Chem 341, Quiz #9B 20 points total Your score:_____of 20. Date: 11/9 Name (Last, First): ________________________________________P # : _______________ Please, write and draw in legible manner. The answer the grader cannot read/understand will be considered wrong! All questions that are A/B/C/D must be answered A/B/C/D. If you leave the window for an answer empty, it means you did not answer. If you think that none of the suggested answers is correct, write “none” in the answer box. Your answer 1. Which of the following compounds 1-4 is not chiral? Cl F CO2H HO2C Cl F3 C Ph Cl 2 1 A) 3; 2. B) 4 ; C) 2 ; OH Cl CF3 F CHO HO2C Ph 3 C OH 4 D) 1 Which of the following compounds is a meso-form? 1 2 3 4 5 CF3 F CF3 CF3 CF3 CF3 CF3 F3 C CF3 CF3 CF3 CF3 F3 C CF3 A CF3 F3 C CF3 CF3 A) only 4 B) only 5 C) only 1; D) only 1 and 5 3. Which of the following is correct Fischer projections of the compound on the left? 1 Cl CH=O CH=O H CH3 H Cl 2 CH=O 3 CH=O 4 H3C H H CH3 Cl H Cl H Cl H H CH=O A) 3; B) 4 ; C) 2 ; D) 1 4. C What is (are) the major organic product(s) obtained from the following reaction? C 1 (2R,3R)-dichlorobutane 2 (2S,3S)-dichlorobutane 3 meso-2,3-dichlorobutane A) only 2; B) only 1; C) only 1 and 2; D) only 3 5. Which of the following structures represent the same stereoisomer? D A) only 1 and 2; B) 1, 2 and 3; C) only 1 and 3; D) only 2 and 3 CHEM341 Quiz #9, page 1 6. What is (are) the major organic product(s) obtained from the following reaction? D 1 (2R,3R)-3-bromo-2-butanol 2 (2R,3S)-3-bromo-2-butanol 3 (2S,3R)-3-bromo-2-butanol 4 (2S,3S)-3-bromo-2-butanol A) 1, 2, 3 and 4; B) only 2 and 3; C) only 1 and 2; D) only 1 and 4 7. What is (are) the major organic product(s) obtained from the following reaction? B 1 (2R,3R)-dibromobutane 2 (2S,3S)-dibromobutane 3 meso-2,3-dibromobutane A) only 2; B) only 3; C) only 1; D) only 1 and 2 8. Which of the following compounds 1-4 are enantiomers? F 1 CF3 CF3 2 CF3 H F H Et CH2CF3 CH3 4 3 CF3 H H F3C H H F H H CH2CF3 H Et H F CH3 H H H CF3 H F H H B CF3 CF3 A) only 2; B) only 3; C) only 1; D) only 1 and 2 9. Which of the following compounds is a meso compound? A) (2R,3R)-3-bromo-2-butanol B) (2R,3S)-3-bromo-2-butanol C) (2R,3S)-difluorobutane D) (2R,3R)-difluorobutane 10 C Which of the following is the definition of a meso compound? A) A diastereomer with two chirality centers that has a plane of symmetry B) A molecule with two identical chirality centers C) A chiral compound with more than one chirality center D) A molecule with chirality centers which is not achiral 11 A Which of the following structures is not chiral? 1 3 2 F 4 CF3 F F3C A) 3; B) 1 ; C) 4 ; D) 2 12 F3C H COOH OMe How many stereoisomers of 2,3-dichlorobutane exist? D A) 1; B) 2 ; C) 4 ; D) 3 13 A How many stereoisomers of 3-bromo-2-fluorobutane exist? A A) 4; B) 3 ; C) 2 ; D) 1 CHEM341 Quiz #9, page 2 14 Which of the following R/S assignment is correct? 1 2 F3C 3 4 HO CH3 F H A) 1-S, 2-R, 3-S, 4-S; 15 F COOH B) 1-S, 2-R, 3-S, 4-R ; C) 1-S, 2-R, 3-R, 4-S ; CH3 A F D) 1-R, 2-R, 3-S, 4-S Which of the following have the R configuration? 1 2 F Cl 3 F Ph Ph H H 4 H F D D Cl H A) 1, 2 and 4; B) only 1 and 2; C) only 1; D) only 4; E) only 1 and 3 16 Which of the following is the definition of chirality? A) The superimposability of an object on its mirror image; B) A molecule that has a carbon atom with four different substituents ; C) The non-superimposability an object on its mirror image ; D) A molecule with a mirror image 17 Which of the following statements is the most accurate regarding the reactions of (R)-4-methyl-1-hexene? A) The reaction with HBr results in a racemic mixture. B) The reaction with HBr results in a mixture of diastereomers. C) The reaction with HBr results in a mixture of unequal amounts of two diastereomers. D) The reaction with HBr results in a mixture of unequal amounts of two enantiomers. 18 C Which of the following is the definition of a pair of diastereomers? A) Any pair of enantiomers with two chiral centers B) A pair of stereoisomers each of which has two chirality centers C) A pair of stereoisomers with two different chiral centers D) A pair of stereoisomers with two chiral centers that are not-enantiomers 19. C D Which of the following have the S configuration? C A) only 1; B) only 2; C) only 1 and 2; D) 1, 2 and 3 20. Which of the following statements is true? A) All molecules that have chirality centers are chiral B) Superimposable structures are enantiomers C) All compounds with mirror images are enantiomers D) Isomers that are not superimposable on their mirror images are enantiomers CHEM341 Quiz #9, page 3 D