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CHEMISTRY 213 XMAS 03 1
ANSWER ON THE GREEN COMPUTER ANSWER SHEET PROVIDED USING A PENCILCHOICES MAY BE USED MORE THAN ONCE
Using the molecules:
O
Cl
COCl CONMe2 COOH O
NMe2
CHO
NMe2
OCOMeNH
O
A B C D E F G H
and using the band frequencies (cm-1):a) 3400 b) 3400-2400 c) 2750 d) 2150 e) 1800f) 1760 g) 1735 h) 1715 i) 1690 j) 960
Which infrared band frequency present in the first mentioned molecule, would most easily enableyou to distinguish it from the second molecule1 B from A2 C from G3 D from F4 H from E5 F from E6 G from C
Using the electronic transitions:a) σ�σ* b) π�π* c) σ�π* d) n�π* e) n�σ* f) π�σ*
g) L�M, charge transfer h) d�dand using the wavelengths (nm):a) 205 b) 255 c) 285 d) 400 e) 500 f) 650 g) 800or molar absorptivities h) 10 i) 102 j) >103
When thiocyanate (-SCN) is added to Fe3+, a very bright blood red color forms7 What type of transition causes this8 Where would the absorption be (nm)9 What would be its molar absorptivity
10 Where is the HOMO-LUMO transition of benzene (nm)11 Then, what type of transition is the 280nm absorption of benzoic acid12 What would be its molar absorptivity
CHEMISTRY 213 XMAS 03 2
13 After a drunk blew thru a ‘breathalyser’ solution of bright orange potassium dichromate(originally 0.1 molar), the spectrum obtained had an absorption centered around 770nm, but onlyshowed an absorption (A) of about 0.5. Assuming a 1 cm cell was used, which type of transitionfrom those on the previous page must the absorption centered at 770 nm arise from.
Structures A-J:
O
SCHBr3
F
CH3-S-CH3Cl
Cl
Cl
Cl
Br
Br
HS
SH
A B C D E
F G H I J
In their mass spectra, which of structures A-J
14 would show a 10% M+1 peak
15 would show strong M, M+2, M+4 and M+6 peaks, in a 1:3:3:1 ratio
16 would show an M+2 peak, about 8% of the M+ peak
17 would show an M-19 peak
CHEMISTRY 213 XMAS 03 3
The active ingredient in marijuana is known as �9-THC and has the structure:
O
OH
1
2
3
456
7
8
9 10
In �9-THC, using the proton chemical shift values:a) 1 b) 1.5 c) 2.3 d) 3 e) 4 f) 5.8 g) 6.6 h) 7.2 i) 7.8 j) 10
18 What is the chemical shift of proton 119 What is the chemical shift of proton 320 What is the chemical shift of proton 421 What is the chemical shift of proton 722 What is the chemical shift of proton 9
In �9-THC, using the carbon chemical shift values:a) 15 b) 25 c) 45 d) 70 e) 105 f) 115 g) 130 h) 150 i) 170 j) 200
23 What is the chemical shift of carbon 124 What is the chemical shift of carbon 225 What is the chemical shift of carbon 426 What is the chemical shift of carbon 527 What is the chemical shift of carbon 6 28 What is the chemical shift of carbon 729 What is the chemical shift of carbon 10
For �9-THC, using the proton coupling constant (J) values (Hz):a) 0 b) 2 c) 4 d) 7 e) 10 f) 12 g) 16 h) 24 i) 36 j) 48
30 What is the J value for protons 231 What is the expected J value for protons 4
