERED FOR THE FINAL. Office Hours: The regular schedule of office hours will remain in effect through Friday, May 7. Limited office hours will be held on Monday and Tuesday of exam week I Need Help!!! Blackboard for the updated office hours schedule. Office hours for the semester will end on Tuesday, May 11, so plan accordingly!!! TA discussion sessions have ended for the Spring 2010 semester. There will not be an organized review session for the final exam. General Exam Policies and Procedures: The exam will be closed book. No notes, books, calculators, or molecular models will be allowed. Scratch paper will be provided with the exam, as will a periodic table, a table of pKa values, and possibly other information that you may or may not find to be useful. The format of this exam will be similar to the midterms. The exam will be comprised of two distinct parts: o Part I will consist of a series of multiple choice questions. Your answers to these questions must You must use a #2 pencil to mark your answers on the bubble sheet! The answer sheet will be provided for you, b ut you will need to bring your own #2 pencil(s) to the exam. Bring several pencils with you to the exam we will not have extra pencils available for you to use! Only answers marked on the bubble sheet will be graded! You WILL NOT be turning in the part of the exam that contains the Part I questions, so there will be no way for us to grade answers that you mark on the exam form itself!!! Unless otherwise indicated, there will be one choice per question that is entirely correct, for which full credit w Part II will consist of questions for which you will need to write out your answers, using structures and/or words. This part of the exam will be handthe Part II questions, only blue or black ink is acceptable. Answers written in red ink will not be graded. Remember, scratch paper will be provided for you to work out your answers to the Part II questions. There will be no regrades possible for the final exam. Dr. Bocknack will check every final exam, and very carefully, before assigning final course letter o grades. Since you will not be able to submit your exam for a regrade, please feel free to use pencil when taking the exam. Please bring your valid UT ID card to the exam, since you will need to show it to the proctor when turning in your exam. Personal belongings (textbooks, notes, molecular models, food and WILL NOT be permitted at your seat during the exam you will be asked to place all personal belongings besides writing instruments and your photo ID in the aisles or at the front of the room before the exam begins. Please turn off cell phone ringers or any other device that might make a sound BEFORE the exam begins! The exam will start at 7:00 p.m. Students who are in their seats at the beginning of the exam will be provided with 3 hours to complete the exam. Students arriving late WILL NOT be provided with extra time to complete the exam. Students arriving after the first exam is turned in at any exam room WILL NOT be allowed to take the exam!!! When time is called at the end of the exam, all writing must stop immediately, and all exams and answer sheets must be turned in promptly. A student who does not stop writing immediately when time is called will not have his or her exam graded, and a grade of 0 DO NOT WAIT UNTIL THE LAST MINUTE TO FILL IN THE REQUIR ED INFORMATION AND ANSWERS ON YOUR SCANTRON BUBBLE SHEET!!! Bubble in your name, etc. as soon as you receive the answer sheet, and bubble in your answers as you work through the exam. Instances of academic dishonesty will be handled according to university policy, and will likely result in failure of the course. PLEASE DO NOT ASK PROCTORS TO INTERPRET QUESTIONS FOR YOU!!! The goal of the exam will be to test your understanding of the important concepts we have discussed thus far. Sufficient information will be provided in each question to make it clear exactly what is being asked. READ EVERY QUESTION VERY CAREFULLY!!! final exams. Specifically, students are expected to remain in the exam room until a test is completed. These policies will be strictly enforced, with no exceptions! You may not leave the room for any reason until you are ready to turn in your exam. If you wish to leave the room, you will need to turn in your exam to the proctors, and you will not be allowed to return. Plan accordingly by using the rest room before the exam starts. W hen you finish the exam, you will need to hand your Scantron form and your exam handout to a proctor, and show your ID. There is no makeup or conflict exam offered for the final! Specifically, failure to take the final exam at the scheduled time and place without an approved, documented excuse will automatically result in a failing grade being assigned for 310M/318M. A documented, excused absence at the final will result in an incomplete (symbol "X") being assigned for the course. An example of a documented, excused absence is a note from a doctor that states you are physically UNABLE to attend the final (a a doctor needs to state in writing that it is physically not possible for you to take the exam). Simply not feeling your best is NOT considered to be an excused absence, as we all have days in which we are not feeling well but must take care of our responsibilities anyway. If you are up and able to walk around campus on the day of the final, you must take the exam. NO EXCEPTIONS. The deadline to provide appropriate written documentation to receive an excused absence for the final exam is 5:00 p.m. on Friday, May 14. Students who receive an excused absence for the final exam will be required to take the final exam when it is administered to a regularly scheduled CH 310M/318M section at the end of the first Summer 2010 5-week session, or at the end of the Fall 2010 semester. IT WILL BE THE OTHER INSTRUCTOR Final Exam Coverage: The final exam will be comprehensive, and will cover all lecture material, related textbook material from suggested homework problems from the text). 