DO NOT WRITE YOUR NAME UNTIL TOLD TO START! CHEM 8B Organic Chemistry II EXAM 2, Summer 2018 (300 points)

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1 ' UCSC Binder KEY Exam SS 18 Full First and Last Name Underline the first initial of your last name 1 (50) non (50) single step 3 (50) Puzzle 4 (50) men 5 (50) mean D NT WRITE YUR NAME UNTIL TLD T START! & Charles Courtney Nikkita John Jerien Gaby CEM 8B rganic Chemistry II EXAM Summer 018 (300 points) In each of the following problems use your knowledge of organic chemistry conventions to answer the questions in the proper manner Be sure to read all questions & instructions carefully paying special attention to directions to skip parts of problems Choose which problems to skip rather than doing every problem otherwise you may run out of time Make sure it is crystal clear which problems should and should not be graded by circling and X ing out those problems respectively You will have the entire class period to complete this exam ( hours) but hopefully you won t need it! You are welcome to use prebuilt models (50) Keep your eyes on your own paper Electronic devices of any gun kind are not allowed including cell phones and calculators Any student found using any of said devices or found Total / 300 examining another student s exam or cheat sheet will be promptly removed from the exam room and will receive a zero John on this exam Such an incident will be reported to the UCSC % Judiciary Affairs Committee which determines the consequences (it s not worth it) 151 Nina ' 1:30 tkhyrsai li?0o Cameron pm Courtney Functional Group Acid chloride Acid Anhydride Carboxylic Acid Esters Amides Suffix oyl chloride oic anhyride oic acid oate amide 495 checking Nikhila t 4:30 10:45 Leo ( am 11:30 :l5ts Charles Ii pickup Make sure proctor Jeriu to send exams for scanning? Gaby to to exams knows DRC call me w/ student questions after 1:30

2 CEM 8B Exam SS18 Last Name First Initial 1 Nomenclature & AcidBase Chemistry suffixes for acyl derivatives on the cover page o 0 (a) (15 points) Draw structures corresponding to any three of the following names Skip one by drawing a large X over it otherwise (i) (iii) will be graded typts (i) 4Dimethylpentanenitrile (ii) Acetyl chloride (ethanoyl chloride) 1 each * CN a (iii) Propyl benzoate (iv) NethylNmethylcyclohexane carboxamide 't ester TTT meet 49 ~5 ~l0 nr n i L (b) (15 points) Draw the structure of 4cyano8hydroxy59dioxononanoic acid to#neeety (c) (10 points) Circle the more acidic compound in each pair and provide the approximate pka of each on the line provided: less than (<) greater than (>) or about equal to (~) one of the memorized pka standards) 3 3 F vs vs Approximate < 19 pka (d) (10 points) Draw the enol tautomer of acetophenone 1 o FIzpEtF acetophenone (keto form) Ph* enol form oo pht 5pts 1

3 CEM 8B Exam SS18 Last Name First Initial pts each (50 points) Single Step Reactions Fill in the box with the reactant reagent(s) or product Choose any five (skip one by drawing an X over the box) otherwise (a) (e) are graded (a) 1 Br PBr 3 DTK Br 0 0 DTKBR 17 qtbsr * 3pts Br (b) (c) o ntnit Zpts ( hpµ8pts rt 0 Na excess Br! 0 Phthspt Et Na Ph #oµ ( mol) (1 mol) Mph } oo + (1 mol) Ph*a3r 5pts 'T (d) Br Ac PM^ 0 o Bruhn ^ I Brinn Br 5ptS Br (e) 0 pts [74 Atf o 't major (more stable) product antaeaatat 3 + (f) + Ph Men As I TF # + too *m M Ph

