Sample_Exam_2_Key-1 - CEM251/Fall 2009/Se'cond Hourly Exam...

Info iconThis preview shows pages 1–7. 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
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: CEM251/Fall 2009/Se'cond Hourly Exam ..... ..(page 1) w l l "l . I | (20 points total) at:- . I" r. 1. Draw the structure of the following compounds: 8) . 2 pts. 2—methyI-2-pentanol b) t—butyl alcohol C) 4-bromocyclohexanol d) 2-methoxy-2—methylbutane 2 pts. 6‘) ethyl isopropyl ether 2 pts. f) ' 2,2-dimethyloxlrane Q) ' isobutylene 2 pts. h) (E)-2—bromo-3-methyl-2-pentene 2 pts_ i) (Z)-3,4-dimethyl-37hexene _ 2 pts. l) 3-phenyI-1-butyne . _ CEM251/Fall 2009/Se'cond Hourly Exam.......(page 2) (12 points total) ' 2. @A/ m A ,5 s a) Which of the above carbocations (A, E, E) is a secondary (2°) carbocation? -b)- Which is the most stable carbocation?- C) Which one is the least stable carbocation? 3. a) Which of the above halides (25, 1,5) reacts fastest by an 8N2 mechanism? b) Which of the above halides (25, 1,5) reacts fastest by an 8N1 mechanism? c) Which gives the lowest yield of I substitution product when reacted with NaCECH ? CEM251/Fall 2009/Second Hourly Exam ..... ..(page 3) (16 points total) ' 4. Draw struotures in the boxes to complete the following reactions. Show stereochemistry in all cases: ' ' a ) CH3 NaOCHZCH3 —-. (3N2) b) OH CH}; H C) C s B 2pts. \\ r A _ KOH (E2) CH3 CH3 H d)_ C 3 Br 2pts. A _ KOH (E2) CH3 CH3 9) CH3 2 pts. \Br A “a; I ——h'- 2 H20 at .2 (5H (E1) _—-" / \ f.»- \fi CEM251/Fail 2009/Second Hourly Exam ..... ..(page 4) (12 points total)-_ 5. Draw the structure of the major organic product: Br CH3 i i A CH3CH2 Cl—CIJH KOH CH3 CH3 2 pts. A . CHSOCH20H20H3 ——> HBr (excess) / \ /CH3 CH30H CH2 C\ H2804 d) 2 pts. 2 pts. HO CH3 H2804 major elimination product CEM251/Fall 2009/Second Hourly Exam ..... ..(page 5) (8 points total) ' - 6. Carbocation X rearranges to a more stable carbocation Y. Draw the structure of Y and the major elimination product formed from it. (2 pts.) CH3 I (+) ——-——-—,- CH3 (2 pts) Major elimination product 7. The following carbocatlon (A) is formed in pure methanol solution. Draw the structure of the two substitution products (configurational isomers) formed when A reacts with the solvent. CH3 CH30H —h— - CEM25‘I/Fall 2_009/Second Hourly Exam ..... ..(page 6) (20 points total) 8‘ Draw the structure of the major organic product: 2 pts. Br I A CHgCHg CH . l NaNH2 Br (excess) b) d) Br (3143(3H2<3H=c3H2 —2—> f) Cl CHSCHZCECH —2> - (excess) enol intermediate I CEM251/Fall 2009/Second Hourly Exam ..... ..(page 7) (12 points total) 9. Draw structures in the boxes to complete the following reactions: 8) 2 pts. CH3 HBr —> 2 pts. carbocation intermediate b) 2 pts. G" "L bromonium ion intermediate, organic product, X“ ‘I L1 t! r ' , "a! show stereochemistry 9' show stereochemistry y, 1 . I .-- ' 10. (4 pts.) Synthesize the following compound from acetylene. You may use any additional reagents desired. _ Make: CH3CEC—CH2© From: HCECH “Cr-61"..“1W (1qu C535 H. '. '2. at}, “T: 5 ...
View Full Document

Page1 / 7

Sample_Exam_2_Key-1 - CEM251/Fall 2009/Se'cond Hourly Exam...

This preview shows document pages 1 - 7. Sign up to view the full document.

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