CHEMISTRY 213 XMAS 03 4
Using the multiplicities:a) s b) d c) t d) q e) t of q f) 6 lines g) d of 6 linesh) d of d i) d of t j) d of q
In the 500 MHz proton spectrum of �9-THC32 What is the multiplicity of the protons 233 What is the multiplicity of proton 11 34 Assuming you can see � 1 Hz couplings, what would be the multiplicity of proton 7
In the proton coupled carbon spectrum of �9-THC35 What is the multiplicity of carbon 936 What is the multiplicity of carbon 1037 What is the multiplicity of carbon 738 What is the multiplicity of carbon 3
39 What is the likely spin system of the 5 protons of atoms 8-7-11 at 500 MHza) A5 b) AA’A”A’”A’”’ c) A3BC d) ABX3 e) A3X2
f) AA’A”MX g) ABCMX h) A3MX i) AA’A”XY j) ABCXY
40 How large is the M+1 peak in �9-THC relative to the Molecular ion
a) 1% b) 2% c) 5% d) 8% e) 13%f) 23% g) 30% h) 35% i) 50% j) 100%
41 When �9-THC is metabolized, one of the products produced is more urine soluble, andshowed a new s peak at about � 170 in the carbon spectrum, while losing a q peak at about � 30. Is this an:
a) acid b) aldehyde c) alcohol d) ketone e) ester f) ether
CHEMISTRY 213 XMAS 03 5
Using the following frequencies (Hz):a) 5 x 106 b) 1.25 x 108 c) 5 x 108 d) 1.25 x 109 e) 1.25 x 1011
f) 1 x 1014 g) 7.5 x 1014 h) 1 x 1015 i) 7 x 1015 j) 3 x 1018
42 At what frequency will the 5-OH of �9-THC absorb ir radiation43 What resonance frequency was used for Q35 assuming the same instrument as Q 32.
(�C = 0.25�H)
44 Some TV remote controls use a transmitting frequency of 5 x 1013 Hz; what is theenergy of a mole of “remote” photons (J mole-1)a) 0.2 x 10-28 b) 3 x 10-24 c) 3 x 10-10 d) 0.2 x 10-4 e) 0.03f) 0.2 g) 0.3 h) 2 x 104 i) 3 x 105 j) 2 x 1033
The compound (CH3)2S is very smellySome of its relevant ir frequencies are at (cm-1) a) 2950 b) 2850 c) 1420 d) 980 e) 690
Using what you know about related frequencies45 Which corresponds to the C-S stretch
46 What is the total number of fundamentalsa) 6 b) 9 c) 19 d) 21 e) 32 f) 39 g) 44 h) 48 i) 49 j) 54
47 Sulfur dioxide, SO2, causes most acid rain in the east. From what you know of otherfrequencies, where would you expect to find its highest ir frequency (cm-1).
a) 3500 b) 3000 c) 2750 d) 2250 e) 1700f) 1300 g) 1100 h) 900 i) 700 j) 300
A mixture of CO2 and NO2 shows infrared frequencies at (cm-1)a) 2348 b) 1618 c) 1318 d) 750 e) 667
48 Four of the above frequencies show P, Q and R branches, but one does NOT show a Qbranch - which is it
49 Which is the NO2 symmetric stretching frequency
CHEMISTRY 213 XMAS 03 6
Some of the equations we have used this term are:EJ = h2J(J+1)/8�2I� = (1/2�)(k/�)1/2
� = (�/2�)BoNU/NL = e-�E/RT
I = m1m2r2/(m1+m2)
Using the choices (cm-1)a) 20 b) 40 c) 60 d) 80 e) 120 f) 160 g) 200 h) 240 i) 476 j) 480
50 If in the microwave spectra of H2O, the energy of the transition from E1 to E2 is 80 cm-1,what (in cm-1) will be the energy of the 1st line (E0 = lowest energy level).