2 The format of the exam will be similar to the midterms, but the exam will be slightly longer. The exam is worth 400 nts, and you will have 3 hours to complete the exam. Students who are well prepared should have absolutely no problem completing the exam in the time allowed. General Checklist of Review Topics: Refer to the review checklists posted prior to each midte rm exam for detailed listings of the topics you should remember from earlier in the course! material that you have not yet been tested on. Chapter 8: W hat reaction conditions are used for the radical halogenation of an alkane? Why is it necessary to shine light on the reaction mixture? to show movement of able to show all 3 stages of the mechanism: o Initiation radicals are formed; there is a net increase in the number of radicals o Propagation products are formed; no net change in the number of radicals o Termination any reaction in which radicals involved in chain propagation combine; net decrease in number of radicals W hy are more highly substituted C H bonds more reactive in both radical chlorination and radical bromination? W hat is the relative stability order for alkyl radicals, and what is the basis for this relative stability order? W hy is radical bromination more regioselective than radical chlorination? o Recall how we discussed the energetics of the rate -determining step of the mechanism, considered reaction energy diagrams for this step, and reached a conclusion based on In general radical chlorination will give mixtures of all possible substitution products. It is therefore not useful synthetically (unless only all C H bonds are equivalent, and only one substitution product is therefore possible). o Radical bromination will typically yield only the product in which the most highly substituted C H bond undergoes substitution. Because of this selectivity, this reaction is useful synthetically. W hat reaction conditions are used to achieve the allylic halogenation of an alkene? Understand the complete mechanism (initiation, propagation, termination) of this transformation. W hy is an allylic radical particularly stable? How does the regioselectivity of HBr addition to an alkene change if a peroxide is included in the o termination) of this transformation. You are not responsible for the material in Section 8.7 (autooxidation). Chapter 9: The SN stereoselectivity (stereochemical inversion is observed if the reaction takes place at a chiral center), how is reaction rate affected by the nucleophile, by branching on the electrophile, by the leaving group, by the solvent?] Some general issues that we discussed in the context of SN2: W hat makes a good nucleophile? W hat makes a good leaving group? Be able to classify a solvent as protic or aprotic, polar or nonpolar (you will be provided with dielectric constants if needed). The SN stereochemistry (why is racemization observed?), how is the reaction rate affected by the nucleophile, by branching on the electrophile, by the leaving group, by the solvent?] rate affected by the nucleophile, by branching on the electrophile, by the leaving group, by the 3 solvent?] Remember that SN1 and E1 involve a common carbocation intermediate, and therefore mixtures of SN1 and E1 products are typically obtained. Also remember to watch out for carbocation rearrangements!!! required?] Remember that the 4 mechanisms described in Chapter 9 all compete with one another!!! Given a description of the outcome of a reaction under a specific set of reaction conditions, you should be able to use your understanding of SN1/SN2/E1/E2 to explain the observed outcome. Given 2 reactions where only one variable has changed, you should be able to predict which reaction would be expected to be faster (or slower). You will only be asked to predict the outcome if conditions strongly favor one mechanism over the others. On the final exam, you will not encounter questions relating to the material in textbook Section 9.9 (neighboring group participation)!!! You will be expected to understand this material if you take Organic II, however. Chapter 10: Structure, nomenclature, and physical properties of alcohols. You were asked to read and understand this material from Sections 10.1 through 10.3. Deprotonation of alcohols to yield alkoxide ions. Understand why an alkali metal (Li, Na, or K) is the best reagent to use. Reactions of alcohols with HX. Result is a haloalkane. You should be able to use your understanding of SN1 and SN2 to determine the mechanism for a specific transformation. Remember to watch out for carbocation rearrangements!!! Reaction of 1° and 2° alcohols with PBr3. Overall transformation and reaction mechanism at the level it was discussed in lecture Reaction of 1° and 2° alcohols with SOCl2 in pyridine. Overall transformation and reaction mechanism at the level it was discussed in lecture. Reaction of alcohols with TsCl in pyridine. Overall transformation and mechanism at the level it was discussed in lecture. Why is the OTs group a good leaving group? Acid-catalyzed dehydration of alcohols. You should be able to use your understand ing of E1 and E2 to determine the reaction mechanism for a specific transformation. Again, watch out for carbocation rearrangements!!! In particular, understand how a carbocation rearrangement is the key step in the mechanism of the pinacol rearrangement (Section 10.7; you were instructed to read this! ). Oxidation of alcohols. Recognize the commonly used oxidizing agents. 