CHEMISTRY 213 XMAS 04 1 ANSWER ON THE GREEN COMPUTER ANSWER SHEET PROVIDED USING A PENCIL CHOICES MAY BE USED MORE THAN ONCE

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1 CHEMISTRY 213 XMAS 04 1 ANSWER ON THE GREEN COMPUTER ANSWER SHEET PROVIDED USING A PENCIL CHOICES MAY BE USED MORE THAN ONCE Using the molecules: A: CH 3 CH CHCO 2 CH 3 B: CH 3 CO 2 CH CHCH 3 C: CH 3 CH 2 NH CH 2 CH 3 D: N CH 2CH 3 CH 3 CH 2 E: CHO F: CHO CH 2 CH 3 OH H G: H H: HO H H and using the band frequencies (cm -1 ): a) 3400 b) c) 2750 d) 1760 e) 1735 f) 1725 g) 1705 h) 1695 i) 960 j) 700 Which infrared band frequency present in the first mentioned molecule, would most easily enable you to distinguish it from the second molecule 1 B from A 2 C from D 3 E from F 4 G from H 5 E from A 6 G from E Using the electronic transitions: a) F6F * b) c) F6B * d) n6b * e) n6f * f) B6F * g) L6M, charge transfer h) d6d and using the wavelengths (nm): a) 185 b) 210 c) 285 d) 320 e) 450 f) 650 g) 850 or molar absorptivities h) 10 i) 10 2 j) >10 3 Ferrocene (= di(cyclopentadienyl)iron) is a very bright orange 7 What type of transition causes this 8 Where would the absorption be (nm) 9 What would be its molar absorptivity 10 * Where (nm) is the B 2 6B 2 transition of CH 2 =CH-CO-CH 3 (MVK) 11 Then, what type of transition is the 320nm absorption of MVK 12 What would be its molar absorptivity

2 CHEMISTRY 213 XMAS After a drunk blew thru a breathalyser solution of bright orange potassium dichromate, the visible spectrum obtained at around 770nm showed an ε of about 0.5. Which type of transition from those on the previous page must the absorption centered at 770 nm arise from. Structures A-J: ICH 2 CH 2 CH 2 CH 2 Cl BrCH 2 CH 2 CH 2 CH 2 Br CH 3 SCH 2 CH 2 SCH 3 A B C C 4 H 9 -CO-O-CO-C 4 H 9 SH Br N OCH 3 D E F G P(OCH 3 ) 3 CH 3 (CH 2 ) 20 CHCl 2 CH 3 CHF 2 H I J In their mass spectra, which of structures A-J 14 would show an M-127 peak 15 would show an 11% M+1 peak 16 would show an M+2 peak, about 8% of the M+ peak 17 would show strong M and M+2 peaks, in a 3:1 ratio

3 CHEMISTRY 213 XMAS 04 3 GHB and Rohypnol are two of the date rape drugs and have the structure: 7 6 CH 3 OH N O O 2 N N COOH 13 F GHB Rohypnol using the proton chemical shift values: a) 1 b) 1.5 c) 2.3 d) 3 e) 4 f) 6.6 g) 7.2 h) 7.8 i) 10 j) What is the chemical shift of proton 1 19 What is the chemical shift of proton 3 20 What is the chemical shift of proton 4 (the COOH) 21 What is the chemical shift of proton 5 22 What is the chemical shift of proton 7 using the carbon chemical shift values: a) 15 b) 25 c) 40 d) 65 e) 105 f) 115 g) 130 h) 150 i) 170 j) What is the chemical shift of carbon 1 24 What is the chemical shift of carbon 2 25 What is the chemical shift of carbon 4 26 What is the chemical shift of carbon 6 27 What is the chemical shift of carbon 7 28 What is the chemical shift of carbon 8 29 What is the chemical shift of carbon 11 using the coupling constant (J) values (Hz): a) 0 b) 2 c) 4 d) 7 e) 12 f) 18 g) 36 h) 72 i) 136 j) What is the J value between protons 2 and 3 31 What is the J value between protons 12 and What is the J value between proton 10 and F