51 What (in cm-1) will be the energy of the 4th level, E3.
52 The centre of the fundamental band for CO is at 2144 cm-1, and the spacing between thefirst two lines in the R branch of the rotational spectrum is 4 cm-1. What will be thefrequency (cm-1) of the second line in the P branch
a) 2128 b) 2132 c) 2136 d) 2140 e) 2144f) 2148 g) 2152 h) 2156 i) 2160 j) 2164
53 In Question 52, what will be the frequency of the transition from v=0, J=4 to v=1, J=3
a) 2104 b) 2120 c) 2128 d) 2136 e) 2152f) 2160 g) 2168 h) 2174 i) 2182 j) 2190
54 In Question 52, where would the first overtone of CO be
a) 1068 b) 1072 c) 1076 d) 2140 e) 2150f) 2190 g) 3216 h) 4260 i) 4288 j) 4300
55 In Question 52, what is the zero point energy for the C-O bond in J mol-1
a) 1.3 x 104 b) 2.5 x 104 c) 1.3 x 103 d) 2.5 x 103 e) 1.3 x 105
f) 2.5 x 105 g) 1300 h) 2500 i) 130 j) 250
CHEMISTRY 213 XMAS 03 7
56 If the H-35Cl stretching frequency occurs at 2990 cm-1, what would be the most reasonablevalue for a hot line for the H-Cl stretch (cm-1)
a) 8970 b) 6080 c) 5980 d) 5880 e) 3090 f) 2990g) 2890 h) 1545 i) 1495 j) 1445
57 Where then would you expect the D-35Cl stretch to be observed (cm-1)
a) 2143 b) 1500 c) 1495 d) 1490 e) 1447f) 2894 g) 3016 h) 3350 i) 3677 j) 5200
58 If the spin quantum number for D is 1, how will the 13C NMR spectrum of CDCl3 appear
a) 1:2:1 triplet b) 1:1:1 triplet c) 1:3:3:1 quartet d) 1:1:1:1 quartete) 1:4:1 triplet f) 1:1 doublet g) 1:3:1 triplet h) 3:1 doubleti) 1:3 doublet j) singlet
Usinga) singlet b) doublet c) triplet d) quartet e) pentet (quintet)f) sextet g) septet h) octet i) d of pentets j) d of septets
How will the CH signal of (CH3)2CHOH in its 1H spectrum appear59 at low temperature60 at room temperature
61 How will the NH signal of (CH3)2NH appear at room temperature
CHEMISTRY 213 XMAS 03 8
The following data may be useful in the next few questions
NUCLEUS (all have I=1/2) 1H 13C 11B 19F 31P 195Pt 29SiMAGNETOGYRIC RATIO (γ) 27 7 9 25 11 6 5% ABUNDANCE 100 1 80 100 100 34 5
62 If 195Pt nuclei resonate at 66.7 MHz on a 7 Tesla instrument, at what frequency (MHz)would 29Si nuclei resonate on this instrument
a) 300 b) 278 c) 100 d) 98 e) 66.7f) 55.6 g) 27.3 h) 22.2 i) 11 j) 9.9
If one had a sample of pure 29Si(13CH3)4, and the 1JC-Si coupling is 150 Hz.
63 What would be the width (Hz) of the signal in the silicon spectra if the protons aredecoupled.
a) 1800 b) 1500 c) 1200 d) 0 e) 150 f) 300g) 450 h) 600 i) 750 j) 900
64 If this sample was run on a 500MHz (proton) instrument, at what ppm would the mostdownfield line lie [ assume 2JSi-H = 40Hz, 1JC-H=140Hz]
a) 0.36 b) 0.34 c) 0.32 d) 0.30 e) 0.28f) 0.26 g) 0.24 h) 0.22 i) 0.20 j) 0.18
65 If one had a spectrometer which could measure all three nuclei on the same probe usingthe same magnetic field strength, in which order would the nuclei appear to resonate asthe frequency of the probe was increased
a) Si<C<H b) Si>C>H c) C<Si<H d) C>Si>H e) C<H<Si f) C>H>Si
66 If an proton appeared at 1260Hz downfield from TMS on a 360 MHz spectrometerWhich of the following is this hydrogen most likely to be
a) -COOH b) CH3-CH3 c) -CHO d) Ar-H e) =CH2
f) CH2I2 g) (CH3)2O h) (CH3)2C=O i) CH3NH2 j) H-OH
67 If two protons are coupled with J=16 Hz, what difference in chemical shift must theyhave to appear “first order” at 300 MHz.
