HO \ /CH3. b. (2 pts) Which compound(s) (A-C) would be completely deprotonated by NaOH? (pka of water is 16

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1 All\ 1 rn 3l ~ ~')'\ CHEM 243 Exam #2A Spring (6 pts) Identify the compounds below as an: acetal, hemi-acetal, ketal, hemi-ketal, enol, imine, enamine or hydrate. HO o'c(ch 3 Q OCH 3 HO \ /CH3 c O'oH Q CH 3 ~OH Name tkjnl~ 14!~\ Name»~ dv--au. Name Eho/ 2a. (8 pts) For A-C below, circle the acidic protons and match the pka values listed below. Possible pka values: pka = 1 pka = 2, pka = 4 A HYO pka= 2D B pka= 1 C CH 3 oc6) ~ pka= 4o b. (2 pts) Which compound(s) (A-C) would be completely deprotonated by NaOH? (pka of water is 16 c. (4 pts) For the most acidic compound above, draw its deprotonated form (conjugate base). Be sure to show all pertinent resonance structures.

2 3. (8 pts) Circle what is true about oxidation/reduction a) An aldehyde is more reduced than an alcohol b) A ketone is a better fuel (has more potential energy) than an alcohol c) Sodium Borohydride (NaBH4) is considered a 'oxidizing is considered a reduced form of Carbon. 4. Orie of the 6 (A-F) molecules below represents NAD+ (nicotinamide adenine dinucleotide) and another represents NADH. (Assume the R group represents the rest of the molecule) a. (2 pts) Which structure represents NADH? _1=. b. (2 pts) Which structure represents a biological oxidizing agent? C (tji\f:l Q;)) R B R ONH, NH ~ 2 2 (fnh2 H(JNH NH2 ~.. l)[) ~ N N <f>n N H \ N D E I F R H...,R R c (2 pts) Which molecule could convert 2-propanol to acetone? (A-F) C- 5. a.(4 pts) Circle the compound(s) below that would be expected to decarboxylate (lose C2) when heated. II e ~

3 6. (1 pts) Draw the expected organic products of the reactions shown below. For the second reaction be sure to denote the location of 18 in the products. """r,tlf"" ~tj ~ OH OH H.. 7. a(7 pts) For the reaction below the ketone is reacted with LDA (lithium diisopropyl amide) to generate an enolate. Draw the structure of LDA and the enolate. Be sure to fully depict the enolate by showing all pertinent resonance structures. Lithuim diisopropyl amide 'enolate' b. (3 pts) Would lithium dimethyl amide be an effective base to replace LDA (why or why not?) NO_:.,,s... or s+.~-nraj ~m~ -w~\ol o..tt a.s &\ "~"Lt.or'h,iJ AS lvell c.~ C\ i?q s,.l ~

4 Choose to do either SA or SB. (you cannot do both). SA. (6 pts) Fill in the final product of the Malonic e~ter synthesis shown below. You do not have to draw the structures, after each step-just the final product. 3. HCl, H 2 -~r~v- ~ o.lj 4. heat - a.tcov!::.'i-'1\"'-b, SB (8 pts) Show how you would synthesize the compound below using the 4 steps of the Malonic ester synthesis (as in question 9A). You need to determine what your starting ester will be and compound added in step #2. Show the product of each of the 4 steps of the synthesis. OCH3 c?> 4. h.l.. t

5 9 (16 pts) Carefully draw the mechanism and product for one the reactions below(a-d). It is your choice on which you do. H+ HO~H +CH3H + ~CH, VlyoH c H+ H+

6 1. (14-2 pts each) Draw the mechanism and product for one of the reactions below (A, B or C). It is your choice on which you do. Note that they have slightly different point values depending on degree of hardness. t: which one :ur show). Ass~ume A. (14 pts) Aldol condensation-show mechanism for only one of the aldol condensation products (your choice h~~ is added at the end ;~:he reacti~:j ~j ~ + ~ ~ -.;_..- ~)~ M v I~ ~ 2 6ftttft: B (17 points) Intramolecular Aldol condensation. Determine what dicarbonyl compound would give the product below and then show the mechanism for this intermolecular Aldol reaction. HO" Dicarbonyl compound =7 + ketone CH3 Ho Michael Reaction Intermolecular Aldol condensation <>~~ =ctiz. o) ~ ~o 'o-\-\.,.-..

