Chem233_MT - © Prep101 Chemistry...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: © Prep101 Chemistry 233 Practice Midterm Total number of questions = 12 Total Marks = 92 Time = 2 hours Page 1 of 8 © Prep101 Q1 (3 marks) Arrange the following compounds in the order of decreasing acidity: OH CH3COOH CH3CH2OH A B H3C H CH3CH3 D E C Q2 (3 marks) Arrange the following compounds in the order of decreasing acidity: OH OH OH OH Cl Cl A CH3 Cl B C D Q3 (3 marks) Arrange the following compounds in the order of decreasing basicity: NH2 CH3NH2 A NH2 CH3NH B C Cl D Page 2 of 8 NH3 E © Prep101 Q4 (6 marks) Draw chemical structures, including stereochemistry where appropriate, of the followings: (a) The Newton projection of the most stable rotamer of: Cl Cl (b) The Fischer projection of: (Hint: more than one correct answer) HO H COOH H HO CF3 (c) The most stable conformer of cis-1-tert-butyl-4-methylcyclohexane. Page 3 of 8 © Prep101 Q5 (12 marks) Which term best describes the relationship between the following pairs of compounds? A. Geometric isomers B. Different conformers C. Enantiomers D. Diastereomers E. Identical F. Not isomers Et H (a) Cl Cl H Et Et HO Br HO Br Et CH3 CH3 MeOOC OH H (b) H HO COOMe F (c) F F I H H (d) H Cl HO F CH3 t Bu H Cl H3C I OH t Cl Bu (e) Cl Cl Cl Cl Me HO (f) Me Me Me Me OH Cl Me Page 4 of 8 © Prep101 Q6 (5 marks) Circle the correct E/Z and R/S designations for the following compounds: (E or Z?) H (R or S?) H Me H Me OH Br Br (R or S?) CHO H OH CH2CH2OH (R or S?) CH3 H H Ph (R or S?) Q7 (9 marks) For each pair of the following reactions, predict which reaction is faster, and indicate the type of the reaction (SN1, SN2, E1, E2): (a) NaOMe A Br DMSO OMe NaOMe B Br MeOH OMe (b) NaCN A I DMSO CN NaCN B I DMSO CN (c) A B Br MeOH OMe Br MeOH OMe Page 5 of 8 © Prep101 Q8 (12 marks) Give the structure of the major product in each of the following reactions. Write “No Reaction” if you think no product will be formed under the reaction condition. I NaOMe, MeOH ? o 60 C (a) NaCl, DMSO ? OH (b) Me Br Me (c) OTs Et (d) Me H t BuOK, tBuOH ? 60oC NaI, HMPA ? Page 6 of 8 © Prep101 Q9 (12 marks) The same starting material can be used to obtain a number of products by using different reagents. Provide the reagent(s) for each of the following reactions. Some reaction(s) may contain more than one step. A OH O OMe O O B OMe O O OMe OH C OH O D Q10 (10 marks) Provide a detailed mechanism for each of the following reactions: (a) NaH, Et2O HO O Br (b) OH conc. HCl Page 7 of 8 OH © Prep101 Q11 (9 marks) Consider compounds A-E below: Using the letter notation A-E, identify: (a) a compound that has the L absolute configuration (b) the compound(s) which will not exhibit mutarotation in water (c) the compound(s) which will give an achiral product upon treatment with NaBH4. Q12 (8 marks) Provide an efficient synthesis for the following multi-step transformation: H H Me Me O Page 8 of 8 ...
View Full Document

This note was uploaded on 10/24/2011 for the course CHEMISTRY chem taught by Professor David during the Spring '11 term at The University of British Columbia.

Ask a homework question - tutors are online