Choices (ppm)a) 0.07 b) 0.11 c) 0.23 d) 0.48 e) 0.53f) 0.83 g) 0.92 h) 1.06 i) 1.49 j) 1.88
CHEMISTRY 213 XMAS 03 9
For the compound:
PO CHF-CH3
F
F
1 2 3
using the choices (dqt means doublet of quartets of triplets)a) dddd b) tddq c) dtdt d) qttt e) dddtf) dddq g) qdtt h) tddt i) qttd j) ddtq
68 How would the 1H spectrum of methyl protons 3 appear69 How would the 31P spectrum appear70 How would the 19F spectrum of fluorines 1 appear
using the choices (Hz)
a) 2000 b) 200 c) 50 d) 10 e) 7 f) 2 g) 0
71 What value do you expect for the H(2)-H(3) coupling72 What value do you expect for the P-F(1) coupling73 What value do you expect for the P-F(2)coupling74 What value do you expect for the F(1)-F(2) coupling75 What value do you expect for the F(1)-H(3) coupling
PtPh3P
PPh3
Cl
Br
76 What will be the intensity of the lines for one of the P in the 31P NMR spectruma) 1 b) 1:1 c) 1:1:1 d) 1:2:1 e) 1:4:1f) 1:1:1:1 g) 1:2:1:1:2:1 h) 1:4:4:1 i) 1:4:1:1:4:1 j) 1:1:4:4:1:1
77 How would the Pt spectrum appear
a) s b) d c) t d) dd e) dddf) dddd g) ddt h) q i) tt j) 5 lines
CHEMISTRY 213 XMAS 03 10
PPPt
P P
F
FCF2F3C CF2 CF3
1
2
3
4
1
2
3
4
1 2 3 4
J1 J2 J3Answer using the followinga = magnetically and chemically equivalentb = magnetically but NOT chemically equivalent c = chemically but NOT magnetically equivalentd = neither chemically nor magnetically equivalent
78 In molecule J1, P-1 and P-2 are79 In molecule J1, P-1 and P-4 are80 In molecule J2, F-1 and F-2 are81 In molecule J2, H-3-up and H-4-up are82 In molecule J3, F3 are83 In molecule J3, F-2 and F-3 are
The NOESY and COSY spectra of a molecule M are shown on the next page.
84 What is the connectivity in molecule M (X = non spin active)
a) X-A-B-C-D-E b) A-X-B-C-D-E c) A-B-X-C-D-E d) A-C-D-X-B-Ee) A-X-B-E-D-C f) A-X-B-D-E-C g) A-B-C-X-E-D h) C-D-X-A-B-Ei) C-D-X-A-B-E j) A-X-D-B-C-E
CHEMISTRY 213 XMAS 03 11
A
A
A
A
B
B
B
B
C
C
C
C
D
D
D
D
E
E
E
E
NOESY
COSY
CHEMISTRY 213 XMAS 03 12
THE OBJECTIVE IN THE FOLLOWING QUESTIONS IS TO SOLVE THESTRUCTURES. THERE ARE SOME QUESTIONS TO ANSWER ON THE GREENCOMPUTER SHEETS; YOU WILL DRAW YOUR SOLUTION TO EACHSTRUCTURE ON THE YELLOW SHEETS. WORK SPACE IS PROVIDED AFTEREACH QUESTION, THIS WILL NOT BE MARKED; ONLY GIVE YOUR FINALANSWER ON THE YELLOW SHEETS, giving more than one answer leads to penalties.
COMPOUND P: C5H7OCl
85 How many DBE has compound P
a) 0 b) 1 c) 2 d) 3 e) 4 f) 5
13C NMR δ 195 (d) 65 (s) 40 (t) 33 (t)
IR : 2750, 1725 cm-1
The 1H NMR spectrum showed peaks at � 9.9 (s) 2.1 (t), 1.3 (approx 5 lines), in a 1:4:2 ratio.
86 What functional group must be present in P
a) alcohol b) ketone c) aldehyde d) ether e) acid chloride
DRAW YOUR STRUCTURE FOR COMPOUND P ON THE YELLOW SHEET IN THEPLACE PROVIDED.
