Chem 308_Summer 2010_Exam 1v

Chem 308_Summer 2010_Exam 1v - Chemistry 308 V1/V2 Exam 1...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 8
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Chemistry 308 V1/V2 Exam 1 June 18, 2009 Student Name (PRINT CLEARLY): Student Signature: Section Number (V1 before lecture, V2 after lecture): SEAT NUMBER: Instructions i PRINT YOUR NAB/[E AND SECTION NUMBER AT THE TOP. You may not get a copy of your exam if the pages are missing your section number._ ‘ Please fill out ALL; of the information requested at the top of this sheet. This exam consists of 5 multiple—choice questions and 15 questions requiring written responses. To answer a multiple~choice question, circle the letter corresponding to your answer. Questions requiring a written response should be answered clearly and legibly and only in the space provided. Please answer all questions withinthi's exam booklet only. At the end of the exam, you must hand in this complete exam booklet. Do not separate anygf the sheets in this booklet or remove the staple. Do not hand answers in on extra sheets. The length of the exam, including time allowed to fill in all responses, is 70 min. Exam Form Number: 1 1. Draw the structure of the major organic product of the reaction sequence shown below (3 points)? 1. lithium diisopropyl amide (LDA) _._____._......_._——-——-——————————>- ? /\/\B,,- 2, F2Q=CF2 , heat 2. Draw the structure of meta—chlorotoluene in the space below (2 points). 3. Draw the three most important resonance forms for the organic intermediate in the reaction shown , below. Indicate all formal charges clearly (3 points). W~ Br Total points this page (max 8) = 4. .Give the reagents necessary to perform the synthetic transformation shown below. Number the reagents for separate reactions, as usual (3 points)? ‘ 5. Draw a p—orbital diagram representing the frontier orbital (HOMO) of 1,3—butadiene in the reaction shown below (2 points). ' ~ ' / phOtolysis (hv) ANSWER: ‘ \ ' 6. Write a detailed mechanism for the reaction shown below. Use arrows to represent all electron movements, show all intermediates, and indicate all formal charges clearly (3 points). NLBr AAOA CH3CHZOH Total points this page (max 8) :2 7. Give the major organic product expected for the synthetic transformation shown below (3 points). 1. NBS, hv Q 2. Mg, THF ‘ - ' '2 3. CH3CHO ' 4. aqueous HCl to neutralize 8. Write the common name for the compound shown below (2 points). NH2 9. Give the reagents necessary to perform the synthetic transformation shown below. Number the reagents for separate reactions, as usual (3 points). CI sogH Total points this page (max 8) = 10. The IR spectrum of an aromatic hydrocarbon is shown below. Use arrows to indicate the most important absorbance peaks that identify the presence of a benzene ring in this compound. Label these arrows peaks according to the type of vibration they indicate (for example: spSC-H stretch; C=O stretch; or C—C bend) (3 points). as: -. .4500 4400 ‘200 4000 3500 3600 3400 3200 3000 2800 2500 2‘00 2200 2000 1800 £1000 . 1400 1200 4 1000 800 600 WAVENUMBERS NICOLET 205x FT-IR 11. Draw the structure of the major organic product of the reaction below (2 points). H C . V 3 ' Brz, Fe __..__——————,————-———-—-————-—> ? no2 12. Draw the structure of the electrophile in the reaction shown in the previous question (2 points). Total points this page (max 7) = . 13. How many bonding, non—bonding and antibonding :nz—molecular orbitals are there in the molecular ' structure of cyclobutadiene (3 points)? V Number of bonding orbitals : . _ Number of non—bonding orbitals = ' 0 Number of antibonding orbitals : ‘ cyclobutadiene 14. Draw the structure of the major organic product that is formed under thermodynamic control of the reaction shown (3 points). » BIZ 15. Write a detailed reaction mechanism showing how the electrophile is generated in the reaction shown below. Use curved arrows to Show all electron movements and indicate all formal charges clearly (3 points). ‘ ' O HNO3, sto4 . N02 _..—--—-——-——-—————-—> Total points this page (max 9) : 1 16. If the UV—VIS absorbance spectrum of any compound is measured, the wayelength of the lowest~ energy absorbance peak, 7», may be used to calculate the energy difference, AB, between the HOMO and LUMO orbitals of that compound. Which eXpression will give this energy difference? Circle the answer (2 points). (Note that h : Plank’ s constant, e 2: molar absorptivity, C = speed of light, A = absorbance) A AB .—= A/s?» B AB = 2A0» c AB = C/e)» D AB = hC/l» ‘E AB 2 MM; 17. Which structure is consistent with the ‘I-L and 13C—NMR spectra shown below. Circle your answer (2 points). ' ' Total points this page (max 4) = 18. Which compound will give the. most gara—brominated product in a reaction with bromine and ferric bromide? Circle your answer (2 points). . r o y _ SOgH _ 0A0 G 3 A' B . 'C D E 19. Which one compound or ion is aromatic? Circle your answer (2 points). /\@ 6] [:1 Q © . A B C 20. Which sequence of reactions is the best choice for performing the synthetic transformation shoWn? Circle your answer (2 points). 0 I ? ‘ V NH2 . . A 1. CHSCHZCI, A1C13, heat; 2. HNOS, H2804; 3. H2,Pd~C B 1. H2,Pd~C; 2. CH3C0C1,A1C13, heat; 3. Hszo 4.1—1N03,sto4 C i. CH3C0C1,A1C13, heat; 2.1311420; 3. H2,Pd~C; 4.NaNH2 D 1, CH3COC1,A1C13, heat; 2. H",HZO; 3.HNO3,HZSO4; 4. H2,Pd—C E 1. mo3,sto4; 2. CHSCOCI, A1C13, heat; 3. H+,'Hzo; 4. H2,Pd~C ‘ Total points this page (max 6) = ...
View Full Document

Page1 / 8

Chem 308_Summer 2010_Exam 1v - Chemistry 308 V1/V2 Exam 1...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online