7 Extra credits 1. (2 pts) Attach your note sheet Do you feel having your notes created a positive effect on your studying for this exam as compared to not preparing the note. Rank on a scale from 1-1 (1 = very helpful in learning the material 1 = a detriment to learning the material) 2. (1 pt) If you were the Energy Commissioner for the World, what energy policy(s) would you promote? 3. (1 pt) Circle the organic molecule below that a Donkey could identify by name? H~ 6 4. ( 4 pts) The dinitro compound below has a pka of 3. Explain its high acidity (fully depict the conjugate base for full credit) ~ -t-)-::. ' &

8 CHEM 243 Exam #2B Spring 216 Name Sue, ~\f'~ -----=----~ la. (8 pts) For A-C below, circle the acidic protons and match the pka values listed below. Possible pka values: pka = 1 pka = 2, pka = 4 A ib pka= 'LD pka= C CH3 oce ~ pka= 4o b. (2 pts) Which compound(s) (A-C) would be completely deprotonated by NaOH? (pka of water is 16) A c. (4 pts) For the most acidic compound above, draw its deprotonated form (conjugate base). Be sure to show all pertinent resonance structures. 2. (8 pts) Circle what is true about oxidation/reduction a) An aldehyde is more reduced than an alcohol b) A ketone is a better fuel (has more potential energy) than an alcohol ~odium Borohydride (NaBH4) is considered a 'oxidizing agent' ~oal is considered a reduced form of Carbon.

9 3. (6 pts) Identify the compounds below as an: acetal, hemi-acetal, ketal, hemi-ketal, enol, imine, enamine or hydrate. HO ~'c( OH v H. cr HO\ c ""chch, Name fh~>\ 4. One of the 6 (A-F) molecules below represents NAD+ (nicotinamide adenine dinucleotide) and another represents NADH. (Assume the R group represents the rest of the molecule) a. (2 pts) Which structure represents NADH? V b. (2 pts) Which structure represents a biological oxidizing agent? _D R B R H(f ONH, NH NH 2 --=: ~NH 2 r(:; 2 NH 2 ~.. ~ ~ rf N N N e \ N E H c I D R H...,R F R (2 pts) Which molecule could convert 2-propanol to acetone? (A-F) D 5. a.(4 pts) Circle the compound(s) below that would be expected to decarboxylate (lose C2) when heated. HO~ b. (6 pts) Depict the decarboxylation mechanism and no product formed for one of the compound you circled above. H \ 1 11' b\o'li) I {, '' " l o\-\ c~'3-o-c~o ~ \ ~ t~d -c.~cl-l'l---,, c II

10 6. a(7 pts) For the reaction below the ketone is reacted with LDA (lithium diisopropyl amide) to generate an enolate. Draw the structure of LDA and the enolate. Be sure to fully depict the enolate by showing all pertinent resonance structures. Lithuim diisopropyl amide 'enolate' b. (3 pts) Would lithium dimethyl amide be an effective base to replace LDA (why orwhy not?) \. ~' e t\_/ ;~ -c~ 7. (1 pts) Draw the expected organic products of the reactions shown below. For the second reaction be sure to denote the location of 18 in the products. OH H 2 Cr 4 (excess)

11 Choose to do either SA or SB. (you cannot do both). SA. (6 pts) Fill in the final product of the Malonic ester synthesis shown below. You do not have to draw the structures, after each step-just the final product. 3. HCl, H 2 4. heat SB (8 pts) Show how you would synthesize the compound below using the 4 steps of the Malonic ester synthesis (as in question 9A). You need to determine what your starting ester will be and compound added in step #2. Show the product of each of the 4 steps of the synthesis.

12 9 (16 pts) Carefully draw the mechanism and product for one the reactions below(a-d). It is your choice on which you do. H+ - + ~CH, VlyoH c H+ H+

13 1. (14-2 pts each) Draw the mechanism and product for one of the reactions below (A, B or C). It is your choice on which you do. Note that they have slightly different point values depending on degree of hardness. A. (14 pts) Aldol condensation-show mechanism for only one of the aldol condensation products (your choice to which one your show). Assume heat is added at the end of the reaction. Ho- HYV + B (17 points) Intramolecular Aldol condensation. Determine what dicarbonyl compound would give the product below and then show the mechanism for this intermolecular Aldol reaction. Dicarbonyl compound C (2 pts) A Michael reaction followed by an intermolecular Aldol condensation. Note that you will need to determine what the structure of the starting Ketone must be. + ketone CH3 Michael Reaction Intermolecular Aldol condensation

14 Extra credits 1. (2 pts) Attach your note sheet Do you feel having your notes created a positive effect on your studying for this exam as compared to not preparing the note. Rank on a scale from 1-1 (1= very helpful in learning the material 1 = a detriment to learning the material) 2. (1 pt) If you were the Energy Commissioner for the World, what energy policy(s) would you promote? 3. (1 pt) Circle the organic molecule below that a Donkey could identify by name? H~ 4. (4 pts) The dinitro compound below has a pka of 3. Explain its high acidity (fully depict the conjugate base for full credit)