4 CHEMISTRY 213 XMAS OH 3 COOH 4 GHB 7 6 CH 3 N O 5 8 O 2 N N 13 F Rohypnol 9 Using the multiplicities: a) s b) d c) t d) q e) 5 lines f) 6 lines g) t of t h) d of d i) d of t j) d of d of d In the 500 MHz proton spectrum 33 What is the multiplicity of the protons 2 Assuming you can see $ 1 Hz couplings 34 What would be the multiplicity of proton 5 35 What would be the multiplicity of proton 10 In the proton coupled carbon spectrum (consider only 1 J couplings) 36 What is the multiplicity of carbon 9 37 What is the multiplicity of carbon 5 38 What is the multiplicity of carbon 7 39 What is the multiplicity of carbon 4 40 What is the likely spin system of the 3 protons of the benzene ring containing proton 5 at 500 MHz a) A 3 b) AA A c) ABC d) ABX e) A 2 X f) AA X g) AMX h) AA B i) A 2 B 41 How large is the M+1 peak in rohypnol relative to the Molecular ion a) 1% b) 2% c) 5% d) 8% e) 18% f) 26% g) 30% h) 35% i) 50% j) 100%

5 CHEMISTRY 213 XMAS 04 5 Using the following frequencies (Hz): a) 4.7 x 10 8 b) 5 x 10 8 c) 5.3 x 10 8 d) 5.3 x 10 9 e) 4.7 x f) 1 x g) 7.5 x h) 1 x i) 7 x j) 3 x At what frequency will the alcohol-oh of GHB absorb ir radiation 43 What resonance frequency would be used to detect the F of rohypnol, assuming the same instrument as Questions (γ F = 0.94γ H ) 44 Some airports are proposing to scan passengers using a frequency of Hz; what is the energy of a mole of airport photons (J mole -1 ) a) to b) to c) 10-9 to d) 10-3 to 10-4 e) 0 to 10 f) g) 10 4 to 10 5 h) 2 x 10 6 i) 3 x j) 2 x The molecule H 2 N-C/N is found in space Some of its relevant ir frequencies are at (cm -1 ) a) 3550 b) 3270 c) 2260 d) 1580 e) 1100 f) 700 g) Which corresponds to the C/N stretch 46 Which is the symmetrical N-H stretch 47 Which is the C-N stretch 48 Which is the N-H bend 49 How many fundamental frequencies are there: a) 7 b) 8 c) 9 d) 10 e) 13 f) 39 g) 44 h) 48 i) 49 j) 54

6 CHEMISTRY 213 XMAS 04 6 Some of the equations we have used this term are: E J = h 2 J(J+1)/8π 2 I ν = (1/2π)(k/μ) 1/2 ν = (γ/2π)b o N U /N L = e -ΔE/RT I = m 1 m 2 r 2 /(m 1 +m 2 ) Using the choices (cm -1 ) a) 20 b) 40 c) 60 d) 80 e) 120 f) 160 g) 200 h) 240 i) 320 j) If in the microwave spectra of H 2 O, the energy of the 1st line = 40 cm -1, what (in cm -1 ) will be the energy of the transition from E 1 to E 2 (E 0 = lowest energy level). 51 What (in cm -1 ) will be the energy of the 5th level, E The centre of the fundamental band for CO is at 2144 cm -1, and the spacing between the first two lines in the P branch of the rotational spectrum is 4 cm -1. What will be the frequency (cm -1 ) of the third line in the R branch a) 2128 b) 2132 c) 2136 d) 2140 e) 2144 f) 2148 g) 2152 h) 2156 i) 2160 j) In Question 52, what will be the frequency of the transition from v=0, J=2 to v=1, J=3 a) 2104 b) 2120 c) 2128 d) 2136 e) 2152 f) 2156 g) 2168 h) 2174 i) 2182 j) In Question 52, where would the first hotline of CO be a) 1068 b) 1072 c) 1076 d) 2140 e) 2150 f) 2190 g) 3216 h) 4260 i) 4288 j) In Question 52, what is the zero point energy for the C/O bond in J mol -1 a) 10-3 to 10-4 b) 10-2 to 10-3 c) 0.1 to 10-2 d) 0.1 to1 e) 1 to 100 f) 10 2 to 10 3 g) 10 3 to 10 4 h) 10 4 to 10 5 i) 10 5 to 10 6 j) 250

