University:
Kentucky State University
Course:
CHE 302 | Organic Chemistry II
Academic year:

2024
Views:

347

Pages:

5
Author:

Quintin Ware

Organic Chemistry EXAM Second -4 Solved by: Corrected by: - Chemistry Department Organic Chemistry Midterm(60 min.) Name:…………xxxxxxxxxxxxxxx……………..……Registration No.:……………   I. Circle the correct answer in each of the following: (10 pts)  The number of stereogenic centers in the molecule below is: OH CH3 N NH2 a. 1 H b. 2 c. 3 d. 4 e. 5 d. 4 e. 5  The number of possible stereoisomers of: HO2C CH2 CH CH Cl a. 1 b. 2 CH2 CO2H Cl c. 3  The observed  rotation for 100 mL of an aqueous solution of 1.0 g of sucrose in 20 cm sample tube is +1.33. The specific rotation [] is: a. +66.5 o b. +26 o c. +41.5 o d. +133 o e. -26 o  Which of the following molecules are the same: H CH3 Cl CH3CH2 CH2CH3 1 a. 1 and 2 CH3 Cl CH2CH3 Cl H H CH3 Cl CH CH 2 3 4 b. 3 and 4 H3C H 3C 2 c. 1 and 3 d. 2 and 3 3 e. 2 and 4  Which of the following is the strongest acid: OH OH OH OH OH NO2 NO2 a. b. c. e. d. CH3 NO2  Which of the compounds listed below would you expect to have the highest boiling point? b. a. d. Cl e. OH O 1 c. O  Which of the following is the best method to prepare isopropyl methyl ether: a. CH3OH + (CH3)2CHOH + H2SO4, 140 oC b. CH3OH + (CH3)2CHCH2OH + H2SO4, 140 oC c. CH3ONa + (CH3)2CHBr d. CH3ONa + (CH3)2CHCH2Br e. CH3I + (CH3)2CHONa  Which of the following synthetic methods of alkyl halide is expected to occur at fastest rate? OH + OH HBr OH + HI + HCl a. b. c. OH OH + HI d. e. + HBr  Which one of the following is the strongest nucleophile: a. CH3O Na in CH3OH b. NaOH in H2O d. NaCN in H2O e. CH3OH in H2O c. NaCN in Acetone  Which of the following reactions proceeds with inversion of configuration at the carbon bearing the leaving group? a) SN2 b) SN1 c) E2 d) E1 e) All of them II. Given the following alkyl halides:(4 points) CH3 Br H3C H A CH2Br Br Br H3C H H B C D 1. The most reactive alkyl halide with NaOCH3………………C………. 2. The compound that produces a pair of diastereomers when reacted with CH3OH…D 3. The least reactive alkyl halide towards nucleophilic substitution………A………… 4. Draw the structure of the major product obtained when heating C with NaOH An E2 reaction happens and the product is: 2 III. Give the correct IUPAC names for each of the following compounds:(4 poins) H3C Cl C CH2CH(CH3)2 C Br 2-bromo-3-chloro-5-methyl-2-hexen OH O 5-ethoxy-3-pentanol IV. The configuration of the indicated stereogenic center is:(2 points) OH H CH2NH 2 R (rectus) V. Label the following pairs of isomers as enantiomers, diastereomers, conformational, constitutional or identical :(8 points) CH2OH H HO H HO CH2OH HO H HO CH3 Enantiomers CH3 Enantiomers CH3 H H CO2H HO H CH3 HO HO2C CO2H HO2C HO2C Br CO2H Constituationals Br Conformationals Br Br 3 VI. Complete the following reactions giving the major products:(22 points) CH2Br + NaCN CH3 DMSO CH3 H H CH2CN Br CH3SH CH3 CH3O Na / heat H3C C CH3 I H H SCH3 CH3-C=CH2 + NaI CH3 O HO H CrO3 Br PBr3 H O-Na+ OH NaH NR NaOH OH K2Cr2O7 OH OH H2SO4 / heat CH3 O =CH2 + minor major HI + heat 4 ICH(CH3)2