Chemistry 232-002 (Prof. Grossman’s Section)Final ExaminationMay 2, 2002Name (please PRINT LEGIBLY) (last) (first)Student ID # Problem Score1(a–j). /502(a–c). /603(a–c). /454(a–d). /205(a–e). / 25 Total. /200Please observe the following.1) Write LARGE and LEGIBLY. This will help me assign partial credit.2) READ THE INSTRUCTIONS to each question CAREFULLY beforeanswering. Many, many points are not awarded on each exam becauseof the failure of students to read the instructions.TABLE OF ATOMIC WEIGHT MULTIPLES.C112 O116C224 O232C336 O348C448 O464C560 O580C672 O696C784C896 N114C9108 N228C10120 N342C11132 N456C12144 N57035Cl13579Br17935Cl27079Br2158TABLE OF IR STRETCHES IN INTERPRETABLE REGION. Functional Group Absorbance X–H region 2800–3500 cm–1O–H alcohol about 3500 cm–1, strong and broadN–H about 3300 cm–1, strongC–H 2850–3300 cm–1, strong to moderateC≡C–H 3300 cm–1C=C–H 3000–3100 cm–1C(sp3)–H 2850–3000 cm–1O=C–H 2750 cm–1O–H carboxylic acid 2800–3500 cm–1, strong and very broadC(sp) region 2200–2300 cm–1C≡N about 2250 cm–1, moderateC≡C about 2200 cm–1R–C≡C–H moderateR–C≡C–R no absorption seenC(sp2) region 1500–1800 cm–1C=O 1670–1780 cm–1, very strongacyclic and 6–membered cyclic ketones 1715 cm–13– to 5–membered cyclic ketones 1740–1780 cm–1aldehydes RCHO 1730 cm–1esters RCO2R´ 1740 cm–1amides RCO2NR´21670 cm–1any C=O adjacent to C=C or phenyl subtract 20–25 cm–1, sometimes moreC=C 1500–1650 cm–1(very sharp absorption; can vary from strong absorption to none.)TABLE OF TYPICAL 1H NMR RESONANCES.Type of C atom Chemical Shift (δ)saturated alkyl 0.5–1.5C=C–C–H, O=C–C–H, C≡C–H 1.5–2.5X–C–H (X= O, N, Hal) 2.5–4.5C=C–H 4.5–6.5aryl H 6.5–8.5O=C–H 7.8–10.5CO2H 11–14O–H, N–H variesTABLE OF TYPICAL 13C NMR RESONANCES.Type of C atom Chemical Shift (δ)alkyl C 0–50C(sp3)–N, O, Cl, Br 40–80C≡C 60–95C≡N 110–120C=C 100–160C=O 165–21011. (5 pts. each, 50 pts. total) Draw the major product of each of the followingreactions. Assume aqueous workup in all cases (that is, draw neutral products). Donot draw mechanisms!(a)CNLDA; PhCH2Br(b)EtOOOEtONaOEt(c)CO2HPhEtOHcat. H2SO4(d)CNCNexcess NaOH(e)OMeO22(f)NH2OSOCl2(g)OMeNH2H2, Pd/C(h)O2NBr2FeBr3(i)NOOCH3OLDA PhO(j)CO2EtLiAlH432. (20 pts. each, 60 pts. total) Design syntheses of the two compounds below fromthe indicated starting materials. Both syntheses will require two or more steps.Show each intermediate compound and all reagents you will need for each step.(Don’t panic if you can’t remember the reagents for a particular step; partial creditwill be given.) Do not show mechanisms.(a)OOOEtone or more alcohols4(b)OOH2Nbenzene5(c)OEtOOH63. (45 pts. total) Draw reasonable mechanisms for each of the following reactions.(a) (10 pts.)OOHcat. H+OO+7(b) (15 pts.)Br OEtOCH3MgBrOCH3CH38(c) (20 pts.)OHCH3CNH2SO4NHCH3O94. (5 pts. each, 20 pts. total) When the Friedel–Crafts reaction shown below is carriedout, four ketones are obtained. Two of the products contain the phenol (aromaticalcohol) functional group and the two others contain the ester functional group.HOAc2OAlCl3A + B + C + D(a) What spectroscopic technique would allow you to distinguish the two esterproducts from the two phenol products? Be specific about how the technique wouldallow you to distinguish them.(b) Draw the two products that contain the phenol functional group.(c) On the next page is a 1H NMR spectrum of one of the phenol products. Circle thecompound you drew in (a) which would give rise to this 1H NMR spectrum.(d) What 1H NMR feature would distinguish the other phenol product from theone you circled?105. (5 pts. each, 25 pts. total) Answer each of the following questions.(a) Why do Claisen condensations such as the one below require a full equivalent ofbase such as NaOEt to proceed to completion?EtO CH3ONaOEtEtOOCH3O(b) Why doesn’t the following reaction work as written?Ph OEtOOPh OHOLiAlH4(c) Why is F is an ortho–para director in Friedel–Crafts reactions, even though it isthe most electronegative element?11(d) Why doesn’t the following reaction work as written?MeNH2 + PhCH2Br MeNHCH2Ph(e) How many resonances will you see in the 1H NMR spectrum of the
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