7 CHEMISTRY 213 XMAS If the H- 35 Cl stretching frequency occurs at 2990 cm -1, what would be the most reasonable value for the first overtone for the H-Cl stretch (cm -1 ) a) 8970 b) 6080 c) 5980 d) 5880 e) 3090 f) 2990 g) 2890 h) 1545 i) 1495 j) Where then would you expect the H- 37 Cl stretch to be observed (cm -1 ) a) 2143 b) 1500 c) 1495 d) 1490 e) 1447 f) 2990 g) 3016 h) 3350 i) 3677 j) If the spin quantum number for D is 1, how will the 1 H NMR spectrum of CHDCl 2 appear a) 1:2:1 triplet b) 1:1:1 triplet c) 1:3:3:1 quartet d) 1:1:1:1 quartet e) 1:4:1 triplet f) 1:1 doublet g) 1:3:1 triplet h) 3:1 doublet i) 1:3 doublet j) singlet Using a) singlet b) doublet c) triplet d) quartet e) d of quartets f) sextet g) septet h) nonet i) t of septets j) d of septets How will the CH signal of (CH 3 ) 2 CHNH 2 in its 1 H spectrum appear 59 at room temperature 60 at low temperature 61 How will the OH signal of (CH 3 ) 2 CHCOOH appear at room temperature

8 CHEMISTRY 213 XMAS 04 8 The following data may be useful in the next few questions NUCLEUS (all have I=1/2) 1 H 13 C 11 B 19 F 31 P 195 Pt 29 Si MAGNETOGYRIC RATIO (() % ABUNDANCE If 195 Pt nuclei resonate at 66.7 MHz on a 7 Tesla instrument, at what frequency (MHz) would 11 B nuclei resonate on this instrument a) 300 b) 278 c) 100 d) 98 e) 66.7 f) 55.6 g) 44.5 h) 22.2 i) 11 j) 9.9 If one had a sample of pure 195 PtF(CH 3 )Cl 2 63 What would be the width (Hz) of the signal in the platinum spectrum if the protons are NOT decoupled. [Assume 1 J PtF =500Hz, 2 J PtH =100Hz] a) 1800 b) 1500 c) 1200 d) 0 e) 150 f) 300 g) 450 h) 600 i) 800 j) If this sample was run on a 500MHz (proton) instrument, how many ppm would the most downfield line lie from the most upfield line [ 3 J FH =20Hz] a) 0.36 b) 0.34 c) 0.32 d) 0.30 e) 0.28 f) 0.26 g) 0.24 h) 0.22 i) 0.20 j) If one had a spectrometer which could measure all three nuclei on the same probe using the same magnetic field strength, in which order would the nuclei appear to resonate as the frequency of the probe was increased a) Pt<F<H b) Pt>F>H c) F<Pt<H d) F>Pt>H e) F<H<Pt f) F>H>Pt 66 If an proton appeared at 1050Hz downfield from TMS on a 300 MHz spectrometer Which of the following is this hydrogen most likely to be a) -COOH b) CH 3 -CH 3 c) -CHO d) Ar-H e) =CH 2 f) CH 2 I 2 g) (CH 3 ) 2 O h) (CH 3 ) 2 C=O i) CH 3 NH 2 j) H-OH 67 If two protons are coupled with J=7 Hz, what minimum difference in chemical shift must they have to appear first order at 360 MHz. Choices (ppm) a) 0.07 b) 0.11 c) 0.19 d) 0.28 e) 0.53 f) 0.83 g) 0.92 h) 1.06 i) 1.49 j) 1.88

