University of Rochester
Department of Chemistry
Chemistry 132 Lab Manual
CHEMISTRY 132 Laboratory
Table of Contents
Requesting a Temporary Lab Assignment (contact Dr. Hickey)
Lab Report Due Date
Electrochemistry Help Sheet for Tables 1 and 2.
The second column contains the observed cell potential. I used the Nernst equation to calculate the cell
potential we would have observed if we had used 1.0 M reagents the result, +0.458 V, is shown in the
Decide whether each of the nine compounds shown below 15 achiral or chiral For each
achiral compound, identify the symmetry element present that requires achirality.
For each of the followi
Jagger P Kn 6,45%; Hf
(0 59 El (Emmet: x)
Structure - Properties; Acids & Bases 1 1
ma! charge : Valem e tone 1w
~ # G" in 337 0"
Draw Kekule structures for each of the compounds below. Be sure to show all bonding (4* 4 5in
(b) Why does the rotation decrease to zero? Why doesn't it become negative?
meme. \m'-\>drur4 -. [mom-1 150 1a!) .3 same 5 m 1' it)
(c) If a large excess of radioactive iodide (131_I )_ is used and the rate constants for loss of
opt1 1ca ac t1vity and for
Alchohols Substitution & Elimination
1. The reaction of tetrahydrofuran with concentrated HBr gives a new compound, C4H90Br
This new compound shows a broad absorption 1n the IR at 3400 cm-1 that was not present in
the starting material When t
proceeds by a free radical chain mechanism. The initiation step is thought to involve the
generation [email protected]@ either by direct photolysis of $02C12 or by reaction of a
photochemically or thermally generated initiator radical (In-) with SOgClz to give InCI +
K 26 K 36 N?
P am W P a t was)
9 a3 e g 00% a >
CH3CI3 + ENHZ CH3CH2 + NH3 TXQJOGL
\h pKa 50 M pKa 36
$/ 0cm haw
mm: :- _ m i f1 :1 r
3. Draw complete Kekul structures of reactants and products using lines for bonds, 4,41: \
showing nonbonding electron
The free radical chlorination of ethylbenzene produces two monochlorination products
from reaction at the C-H bonds of the saturated carbons. Qinma www H ism-A.
5,0 31W 112 3 (1:1 as
CHZCH3 CHCH3 CHZCHZCI
T + H U-
AL\_33A12|0$ AL] :mmssx 1.03
H H a.
e v 5. RM:
As We will later learn, alkenes react with peroxycarboxylic acids (RC03H) to give three
membered ring cyclic ethers called epoxides. For example, 4~octene reacts with
peroxyacids to give 4,5epoxyoctane.
RCO3H / \
1. (a)._ Iodide ion is a good nucleophile and sodium iodide is quite soluble in acetone. On the
Other hand, sodium chloride and sodium bromide have low solubilities in acetone. As a
result, the reaction of alkyl bromi
Propose a reasonable reaction mechanism to explain the reaction. Assuming the alkyl group
rearrangements are concerted with loss of water from the protonated alcohol, use your
molecular models to show the orbital overlap that would occur in the rearrangem
'Podnehc Worm a.
REU. , Eweyeim. 3:de
" vWE MAW- mivgnmn A
@ 2% mm M L M
:0 H301 I mom
' I) l: LJHFM u
M 03 /K(0 0"! ] f->50LF k3)
J in 2mm mar
\ 3- Megflu
M WE? Mm W
at I with > 3
0 i am A/
0 )v HE: A
3. Three dicarboxylic acids, A, B, and C, all share the formula 2H3OQH) 2. They are all
catalyticailly hydrogenited (add H2 in the presence of a catalyst) to gluedicarboxylic
acids with the formula C2H4(C02H)2. Hydrogenation of both A and B gives the sa
2. Show how to carry out the synthetic conversions indicated in an efficient manner. Find as
many other interconversions as you can. If more than one step is required, show the
products for each step.
(a) , 9 e
K CH3C 5 CH OCH3 CH3CH2CH2NH2(CH3) Bl
- \ Br
Pfee m ' \ H I
Ohm 1M19gcnmhm cfw_C1\m:"5xr)
CL #6 ma,-
. mpmm +%m
RCIIJCH; > HM. H EON-1'13 Ha; R"
Q I ,1 , W
W m: \rIIQH
KW * CH a ECHLIOI I F
JQCHLEZCHS 'L CJQ, T "
3) 5; H. , In
-H-CJ I Hut
3 Tenmwm :1
COW [1' $01.;
IQHH oz: :~Icf
Additions to Alkenes III
Consider the following mechanistic proposal for the reaction of HBr with alkenes in the
presence of light and peroxides.
Initiation: ROOR l 2R0-
RO- + HBr > ROBr + H-
Propagation I: H0 + H2C=CH2 > H_CH2CH2'
a FMg Fgmijm! ., 13mm?)
Workshop #8 39%(1 -, uranium
" >1 1 1. g r-
Substitution / Elimination Reactions
1. For each of the potential Smreactions shown below explain whether the reaction is likely
or not (i.e. have K > 1 and/or proceed at a reasonabl
3. For each of the following reaction pairs, decide which would occur with a faster rate.
Clearly justify your answer (hint: Think about the reaction mechanism!).
1 in ether
(3E2 butyne + BIZ /-> trans 2 ,3 dibromo-2 butene
in ether .
trans-Z-butene + B12
Make a list of all of the addition reactions to alkenes that you know.
Organize the reactions according to:
(a) 7 mechanism: eIectrophilic, radical, stepwise via an intermediate vs. concerted, etc.
(b) regiochemistry for unsymmetrically substituted alkene
4-. For each of the following interconversions, circle the compounds that would predominate
at equilibrium. Clearly justify your choice.
(a) (3113(1H2CI12#l\/IgBl~ + CH3C E CH "_ /C;CH2CH3 + CH3C E C _MgB )
2 HC EC8 '1' H20
* CH3OH + CH3CH2NH3