1 of 9 First Midterm Exam [Chapters 5-7 (Carey textbook)] CHE201A-C Professor Diver and Dr. Clizbe Oct. 24, 2014 Fall 2014 Version B (Exam duration: 1 h 30 min) NAME:______________________________________________ circle one: Dr. Clizbe or Dr. Diver and: Section ( A, B, C ) TA Name:____________________________ or CHE203 Page Total Possible Points (Possible Points per page) Points 2 30 3 14 4 22 5 22 6 30 7 20 8 15 9 Periodic Table TOTAL POSSIBLE: 150 YOUR TOTAL:_________ Molecular models are ALLOWED; calculators are NOT ALLOWED. No cell phones or extra paper will be provided. Fill out the exam in pen, use the back of the page if more room is needed.2 of 9 1. (30 pts) Circle the correct structure for each question. (a) Which of the following alkenes would have the highest heat of hydrogenation? (b) Which of the following molecules will not rotate polarized light? (c) Which of the following alkenes will have the highest molecular dipole? (d) Which of the following molecules will have a maximum of 8 stereoisomers? (e) Which of the following is the best leaving group? (f) Which of the following has no chiral carbons, but is a chiral molecule? H3CCH2CH3HOHCH3ClHHClCH3BrBrOHHBrHBrBr HHBrH HHHBrHH3CHH HHBrOHOHCH3BrCH3CH3ClOHF -Cl -Br -I-Cl ClFBrFBrHCH3HH3COOHOCH33 of 9 2. (14 points) (a) When performing the following elimination reaction, only ONE of the two expected products was formed. Circle the product that is formed during the reaction, and use a drawing (no words needed) to show why this is the product that forms. (7 points) (b) The kH/kD for the following reaction is 7.11. Briefly (in 2-3 sentences) explain what this value tells us about the mechanism of the reaction? (5 points) (c) Is the reaction in part b faster with hydrogen or deuterium? (2 points) +NaOCH3CH3OHC(CH3)3BrH3C(H3C)3CCH3HC(CH3)3CH3H3C(CH3)3CCH3C(CH3)3H3C(CH3)3CDDCH2BrbaseCH CH24 of 9 3. Stereochemistry (32 pts) (a) Indicate the correct configuration of the chiral centers and alkenes for the following molecules (R or S for chiral carbons, E or Z for alkenes). (2 pts each = 10 pts) (b) Indicate the relationship of each pair of molecules (constitutional isomers, enantiomers, identical, or diastereomers). (4 pts each = 12 pts) HCH3Br ClHOBrCH3HOHHCH2CH2BrHCH3ClHCHOHCH2ClHH3CBrH3CHHCH3BrCH3HClrelationship: ______________________________________CH3CH3Frelationship: ______________________________________CH3CH2HCH2CH2OHCH3H3CCH2CH2OHCH2CH3Hrelationship: ______________________________________F5 of 9 (c) Draw all four (4) diastereomers of CH3CH(OH)CH(OH)CH2CH3 as Fischer projections and label the enantiomeric pairs. (10 points) 4. Nomenclature of chiral molecules (12 pts) Draw the following organic molecules in the requested format. (6 points each) (a) (R)-2-bromopentan-1-ol as a Fischer projection (b) (2Z, 5S)-5-bromo-2-chloro-hept-2-ene as a line-angle drawing6 of 9 5. (30 points) Write the organic product(s) for each of the following reactions. Provide stereochemistry where applicable. All reactions will be assumed racemic; therefore, you only need to draw one enantiomer. Please indicate a major product, for reactions producing more than one product. (6 points each) (a) (b) (c) (d) (e) HBrperoxidesCH3BrKOHheatH3O+7 of 9 6. Reaction Mechanism Using the arrow formalism to show electron movement, provide a detailed mechanism showing each individual step of the reaction mechanism. Be sure each step is charge balanced and mass balanced. For full credit you must account for the use of all reagents and explain the formation of all products and by-products in the reaction. (20 pts) Br2H2OH BrHO CH3+ Br - + H3O+racemic mixture8 of 9 7. Synthetic Pathway Show how the following conversion can be accomplished in good yield. More than one step will be needed. Provide the reagent(s) needed for each step. Also, include the product of each step. (Mechanism, transition states, mechanistic intermediates are not needed) (15 points)9 of 9 ΔG = -RTlnKeq; R=1.987 cal • mol-1 • K-1 o.p. = !"#$%&%$!!"#$#%"&!!"!!"#$%&!"#$%&%$!!"#$#%"&!!"!!"#$!!"#"$%&'!( x 100 [α] = !!!"!! % e.e. = (% major enantiomer) – (% minor enantiomer) Fr87francium223.01973 45678 9 101112Cs55cesium132.9054Rb37rubidium85.4678K19potassium39.0983Na11sodium22.9897Li3lithium6.941H1hydrogen1.00794226.0254Ba56barium137.327Sr38strontium87.67Ca20calcium40.078Mg12magnesium24.3056Be4berylium9.01218Ac59227.0278La57138.9055Y3985.4678Sc2144.9559Raradium58104724022TiV Cr Mn Fe Co Ni Cu Zn23 24 25 26 27 28 29 30scandiumtitanium vanadium chromiummanganeseiron cobalt nickelcopperzinc47.88 50.9415 51.9961 54.9381 55.847 58.933254.6963.546 65.39ZrNb Mo Tc Ru Rh Pd Ag Cd41 42 43 44 45 46 47 48zirconiummolybdenumtechnetium ruthenium rhodiumpalladiumsilver cadmium91.244 92.9064 95.94 98.9063 101.07 102.9055 106.42 107.8682 112.411HfTa W ReOsIr Pt AuHg73 74 75 76 77 78 79 80hafnium tantalum tungstenrheniumosmium iridium platinumgoldmercury178.49 180.9479 183.85 186.207 190.2 192.22 195.08 196.96654 200.59niobiumyttriumlanthanumB C N O F Ne5 6 7 8910boron carbon nitrogenoxygen fluorineneon10.811 12.011 14.00674 15.9994 18.9984032 20.1797Al Si P S Cl Ar13 14 15 161718aluminumsiliconphosphorussulfur chlorineargon26.981539 28.0855 30.97376 32.066 35.4527 39.948Ga Ge As Se Br Kr31 32 33 343536galiumgermanium arsenicselenium brominekrypton69.723 72.61 74.92159 78.96 79.904 83.80InSn Sb Te I Xe49 50 51 525354indiumtinantimonytellurium iodinexenon114.82 118.71 121.75 127.6 126.904 131.29Tl Pb Bi Po At Rn81 82 83 848586thallium lead bismuthpolonium astatineradon204.3833 207.6 208.9804 208.98 209.987 222.0176He2helium4.002602actiniumTh90thorium232.0381Ce58cerium140.115Pa91231.0359Pr59140.907659260Nd PmSmEuGdTbDyHo Er61 62 63 64 65 66 67 68praseodymiumneodymiumpromethiumsamariumeuropiumgadoliniumterbiumdysprosiumerbium144.24 146.9151 150.36 151.965 157.25 158.925 162.50 164.930 167.26UNpPu AmCmBkCfEs Fm93 94 95 96 97 98 99 100uraniumplutoniumamericium curium berkelium californium einsteinium fermium238.0289 237.0482 244.0642 243.0614 247.0703 247.0743 251.0796 252.0829 257.0951neptuniumprotactiniumTm Yb69 70thuliumytterbium168.9342 173.04Md No101 102mendelevium nobelium258.0986