9 CHEMISTRY 213 XMAS 04 9 Note the data at top of page 8 For the compound: A F 1 CH 3 3 Si H OCH 2 F 2 B making the normal assumptions about H-H coupling constants and low abundance nuclei, and using the choices (dqt means doublet of quartets of triplets) a) ddd b) tddd c) dddd d) qddtd e) ddqdt f) ddddt g) qddt h) tddq i) qttd j) dddtd 68 How would the 1 H spectrum of methyl protons 1 appear 69 How would the 29 Si spectrum appear 70 How would the 19 F spectrum of fluorines B 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(1)-H(2) coupling 72 What value do you expect for the H(1)-H(3) coupling 73 What value do you expect for the H(1)-F(A)coupling 74 What value do you expect for the F(A)-H(3) coupling 75 What value do you expect for the Si-H(3) coupling For F PPh 3 Pt Ph 3 P F 76 How would the Pt spectrum appear a) s b) d c) t d) dd e) ddd f) dddd g) ddt h) q i) tt j) 5 lines 77 What will be the intensity of the lines for one of the P in the 31 P NMR spectrum a) 1 b) 1:1 c) 1:1:1 d) 1:2:1 e) 1:4:1 f) 1:2:1:1:2:1 g) 3 1:2:1:4:8:4:1:2:1 h) 1:1:4:4:1:1 i) 1:2:1:2:4:2:1:2:1 j) H1:1:1:4:4:4:1:1: F Cl 2 5 FCH 2 CH 2 F H 3 P F Cl Pt Pt F Cl Cl F PH H 4

10 CHEMISTRY 213 XMAS J1 J2 J3 Answer using the following a = magnetically and chemically equivalent b = magnetically but NOT chemically equivalent c = chemically but NOT magnetically equivalent d = neither chemically nor magnetically equivalent 78 In molecule J1, H-3 and H-4 are 79 In molecule J2, F-1 and F-4 are 80 In molecule J2, H-2 and H-3 are 81 In molecule J3 {not 195 Pt}, F-3 and F-4 are 82 In molecule J3 {not 195 Pt}, P-1 and P-6 are 83 In molecule J3 {both 195 Pt}, Pt-2 and Pt-5 are The molecule M has 4 protons and 4 carbons. The 1 H- 1 H COSY and 13 C- 1 H HETCOR spectra are shown on the next page. 84 What is the connectivity in molecule M a) C 1 H A -C 2 H B -C 3 H C -C 4 H D b) C 4 H A -C 2 H B -C 1 H D -C 3 H C c) C 3 H D -C 1 H B -C 4 H C -C 2 H A d) C 2 H B -C 3 H D -C 1 H A -C 4 H C e) C 4 H C -C 1 H B -C 3 H A -C 2 H D f) C 1 H B -C 4 H C -C 3 H A -C 2 H D g) C 2 H D -C 4 H C -C 1 H A -C 3 H B h) C 1 H C -C 4 H B -C 2 H A -C 3 H D

11 CHEMISTRY 213 XMAS COSY A B C D A B C D HETCOR A B C D C-1 C-2 C-3 C-4

12 CHEMISTRY 213 XMAS THE OBJECTIVE IN THE FOLLOWING QUESTIONS IS TO SOLVE THE STRUCTURES. THERE ARE SOME QUESTIONS TO ANSWER ON THE GREEN COMPUTER SHEETS; YOU WILL DRAW YOUR SOLUTION TO EACH STRUCTURE ON THE YELLOW SHEETS. WORK SPACE IS PROVIDED AFTER EACH QUESTION, THIS WILL NOT BE MARKED; ONLY GIVE YOUR FINAL ANSWER ON THE YELLOW SHEETS, giving more than one answer leads to penalties. COMPOUND P (has only one type of functional group): C 8 H 12 O 2 85 How many DBE has compound P a) 0 b) 1 c) 2 d) 3 e) 4 f) 5 The 1 H NMR spectrum showed peaks at δ 3.3 (s), 2.3 (s) and 1.0 (s) in a 1:2:3 ratio. 13 C NMR * 200 (s) 42 (t) 38 (s) 30 (t) 15 (q) IR : two peaks close to 1715 cm -1 as only significant peaks 86 What functional group(s) must be present in P a) acid b) ester c) 2 aldehydes d) 2 ethers e) 2 ketones f) aldehyde/ketone g) ether/ketone h) ether/aldehyde i) alcohol/ketone DRAW YOUR STRUCTURE FOR COMPOUND P ON THE YELLOW SHEET IN THE PLACE PROVIDED.