CHEMISTRY 213 XMAS 03 13
------------------------------------------------------------------------------------------------------------------WORK SPACE - THIS WILL NOT BE MARKED
CHEMISTRY 213 XMAS 03 14
Compound Q: C5H8O2
87 How many DBE has compound Q
a) 0 b) 1 c) 2 d) 3 e) 4 f) 5
13C NMR δ 172 (s) 150 (d) 120 (d) 25 (t) 14 (q)
The IR and 300 MHz 1H NMR spectra are given below:
| | | 3400 2400 1695 cm-1 no clear bands
multiplicities d of t d 5 lines t
Note the expansion of the peak at � 7 of the 300 MHz spectrum ON THE NEXT PAGE!
CHEMISTRY 213 XMAS 03 15
Expansion, lines same as on previous page
88 What functional group is present in Q
a) alcohol b) ketone c) aldehyde d) ether e) alcohol-ketonef) alcohol-aldehyde g) ether-ketone h)ether-aldehydei) acid j) ester
DRAW YOUR STRUCTURE FOR COMPOUND Q ON THE YELLOW SHEET IN THEPLACE PROVIDED.
------------------------------------------------------------------------------------------------------------------WORK SPACE - THIS WILL NOT BE MARKED
CHEMISTRY 213 XMAS 03 16
Compound R: This gave in its high resolution mass spectrum its molecular ion at m/e 180.084 (±0.004). The compound was known to contain chlorine and one atom of P[=30.974] per molecule. The low resolution mass spectrum showed peaks at 180 and 182 ina 3:1 ratio. 35Cl = 34.969. Mass data for the CHNO containing fraction is given below:
C H N O Mass C H N O Mass1 - 5 2 114.005 5 6 - 3 114.0321 2 6 1 114.029 5 8 1 2 114.0552 - 3 3 113.994 5 10 2 1 114.0792 2 4 2 114.018 5 12 3 - 114.1032 4 5 1 114.042 6 - 3 - 114.0092 6 6 - 114.065 6 10 - 2 114.0683 - 1 4 113.983 6 12 1 1 114.0923 2 2 3 114.007 6 14 2 - 114.1163 4 3 2 114.030 7 - 1 1 113.9983 6 4 1 114.054 7 2 2 - 114.0223 8 5 - 114.078 7 14 - 1 114.1044 2 - 4 113.995 7 16 1 - 114.1284 4 1 3 114.019 8 2 - 1 114.0114 6 2 2 114.043 8 4 1 - 114.0344 8 3 1 114.067 8 18 - - 114.1414 10 4 - 114.091 9 6 - - 114.047
WRITE THE FORMULA FOR COMPOUND R ON THE YELLOW SHEET IN THEPLACE PROVIDED
89 How many DBE has compound R [note P is in the same group as N]
a) 0 b) 0.5 c) 1 d) 2 e) 3 f) 4 g) 5 h) 6 i) 7
13C NMR spectrum [P decoupled]: δ 36 (s) 20 (q)
When the P was not decoupled, each of these peaks appeared as a doublet
IR Spectrum: no functional groups present 1H NMR spectrum: only 1 doublet (all H’s) was present at � 1.3, J = 10 Hz
DRAW YOUR STRUCTURE FOR COMPOUND R ON THE YELLOW SHEET IN THEPLACE PROVIDED.
------------------------------------------------------------------------------------------------------------------
CHEMISTRY 213 XMAS 03 17
WORK SPACE - THIS WILL NOT BE MARKED
CHEMISTRY 213 XMAS 03 18
Compound S: C8H10O2
90 How many DBE has compound S
a) 0 b) 0.5 c) 1 d) 2 e) 3 f) 4 g) 5 h) 6 i) 7 j) 8
IR Spectrum:
| | 3300 1226 cm-1
13C NMR δ 156(s) 155(s) 129(d) 120(s) 110(d) 102(d) 22(t) 14(q)
The 1H NMR spectrum is shown below. The peaks at � 9 exchange with D2O
Integrations: 2 : 1 : 1: 1 : 2 : 3
Multiplicities: 2s d s d q t
CHEMISTRY 213 XMAS 03 19
DRAW YOUR STRUCTURE FOR COMPOUND S ON THE YELLOW SHEET IN THEPLACE PROVIDED.
