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Final Exam for Organic I200pts (graded as 300pts)Name(This is an "open brain" exam, those who brought their brain, areencouraged to keep it open during the examination).1) Explain in a simple sentence what is meant in a chemical sense by thefollowing arrows. (7.5 pts)(a)(b)(c)(d)(e)Org 1 final Page 1
2) Name the classes of compound that the following molecules belong to(E.g. alkane, amide, etc). (13.5pts)ORO-HORO-RR-C C-RR O-HR O-RORRORHORClR NH2Org 1 final Page 2
3) Classify each of the following reactions as either an Elimination,Addition or Substitution. (7.5pts)(a)H3CH(b)(c)H3CHBrHIH BrH3CH3CCH3CH3Br H(d)H BrH3CH3CCH3HBr H(e) Ph C C:-HCH3Ph C C CH3 CH3-Br4) Draw Lewis structures (sticks for bonds, and dots for lone pairs) for thebelow two molecules. (6.5pts)CH3CH2OHCH3CO2H5) For the above two molecules, label the hybridization of all the carbonsand oxygens. (5pts)Org 1 final Page 3
6) Explain why ethanoic acid is a much stronger acid than ethanol. (10pts)7) On the below energy level diagram, label (a) the axes (b) the reactantsand products (c) any transitions states (d) ΔHo for the overall reaction (e)is this reaction exothermic or endothermic (f) is this reaction more likelyto proceed by an E1 or E2 mechanism? (10pts)Org 1 final Page 4
8) Explain why CH3 (methyl cation) has a different three dimensionalgeometry to CH3- (methyl anion). (12pts)9) Briefly explain which of the two above geometries best describes CH3 (methyl radical)? (3pts)Org 1 final Page 5
10)Name the following molecules in IUPAC form. (16pts)(a)(b)(c)(d)FOH(e)BrOrg 1 final Page 6
11) Asterix any chiral atoms in these molecules, and assign R or S to eachchiral center. CH2F12) Which of the above molecules are achiral, and in a sentence explainwhy they are achiral. (4pts)Org 1 final Page 7
13) Circle the more stable member of each pair, and in a sentence explainyour choice. (15pts) (a) (b)CH2(c)CH2(d) CH2(e)14) Name two of the geometrical conformations a cyclohexane moleculecan adopt. (2pts)15) Name the two different positions that the hydrogens of cyclohexanecan be located in the more stable geometrical conformation. (2pts)Org 1 final Page 8
16) Even in its most stable geometry, Bromo-cyclohexane can exist astwo conformers. Draw these two conformers, and label which is the morestable, and in a sentence explain why one is more stable. (10pts)17) Name the two allowed geometries for any elimination reaction toproceed. (3pts)Org 1 final Page 9
18) Which conformation of bromocyclohexane in (16) undergoes reactionwith potassium tbutoxide, and explain in a sentence your choice. (4pts)19) Provide a mechanistic explanation for the observed mixture ofproducts in the following SN1 reaction. 20) What would you expect the approximate ratio of these products to be?(2pts)Org 1 final Page 10
21)Give the products of 5 of the 6 following reactions. (15pts)1) NaNH2(a)H3CH1) Mg, Ether(b)(c)(d)IH3CH2) D2OHBr, PeroxidesHCH31) BH3.THFHCH32) H2O2, NaOHHCH31) Hg(OAc)2,H2OHCH32) NaBH4(e)(f)2) CH3CH2Br1) Na, NH3H3CH21b) Write the mechanism for one of the above anti-Markovnikov additions.(6pts)Org 1 final Page 11
22)Give reagents to perform 5 of the 6 following transformations. (15pts)(a)OHO(b)(c)OO C CH3OOH OOH3C(d)OOHNH2OHH OH(e)Cl HBr(f)H3CHHBr22b) Write the mechanism for either of the above alkyne reactions. (6pts)Org 1 final Page 12
Final Exam for Organic I 200pts (graded as 300pts) Name (This is an "open brain" exam, those who brought their brain, are encouraged to keep it open during the examination). 1) Explain in a simple sentence what is meant in a chemical sense by the following arrows. (7.5 pts) (c) (d) (b) (a) (e) Org 1 final Page 1