4 CEM 8B Exam SS18 Last Name First Initial o 3 (50 points) Reaction Puzzles CSE NE Puzzle 1 Fill in the missing reagents for reactions (a) through (f) on the lines below a b Br c C 5pts/ line d N f C e also (c) 1 Mg ok 3 0 (a) 1 B3 0 (c) 1 3 E Mg CZ 30 LiAl4 (b) PBB Brpts NaB40 ZK (d) same (e) DMP (f) 380 NMEZ NKD ' KMNY bleach ( Naao ) WPCC 0k \ Yzfor other amine any Puzzle Fill in the missing reagents and products in the boxes provided NaBy0/ Br NPh phnt agtgtadt ' o + a butnotmenffe NZ IM phltphtt less pts Cr 3 NACN othafwr 1 NaB 4 S 4 boxesi 8 0 CN NPh PK Phra 1 LIAIU 1 LiAl 4 SCl Z 8 80 N NPh 0 0 Ph ^NPh ph nc PMCI 0 0 Ph*Nz Ph^ 5pts 0 N+Ph 3

5 CEM 8B Exam SS18 Last Name First Initial 4 Basic Mechanisms Draw the arrowpushing mechanism for both reactions below including all arrows for proton transfers Include all intermediates with proper charges circled for each step positive FILL IN TE BLANK: Basic mechanisms should never have charges (a) (0 points) Draw the mechanism for the basic hydrolysis of the following acid chloride Phtcl g 0 Cl Na f + Cl :B f leptsoo GQ ' M 04 phky # ome Ph Eipno EYE 00 5pts 5ptS pts intmd Ioo= yih0 oo=teaitaa@ o oon~0 (b) (30 points) Draw the mechanism for the reduction of the lactone (cyclic ester) with lithium aluminum hydride followed by quenching with acid 1 LiAl possible 4 Q 3 + r opknymntatene 9h04 step q

6 > CEM 8B Exam SS18 Last Name First Initial 50 5 (0* points) Acidic Mechanisms CSE NE Draw the arrowpushing mechanism for either reaction below including all arrows for proton transfers Include all intermediates with proper charges circled for each step negative FILL IN TE BLANK: Acidic mechanisms should never have charges (a) The reaction of nitriles with Grignard reagents yields a ketone product This reaction goes through an imine ion intermediate which is then hydrolyzed under acidic conditions Draw the mechanism from the imine ion to the ketone product in the space below No mechanism necessary for the Grignard addition step N CN C 3 MgBr + + N + 4 Ketone Product Imine Ion (b) Draw the mechanism for the acidcatalyzed reaction of acetone with methanol to give the acetal product below excess C 3 3 C C 3 + 7E armdm 7C 3NA 't Z z NZ 8 in ab i # I #±n a Ifa Y?eEt * ZPCZ X ' tk#oisfaarr no Zptstrrnn \ + Acetal r per io at#tanateoaiiaieaiisateeoitatfok*b44tsopts/intnd Y z missing gintoaermoleaearfpfoko extraintmdiarmrs +0 B;a' CZC } intmd+0 intend 7 e t of no extra pts for though? µ0c3 X UT TE PART T SKIP WE WILL NT CSE TE BEST NE FR YU! 5

7 time # j # these a fights µp%js z 3450 ay y 0 's's in acidic Mech t charges = n ktoo 043 k 95 \ T f + totals 71 CZ %z 7 + fe ty c + saved! # its + C3 # µ oatsa@ C }

8 CEM 8B Exam SS18 Last Name First Initial (50 points) MultiStep Synthesis Carry out any two of the syntheses below using the starting material provided and any other reagents or carbon sources needed Draw the product after each synthetic step No mechanisms (a) 4 PIL Ph Ph (b) Ph Ph 1 V 0 8 oo 9 ran on pniektkpwno ' PKC 5 (g)10 LA or oktoo ttw#spnioakspn&ntsfiioheodspneepneeeeeptik 8fY 5µoF ~Br3* µ wµ ftpybassa %ooi3 'state ffnyii nx ootman into } 3 's feni i xafyiee reactdg 5 (c) N(C 3 ) (d) 3h08Phz # 3fPBr}3p# %CN ' 5h's 's'3if nhcn soclz 0 #ska LA *mnaya sot # well w/ bromide ( DMP Grignard 's better ) M rt A X UT TE TW PARTS T SKIP WE WILL NT CSE TE BEST NES FR YU!

9 maybe atoned into f DMP y sbr ; Ysouz f* ~ a it#eynkeito*atnlateiod~lyo 3 mlo + rhymer Mer } 5000 don't use this route! previous pgu Much shorter an * so ga b