1° alcohols yield carboxylic acids under aqueous conditions. Understand the mechanism as it was outlined in lecture. To stop at the aldehyde stage, use anhydrous PCC. 2° alcohols yield ketones upon oxidation 3° alcohols are inert to oxidation Also understand the oxidative cleavage of 1,2-diols using HIO4 (you were instructed to read about this!) On the final exam, you will not encounter questions relating to the material in textbook Section 10.9 (thiols)!!! You will be expected to understand this material if you take Organic II, however. Chapter 11: Structure, nomenclature, and physical properties of ethers. You were asked t o read and understand this material from Sections 11.1 through 11.3. You should also understand the material in Section 11.7, which deals with the nomenclature of epoxides. he course!!! W illiamson ether synthesis. Example of the SN2 reaction mechanism!!! Use of ROH instead of H2O in acid-catalyzed alkene hydration. Alkoxymercuration-reduction of alkenes Acidic cleavage of ethers by treatment with HX (X = Br or I). Be able to predict the products, and to determine whether the reaction occurs through an SN1 or an SN2 mechanism. Structure of epoxides. Why are epoxides considerably more reactive than acyclic ethers? 4 Preparation of epoxides by treatment of an alkene with a peracid (usually mCPBA). Understand the mechanism. Acidic cleavage of epoxides. Why does the nucleophile (H 2O or ROH) add to the more substituted epoxide carbon atom? Nucleophilic (basic) cleavage of epoxides. Why does the nucleophile add to the less substituted epoxide carbon atom? You will not be responsible for any of the material presented in textbook Sections 11.6 (silyl ethers as protecting groups), 11.11 (crown ethers), or 11.12 (thioethers)!!! Some Advice on Preparing for the Exam: At this stage of the game, it is unrealistic to think that you can go back to beginning of the course to learn everything from scratch. There is too much material, and only a limited amount of time. Since the final exam is the only opportunity to test your unders tanding of the material covered since Midterm Exam #3, you will be best served by spending your time making sure you understand this reaction mechanisms (SN1, SN2, E1, E2) from Chapter 9!!! Most of the reactions in Chapters 10 and 11 provide additional examples of these reaction mechanisms. time around. For example, if you lost a lot of points on Midterm #2 because you did not understand how to recognize stereochemical relationships (i.e. enantiomer, diastereomer, identical, etc.), you should probably spend some time reviewing this material. If you learn from your previous mistakes, you will not repeat them, and will be rewarded with a higher grade on the final! As usual, the best way to prepare for an organic chemistry exam is to practice working lots and lots of problems. Work through as many of the suggested homework problems from the textbook as l of these problems (or problems which are very similar) on the exam. Final Course Grades/Final Exam Retrieval: An announcement will be posted on the course web site when final grades have been uploaded to Blackboard. If this announcement has not been posted, it means that grades are not ready yet!!! Please do not send e-mail asking when grades will be available!!! My deadline to submit grades to the registrar is Monday, 5/17 @ 10:00 a.m. Most likely, grades during the day on Sunday 5/16. Once grades have been submitted to the registrar, instructions for picking up your graded exam at the Chemistry Lower Division Office (WEL 2.212) will be posted on Blackboard. Exams will be stored for one year. If you leave town before grades are ready, you can pick up your exam when you return to Austin for summer classes, or for the Fall 2010 semester . After one year, all exams that have not been picked up will be destroyed. Final grades will be calculated according to the formula outlined in the course syllabus: (0.35)(Final Exam T-score) + (0.275)(Highest Midterm T -score) + (0.275)(2 Highest Midterm T-score) + (0.10)(Final Homework Grade) = Final Numerical Average (T in the conversion table below)) A AB+ B BC+ C CD+ D
nd 5 DF o o o o T < 60.00 All of the grading elements used in the formula are based on a 100 point scale. determined by adding together your best 15 homework raw scores ( 600 points max.), and dividing this sum by 6 (to give a grade out of 100). Homework grades will not be curved. Your lowest midterm T-score will not be counted. Since a curve (T-score) was applied to each individual exam score, there will be no additional The grade boundaries stated above will not be changed, for any studen! Please note that grades in this course are based entirely on demonstrated performance on the o somewhere, and the unavoidable consequence is that some students end up just "a point" away from a higher grade. Everyone is graded according to the same standards , using exactly the same course grade, for any reason. higher grade to avoid academic probation, or to gain entrance to an honor society, or to avoid losing a scholarship, or because a higher grade will help you get into medical scho ol, or for any of the multitude of reasons not listed here WILL BE IGNORED!!! I will not even respond to the e-mail! Final grades assigned according to the scheme described in the course syllabus will indeed be final, and will not be adjusted for any reason. GOOD LUCK ON ALL OF YOUR EXAMS, AND IN ALL OF YOUR FUTURE ENDEAVORS!!! 6 ...
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- Spring '05
- Nucleophilic substitution, Chemical reaction, Organic reaction