13 CHEMISTRY 213 XMAS WORK SPACE - THIS WILL NOT BE MARKED

14 CHEMISTRY 213 XMAS Compound Q: C 8 H 14 O 2 87 How many DBE has compound Q a) 0 b) 1 c) 2 d) 3 e) 4 f) 5 13 C NMR * 168 (s) 137 (s) 125 (t) 65 (t) 30 (t) 27(q) 23(t) 14 (q) The IR and 300 MHz 1 H NMR spectra are given below: cm -1 only one band at ~900 is relevant multiplicities s s t s 5 6 t

15 CHEMISTRY 213 XMAS What functional group is present in Q a) alcohol b) ketone c) aldehyde d) ether e) alcohol-ketone f) alcohol-aldehyde g) ether-ketone h)ether-aldehyde i) acid j) ester DRAW YOUR STRUCTURE FOR COMPOUND Q ON THE YELLOW SHEET IN THE PLACE PROVIDED WORK SPACE - THIS WILL NOT BE MARKED

16 CHEMISTRY 213 XMAS Compound R: This gave in its high resolution mass spectrum its molecular ion at m/e (±0.013). The compound was known to contain chlorine. 35 Cl = Mass data for the CHNO containing fraction is given below: C H N O Mass C H N O Mass WRITE THE FORMULA FOR COMPOUND R ON THE YELLOW SHEET IN THE PLACE PROVIDED - you may need some of the data below! 89 How many DBE has compound R a) 0 b) 0.5 c) 1 d) 2 e) 3 f) 4 g) 5 h) 6 i) 7 13 C NMR spectrum : * 172 (s) 152 (d) 121 (d) 34 (t) 23 (t) 14 (q) The IR Spectrum and 1 H NMR spectrum are shown below cm -1

17 CHEMISTRY 213 XMAS multiplicities dt d q 6 t DRAW YOUR STRUCTURE FOR COMPOUND R ON THE YELLOW SHEET IN THE PLACE PROVIDED WORK SPACE - THIS WILL NOT BE MARKED

18 CHEMISTRY 213 XMAS Compound S: C 3 H 6 F 2 O 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: 3400 cm -1 Assume below that dt means J for d > J for t 13 C NMR * 83 (dt)(t when F decoupled), 70(dt)(d when F decoupled) The 1 H NMR spectrum is shown below. The peak at δ 3.2 exchanges with D 2 O Multiplicities: ddd* t5 s * the smaller couplings overlap DRAW YOUR STRUCTURE FOR COMPOUND S ON THE YELLOW SHEET IN THE PLACE PROVIDED

19 CHEMISTRY 213 XMAS WORK SPACE - THIS WILL NOT BE MARKED

20 CHEMISTRY 213 XMAS Compound T: C 10 H 14 ClN 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 (, > 10 3 ) 13 C NMR * 146(s) 132(s) 127(s) 126(s) 125(d) 119(d) 24(t) 22(t) 14(q) 13(q) IR spectrum: ~3400 cm -1 1 H NMR spectrum: Multiplicities: d d s q q t t The singlet at δ 3.8 exchanges with D 2 O From the information above, the general structure of T can be determined, but not necessarily which isomer!

21 CHEMISTRY 213 XMAS Use the following to determine which isomer is T. 13 C additivity constants for calculating 13 C chemical shifts in aromatics X C-X ortho-c meta-c para-c Cl alkyl ~ N< When a long range C-H HETCOR (3 bond) experiment was carried out, cross peaks were found for the protons at δ 2.4 with the C s at δ 146 and 125, while for the protons at δ 2.7, cross peaks were seen with the C s at δ 146 and 132. DRAW YOUR STRUCTURE FOR COMPOUND T ON THE YELLOW SHEET IN THE PLACE PROVIDED WORK SPACE - not marked

22 CHEMISTRY 213 XMAS WORK SPACE - not marked end

23 UNIVERSITY OF VICTORIA FINAL EXAMINATION, DECEMBER 2004 CHEMISTRY 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 (12), S (14), T (18), 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 10 8 m s -1 h = 6.6 x J s N = 6 x k = 1.38 x J K -1 R = 8.3 J K -1

24 FINAL EXAMINATION, DECEMBER 2004 YELLOW ANSWER SHEET CHEMISTRY 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]

25 STRUCTURE FOR COMPOUND Q [12 MARKS] FORMULA FOR COMPOUND R [1 MARK] = STRUCTURE FOR COMPOUND R [12 MARKS] STRUCTURE FOR COMPOUND S [14 MARKS] STRUCTURE FOR COMPOUND T [18 MARKS]