------------------------------------------------------------------------------------------------------------------WORK SPACE - THIS WILL NOT BE MARKED
CHEMISTRY 213 XMAS 03 20
Compound T: C12H14O3
91 How many DBE has compound T
a) 0 b) 1 c) 2 d) 3 e) 4 f) 5 g) 6 h) 7 i) 8 j) 9
Compound T showed a uv band at ~265 nm (ε > 103)
13C NMR δ 206(s) 170(s) 155(s) 138(s) 129(d) 119(d) 40(t) 35(t) 29(q) 23(q)
IR spectrum:
| | | | 1770 1715 1200 840 cm-1
CHEMISTRY 213 XMAS 03 211H NMR spectrum:
Multiplicities: d d t t s s
DRAW YOUR STRUCTURE FOR COMPOUND T ON THE YELLOW SHEET IN THEPLACE PROVIDED.
------------------------------------------------------------------------------------------------------------------WORK SPACE - THIS WILL NOT BE MARKED
CHEMISTRY 213 XMAS 03 22
WORK SPACE - not marked
UNIVERSITY OF VICTORIA
FINAL EXAMINATION, DECEMBER 2003
CHEMISTRY 213 - F01
PRACTICAL SPECTROSCOPY
TIME: 3 HOURS
INSTRUCTOR: Dr Reg Mitchell
THERE ARE 22 PAGES + THIS COVER SHEET + YELLOW SHEET
[NOTE PAGES ARE PRINTED BOTH SIDES]
ANSWER QUESTIONS 1-91 [1 mark each] ON THE GREEN COMPUTER
SHEET WITH A PENCIL
DRAW YOUR STRUCTURES FOR COMPOUNDS P, Q, R, S AND T AND
GIVE THE FORMULA FOR R ON THE YELLOW SHEETS PROVIDED[P (12 marks), Q (12), R (14), S (14), T (16), formula of R = 1 mark][Total marks = 160]
MAKE SURE YOUR NAME AND REGISTRATION NUMBER ARE ON
BOTH THE GREEN COMPUTER SHEET AND THE YELLOW ANSWER
SHEET - DO THIS NOW
MAKE SURE THERE ARE 22 PAGES OF QUESTIONS - NOTE THEY
ARE PRINTED ON BOTH SIDES!
ELECTRONIC CALCULATORS ARE PERMITTED, BUT MUST NOT
CONTAIN STORED PROGRAMS OR FORMULAE
DATA YOU MAY NEED:
c = 3 x 108 m s-1 h = 6.6 x 10-34 J s
N = 6 x 1023 k = 1.38 x 10-23 J K-1 R = 8.3 J K -1
FINAL EXAMINATION, DECEMBER 2003 YELLOW ANSWER SHEET
CHEMISTRY 213 - F01 PRACTICAL SPECTROSCOPY
LAST NAME:
FIRST NAME AND INITIAL:
REGISTRATION NUMBER:
GIVE ONLY YOUR FINAL STRUCTURES ON THIS SHEET, SPACE FOR
ROUGH WORK IS PROVIDED ON THE QUESTION SHEET. Part marks
will be given for partial structures or partly correct structures; do NOT give
all the detail as to how you derived the structure.
MAKE SURE YOU SHOW ALL ATOMS INCLUDING HYDROGENS
IN YOUR FINAL STRUCTURE
MARKS FROM THIS SHEET [/69] =
STRUCTURE FOR COMPOUND P [12 MARKS]
STRUCTURE FOR COMPOUND Q [12 MARKS]
FORMULA FOR COMPOUND R [1 MARK] =
STRUCTURE FOR COMPOUND R [14 MARKS]
STRUCTURE FOR COMPOUND S [14 MARKS]
STRUCTURE FOR COMPOUND T [16 MARKS]