First ExamCHEM 256 - Organic Chemistry II

Prof. BastinSpring 2015

An quref )Name

1.

2.

3.

4.

5.

6.

7.

1) /15 pts

2) 115 pts

3) /20 pts

4) /15 nts

5) /10 pts

6) ll2ots

7) 113 pts

Total:

C ot (e \ . \ , n

(u\oeA\11

(crrr i \ \ .n

/100 pts

\ r +

f "> -u

)r, l +

5

t .s

Section ,/T

DO NOT ST til you are instructed to begin.

A-ntfo&th)tuo,qgln,, cover sheet - make sure they are all here!

Provide CLEAR, CONCISE answers using unambiquous, carefully drawn structures andmechanisms for the appropriate questions. Be sure to rea.d each question VERYCAREFULLY.

Db not provide mechanisms for synthesis and product prediction problems.

You may only use a pen or pencil and the materials provided in this packet on this exam.

If you have papers and/or books with you, they are to be left on the floor AT THEFRONT OF THE ROOM. If you need scrap paper please ask.

Cell phones must be OFF and placed on the table at the FRONT of the ROOM.

Bastin- Exam#I

1) (15 pts) Provide structures for the following compounds.

a) 3-chloro-l-hexyne

c\

b) (Z)- l-chl oropropene

,/>-\/\

. c\

c) 3-cyclopropyl- I -butene

d) (D-2,6-di methyl-2,6-octadiene

Chem 256 - Spring 2015

?

e) cis-2-pentene

a'f) 5-methyl-3-octyne

\

\-t?-x*+

Btnt i t t -E.rutr t# l Chetn 256 - Spring 2015

2l ( t -s Pts) Provide ei ther conrnlon of tLjPAC nar"ne s lbr thc fol lo lv ing colnpounds' l

a)

Q-i - ' '5, \ ; - \ ' \ - , l L\( \ i \ t

[ i l J - t) . , , ,_-, _ L\ *\ . . \ f . . , , \ . , ) l ,

\ .\ ( - , . : ] ,L\ c\ ' .cn\sr , . ) b- . \ o, . , ,

; l -

\ \= I '

w" \ - . : , {5. , \ ,1 . \ , " . - l . \ "1\ - \ - C'1 ; ' ro i , . . f l1,- , -

) -,t..r\'"1,...,n

r)

Br(t:

Ll - \ , )mo*J-!o, i \1nt

Bastin - Exam #I

,;\ chem 256 - spring 2015

/ t r ts. \= ,

3) (2o pts) praw kg@gct(c), if any, of the following reactions. Indicate stereochemistrywhere relevant.

a)

c)

HCI--->

t0.c"r..\

b)

1) H-BR". THFfrrofia6F-> t Ec\ctn\

#A

HCI(1 eq)

-

TEffifi

HCt >400c

d)

e)

0

s)

c\

+ a-^a.{t

+ tcrc^n-\

r#\^/\ \o

HBrlHzOz

-

4

-lF

{- €ecn \

Bast in-E.run#l

b)

C'H .( 'H = N,------r;

Chem 256 - Sprins 2015

--l-

t \c-. \

h)

4) ( l-5 pts) Provide the reagents needed to bring aboutthe tol lowing transtbrmations

a)

^

\ u "qi, ,.-\ \\F

3\$.ru-r, \r.o\\

\ \ .L\,\u c

/4'l l

c)

d)

e)

ABl l\,t-:,,

. ) -b' .)t \(\"i

Br

,,'A-^,/

-\

S'; . r tnpt . : . )t'\,/t'

ffis)

d- l l * r*

HaC

IJu.rtin - li.uurt lf I C'hem 256 - Spri t rg 2015

5) (10 pts) Predict the ] \4AJOR procluct and draw the curved-arrorv nrechanisrn fbr thefol lorvirrg rcact ion, Be sure to int l icate any stereochenristry. i f appropriate.

HO2C

H:C

)o2H 1,, \tsr z ()a f- r .Jr*' l

->cHr

. ) ' i , ( ) , ( r .\ : \ . ' - - \ : . \ ' . ' \ : \3

B{z I )1. ' t - r a.Jr ' l->

\_ra( o,tt

\. ',. .1 I ,,,,.,"'f-\, t ,'=-l" '""' : \ ' " / .

\ Lol l r $, ,

\uJ\ \

i{-,t 'III

\

. , ' r r +

I ' q ' , / , , ' , l -\ ( ' * r t r5r ( ( ' r . - \ r . . \ ' i r ' \

^/ ( < . \ ' ) ' , r

- t \ \ \ , : \1 ' r , ! . ,

kJ - { : - -* , . . . \ ' . . \ r ' ) v ' . ; , \ r1h q

\ ' \ L i* \ - ' ' ) \ '

" )

t "\5C Srr-r \-\

O\". . \ ( \ t - ' - r , L^1,. . 1." ,-c, \ \ - \ . \ - . 1.

cic.\.

Bastin - Exam #1 Chem256 - Spring20l5

6) (12 pts) The following reaction is quite similar to a reaction that we have previouslydiscussed, but it is not exactly the same. Since our aim in this class is to develop the abilityto understand new observations in the light of old knowledge, propose a curved-atrowmechanism for the reaction.

IR\,

(*\

Bastin - Exam #I Chem 256 - Spring 2015

7\ (13 pts) When cyclohexene is treated with a peroxyacid in water, trans-cylcohexane-I2-diolis produced. Provide a mechanism for this reaction, accounting for the observedstereochemistry.

-teg'--.-\.r.a.KK'vt

Q n.n-\

cfi\c.(f !t.*:\

loq an\', t\

eQ;r i &t