CHEM 2420 ---Organic Chemistry II Fall 2015 Mid-Exam]-18 (Form A)

CHEM 2420 --Organic Chemistry II Fall 2015 Mid-Exam No. 1: Chapters 12, 13 and 16 (Form A) Name: Instructions: A) Please print your name on the line above. B) Make sure you have 11 pages. C) Good luck! Question Score Multiple choice /80 Free response Bonus Total /20 /5 /105 1 [Page Section 1. Multiple Choice (80 points) Bubble the choice that best completes each phrase and/or answers the question on the Scantron sheet provided. Answers written in this section of the exam will NOT be graded (20 X 4 = 80 points). 1 .Which of the following compounds is the strongest base? a. CH3CH3 b. CH3CH2OMgBr c. CH3CH2OLi 3CH2Li 2. What is the major organic product obtained from the following sequence of reactions? Li Hexane CI H20 r a. 3-pentanol b. (E)-2-pentene c. (Z)-2-pentene )pentane 3. Which of the following alcohols can be prepared from a Grignard reagent and ethylene oxide? phÿ°H 1 ph.ÿ"ÿ°H .ÿÿT/°H 3 4 Ph t ethylene oxide a. only 1 only 1 and2 c. only 1, 2 and 3 d. 1, 2, 3 and 4 4. What is the major organic product obtaiÿlÿd from the following sequence of reactions? 21P a,,." e Br 1. Mg(O) PCC 22x,, 3, H30+ 0 1 o C. 3 d. 4 5. What is the major organic pro ained fro g reaction? 3 4 b. 2 C. 3 d. 4 6. What is the major organic product obtained from the following reaction? + Pd(PPh3)2CI2 NaOH f #JA4ÿ l 0 ÿ 3 IP a g e a. 1 d. 4 7, Which of the following is part of t ation stepÿor the monobromination of cyclohexane? I. ..2-Br: 0o oo 0o m, IV. + r Iÿ0 00 V. "Br: + "Br: m Br2 o,P €o d) IV e) V r oÿf dej]e] ................................... ""i;fl" 8, Rank the free radicals (I-III) shown below in or sing stability (i. om stable). .'-ÿ ....... ÿ • CH2CH2CH(CH3)2 I I ÿ most stable to least o CH3CH2C(CH3)2 II ÿ CH3CHCH(CH3)2 III 2- c) I II III d) II I III e) III II I u/ 41Page 9. What is the ÿ product of the following reaction? cÿ I-tBr ? Peroxide Bt" I, CH3 IV, Vl ..,CK3 II° Br -Br a) I e) V 10. How many distinct monochlorinated products, including stereoisomers, can result when the alkane below is heated in the presence of C12? c) 3 D) 4 E) 6 51Paoeÿ, 11. When (R)-2-bromobutane reacts with C12/hv, which of the following is true? CH3 B r-- --H C l-- --H CH3 I CH3 Br-- --H H-- --Cl CH3 II A) Only I is formed, B) Only II is formed. If ...... CÿI and II are formed in equal amounts, jJJ .... Dÿ and II are formed in unequal amounts. "E) I and II could never form under these conditions. 12. What reagent can best be used to convert cyclopentene to 3-bromocyclopentene in a single step? C) HBr D) HBr with peroxide 13. What is the IUPAC name of the following compound O Z. Qf a. 3,3-dimethylhexanoic acidÿ hylpentanom acid c. 2,2-dimethylpentanal d. 4,4-dimethyl-6-hexanoyl acid 14. Which of the following compoundÿ is an acyl chloride? ut 6 [P a g e ,el V, c1 C) III D) IV E) V 15. Give the name of the structure. OII CHÿCH2 CH:-/C"ÿ" 0- r,,lH.t+ A) amino projÿanoate ammonium butanoate C) amino butanoate D) ammonium propanoate E) propyl amine 16. What is the hybridization and geometry of the carbonyl carbon in carboxylic amides? A) sp3, tetrahedral 0nal plan C) spZ, teÿ D) sp3, trigonal planar E) sp, trigonal planar 17. Which of the following compounds is most reactive toward nucleophilic acyl substitution? 71Page A) OII R--C--NH2 B) oII ) , © O II II R--C-O--C--R E) ©JJ R--C--OH 18. Which of the following is (are) formed in the reaction between methyl butanoate and propylamine? A) methanol B) 1-butanol C)ÿ-pmpÿbutanamide E) both B and C O 19. What is the ma__m_ajÿ organic product of the following reaction? /ÿ/CO OH H@ LOÿ + HOCH2CH2OH ÿ ? J 8[Paÿ.e I, iÿ.....CH2 C H2"-.. (ÿ.. HoociV ÿLCOOH O O II II ./CO CH2C H20 C'--. IH V, A) i B) n E) V 20. Which of the following compounds is hydrolÿp,ÿ,, ÿ-ost slow aqueous NaOH? J A) O O R--$--M)--ÿ--Ct-I3 O D) O R--ÿ--OCH3 E) o R--ÿ--CI J aÿ 9 IP aÿ,, e Section 2. Free Response (20 points) Write CLEARLY in complete sentences or show all work if the problem calls for it. Remember to show all lone pair electrons if drawing a mechanism. . Mechanism. Draw the mechanism by which the following reaction occurs. Be sure to show curved arrows to indicate the movement of electrons as well as all lone pair electrons. (2 × 6 = 12 points) a. heat + Br--Brv,---- + HBr Please show initiation, propargation, and termination steps gÿ bo H® v H20 0 + HOÿ lOIPaoe,:ÿ 2. Synthesis. Provide all reactants, reagents, and intermediate products for preparation of the following product from starting material (8 points). CH2CH3 CH2CH2CÿN cM ÿ Bonus (5 points): Provide the other four resonance structures of the following benzylic radical. .Sÿ' ,..,IF._.) ÿs llIPage