Third Practice Exam CHEM 256 - Organic Chemistry II Prof ...

Third Practice ExamCHEM 256 - Organic Chemistry II

Prof. BastinSpring 2015

Name

Pnovide clear, congise-answers using unambiquous, carefully drawn sFuctures (whereappropriate) for all of the questions. Good luck and enjoy!-

l) 112 pts

. 2) ll2pts

3) , 18 pts

a) /6 pts

5) t10 pts

6) tl2 pts

7) t12 pts

8) /8 pts

9) /6 pts

l0) 114 pts

Bastin - Third Practice Exam

l) (12 pts) Provide structures for the following compounds.

a) sec-butyl alcoholot\I

,N

b) cis-2-ethylcyclobutanol

c) (D-hex-3-en-2-one

c\;c\ 3

Chem 256 - Spring 2015

q.''\Aw

Ct

f) 3 4-dichlorohexandial

c\or \u

uAo

d) m-chl oroacetophenone

c-\e) dichloroacetaldehyde

O c\

Bastin - Third Practice Exam Chem 256 - Spring 2015

2) (12 pts) hovide either common or IUPAC names for the following compounds.

a)

b)

, \,5 -\.s"d\,."f -3-\re-Yc{c\>c\e

o

A qqdT\\Xr5. .sc t\*oqo\

(Z)-q-\oy.^.^\oc

tl) -\eFr\-o\A

d' ) -.v \obrcxrnr c"-\.\\\ \e

H

(q)- t - t"+c"c\o\

OH

b- l*ocu -5; -s -\l - ) \,e\""n=\


3) (8 pts) Identify the symmetrical relationship (homotopic, enantiotopic, diastereotopic) of theunderlined atoms in the following molecules.

a)Hec

,, cHs

lzHH

\"o .i\t$ .-

\,"..s\c.(eo\$(-

b)

c)H

Hsc /t\cH3H3c$y'sH.

H

\o sns\r$ .

4

\oonr\u g.- L


4) (6 pts) Indicate the number of peaks that a 1a; r3C-NMR spectrum and (b) 'H-NMR spectrum

of each of the following molecules would contain?,\ Nl f\Ru) .'t

\

b)

ao

H.C\

I\S

'N3

qt.}

3

3Ll

Cto

t\

..St') -AI

\tt

c)

Bastin - Third Practice Exarn

A"'^-.


5) (l-0-qts) Following -are thrye compounds with the molecular formula CnHrO, and three tH-NMR spec!.m. Assign each compound its corect spectmm and assign all signals to theircorresponding hydrogens.

"\ro-"n-tlo

(2)

-")- o

(3)

"\5t

b

A a oo

6


a

I. . :

': -:

nt t

,:..

c\, *$

\) c\!

2

2H 3H

I

3H

D

bq

( L) q\\3 nevt rc tt

\q\ . r no*\ \ r

e>o + C\\ s

6) ( l2 pts) hovide the structure of a compound with the molecular formula C.HO using the IRand 'H-NMR provided below. Justify your structure by assigning ALL the appropriate peaksin the IR and NMR spectra and with a short narrative describing what structural informationeach piece of data provided.

Du= q *- \r1,

A\s r\:Cz(* o S

e.$6rs^-\it

l0

Integration

\o* rps{t r^) s\c- c\ Qc^Ot*) re \

c)

;,1i

V.>41

f.

ril \k/Ft : tripbl

qv|ltgl-

t . ,-

7) ( l2 pts) Provide the structure of a compound with the molecular formula C3H6O2 using theIR, [H-NMR, and ''C-NMR provided below. Justify your structure by assigning ALL theappropriate peaks in the IR and NMR spectra and with a short narrative describing whatstructural information each piece of data provided.


cu. o\\.^dJ1> r\:

bt'13'n

3 C.- lbD n5 - o: 'tY *o'^"\

. l

c.^l\o:r.-r\ r c^fo>n

= 3-9'1t \

S\nte_ c\

c.^-,\'y[ \ r

Qt'€>{ri\ / N

e=a or d str.

lr\:, , ft \

L2- ,st C^tr\r\.\i(

to

Integration rH\--c$le

' 'C-NMR spectrum shows peaks at 14,60, and\)

ano

b

A.'

2H

'r'tl-

H@

r6s rtoo 12@

l*'-*+Ft

YD*, | \ - - tu.j)-\k" v.\ t\.( c\ f\uf lc^\i-r t


8) (8 pts) Draw the product(s), if any, of the following reactions. Indicate stereochemistrywhere relevant.

a)

1) 2Li. ether -2) CH3CH2CHO

3) H2O

,^-/\8,

te) or \A

b)

c)

d)

9o,)-

oF

t\, 0. $arz

NaOH.

3) CH3CH2COCH2CH2CH3


9) (6 pts) hovide the reagents needed to bring about the following transformations.

a)

i l B.\\-

-\-.

)) Eo

"5 D N,util..b.ul

\ ) b. \ , :

)) pe

b)

"o,. '/\,/

-\

ff

3)

c)oil

I

l0

Bastin - Third Practice Exam

l0) (14 pts) Provide a mechanism for the following reaction.

l) Ph3P2)nBuli

-3)O

il,t\-/

rv,/\.>1( \

Jf u'e';f=q


@

rafretxa( \P \r*

\ )

\ n6*?/t9J,

2D

,J*r\^sZI.-...-'V-

A,-aQha| -re"\ \

1La

,'-4-:( -Lij'.'\ \

l t

Third Practice Exam CHEM 256 - Organic Chemistry II Prof ...

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