Chem 308_Summer 2010_Exam I Key

Chem 308_Summer 2010_Exam I Key - Exam 1 new Chemistry 308...

Info iconThis preview shows pages 1–9. 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 Document Right 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 Document Right 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 Document Right 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 Document Right Arrow Icon
Background image of page 8
Background image of page 9
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Exam 1 July 22, 2010 new! Chemistry 308 113/114 .Student'Name (PRINT CLEARLY): Student Signature: Section Number (H3 before lecture, H4 after lecture): SEAT NUMBER: Instructions PRINT YOUR NAME AND SECTION NUMBER AT THE TOP. Please fill out A__L_L_ of the information requested at the top of this sheet. This exam consists of 10 multiple—choice questions and 10 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 within this exam booklet only. At the end of the exam, you must hand in this complete exam booklet. Do not separate any_of 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. The product of a Diels~Alder reaction is showrr below. Draw the structures of the two organic I compounds used in this reaction (3 points)? / UV r ON ./ Ar )( r, #4....» \ N C (as) ' . Km 0W) 2. Draw all the important resonance structures of nitrobenzene in the space below (3 points). c . (D \ GB Q9 4. 'Ga 0 \Q (03 0 \® 5 D Q ' ~ 0 - \ / N 3. Draw the four most important resonance forms for the organic intermediate in the reaction shown below. Indicate all formal charges clearly (3 points). ‘ OCH8 . OCHS G ‘ BIZ i .Br. ® @093 O C“ 3 0mg 0 m? gf /\*\/gr ' A E” J gr KS flak/J“ D3 U“ 6‘5 U Total points this page (max 9) : rm the synthetic transformation shown below. Number the d give the products of each reaction (3 points)? 0 4. Give the reagents necessary to perfo reagents for separate reactions, as usual, an fl Uh (DEX) AKU‘Vg OZN 1,. Flu ) H19 "a. Hrmzlhém , . . \|\\’ Ego/$0“? 7‘3.) ,. K ~ , Q \ ' (r M1 - L 5. In the box provided, draw the structure of the organic hydrocarbon with the molecular formula C10H14'that corresponds to the IR and NMR spectra on the next page of the exam (3 points). 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). Br (’3 Total points this page (max 9) : 19 MICRDNS 2.3 0 Flillu .A B 3. D 0 5 0 IIIIFl-L wcnfiAmce 600 1300 2000 2.4 25 25 2.72.819 3 00 4400 4200 4000 3800 3500 3 3400 3200 3000 2500 2500 2400 2200 NICOLE? 205x FTle WAVENUMEEBS 20 40 ab 80 DO 1 120 (DE-300 140 160 180 CDCI3 DO 2 l 7. Give the major organic product expected for the synthetic transformation Shown below (3 points). o‘A 1; CH3COCl, A1C13 2. HCl, H20 workup 3. CH3CH2MgC1 4. HCl, H20 workup 8. Draw the structures of the compounds named below (3 points). Benzoic acid: . C 01% Phenol: Q“ Toluene: 3 U o / HNO3, H2804, 300 °_C \N (I k\\ y ‘ N 10. Give the reagents necessary to perform the synthetic transformation shown below in good yield: Number the reagents for separate reactions, as usual, and draw the structures of the products of each reaction (3 points). ? (2’4- Q OH \. Ar H 0 WRQM‘XLWX at. Total points this page (max 12) : 11. What is the major organic product expected from the synthetic transformation shown below (2 points). 12. Which compound will undergo a dehydration reaction at the fastest rate when heated with , concentrated sulfuric acid (2 points)? A B c MOI-1 M: Total points this page (max 4) : 13. Using a Frost's Circle analysis, how many bonding, non—bonding and anti—bonding at—molecular orbitals are there in the structure of the cyclopentadienyl anion (2 points)? @ 3 bonding; O non~bonding; 2 anti—bonding B 1 bonding; 2 non—bonding; 2 anti~bonding t C 4bonding; O non—bonding; l anti—bonding D 2 bonding; 2 non-bonding; l anti—bonding E 2 bonding; 1 non—bonding; 2 anti—bonding 14. Which combination of p—orbital diagrams correctly shows the frontier orbitals involved in the Diels Alder reaction below (2 points)? CN DN+Y EM+X A L+Y 15. Which one of the monobrominated compounds below is not expected as a major product of the NBS reaction shown (2 points). NBS, ROOR _..—_—————————-———————-——-————V7 ? 3o 8er YES, $5 A (t) I E Total points this page (max 6) r: ‘ (3 e Which compound cannot be synthesized in good yield by Friedel—Crafts alkylation of benzene (2 points)? f n, - WW? é <§ ‘" Which structure is consistent with the 1H— and 13C—NMR spectra shown below. Circle your answer (2 points). com3 05-300 120 ’100 80 60 40 20 0 240 220 200 180 1 60 1 40 $2 11 Total points this page (max 4) : 18. Which p~orbital diagram best represents the hi ghest-energy occupied molecular orbital (HOMO) of 1,3,5—hexatriene. Circle your answer (2 points). 19. Which gig ion is aromatic? Circle your answer (2 points). (9 CI 9 (5) ‘ AG) 0 Q . Q HN\::/NH A B . (3 ® E 20. Which statement is NOT correct regarding the UV spectra of compounds containing 31; bonds? A The molar absorptivity of a polyene at its kmax increases as the number of conjugated at bonds increases. ® The Kmax of the HOMO—LUMO ar-to—n* transition is lower for 1,3,5~heXatriene than it is for 1,3— butadiene. ' C Absorbance (A) at any wavelength is proportional to the concentration of the UVaabsorbing compound in the sample solution. D The longest wavelength absorbance peak in the UV spectrum of a fully conjugated polyene is due to the HOMO-LUMO VINE-313* transition. E An absorbanCe (A) of 2.0 corresponds to a % Transmittance (%T) of 1%. Total points this page (max 6) : ...
View Full Document

{[ snackBarMessage ]}

Page1 / 9

Chem 308_Summer 2010_Exam I Key - Exam 1 new Chemistry 308...

This preview shows document pages 1 - 9. Sign up to view the full document.

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