Introduction to

SPECTROSCOPY

4

2 :

13 (NMR) . proton NMR IR , . -NMR(FT-NMR) . , (methyl, methylene, aromatic, carbonyl ) . NMR . Proton NMR NMR . proton NMR 13 NMR . .

4.1 -13 -12, 0(zero) , NMR .(3.1 1 ) -13( 13C) I 2 . 13C proton(1H) . Proton 6000 . , -13 . 1.08% 13C . , 13C . 13C , 13C . 13C , 13C . . , 13C (magnetogyric ratio) ( 3.2), 13C proton . .( 3.3) NMR . Proton , Fourier (3.7 B) 13C-NMR . , proton scan .

188

, 13C proton 1/4( 3.2). , 7.05 Tesla , proton 300MHz 13C 75MHz . , proton 13C (transmitter) .

4.2 -13 A. -13 . 4.1 TMS methyl ppm . 13C proton (012 ppm) (0220 ppm) .

4.1

13

C ( TMS ppm ).

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189

4.1RCH3 R2CH2 R3CH CI CBr

13C 8-30 16-55 20-60 0-40 25-65 O O RCOR, RCOH O RCNH2 O O RCR, RCH C C C C C N 65-90 100-150 110-140 110-175

CN CCl CO

30-65 35-80 40-80

155-185 155-185 185-220

. proton NMR . . TMS (860 ppm) . (4070 ppm), alkene (100150 ppm). carbonyl (155220 ppm) . , , 1H 13C . 13C 20 .1 (3.11A) proton NMR NMR . (downfield shift) . 13C CX (one bond) , proton . Proton , . HCX (two bonds) . 1H-NMR . ( ). 13C-NMR - (downfield shift) - (upfield shift) . hexanol . 142.2 22.8 32.0 25.8 32.8 61.9 ppm CH3CH2CH2CH2CH2CH2OH C3(-) . 1 20 . . Macomber, R.,Proton-Carbon Chemical Shift Correlations Journal of Chemical , Education, 68(a), 284-5, 1991.

190

13C . 7 . 1H , (3.11B) C-13 . (one bond) , . 13C-NMR carbonyl sp2 . (anisotropy, 3.12) alkene . . , . (012 ppm) (0220 ppm). carbonyl . Carbonyl , carbonyl . 4.2 carbonyl 13C . ketone aldehyde . Carbonyl IR .

B.

13

C

13C . 13C . . . , (stereochemistry) .

4.2 Carbonyl nitrile 13C .

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191

m-Xylene . benzene 128.5 ppm. ( A8.7) benzene methyl . .

Ipso (- ) . m-Xylene . m-Xylene C1, C2, C4, C5 137.6, 130.0, 126.2, 182.2 ppm. . 8 13C . 13C . Levy, Macomber, Silverstein, Friebolin . 13C . . .

4.3 Proton 13C : -13 , 13C 2 . 13C . 2 13C (homonuclear) . 13C proton n 1 . (heteronuclear)() . 13C NMR . . Proton NMR () , . (three-bond coupling)(HCCH) . 4.3 13C proton . n 1 . 3 proton 13C (n 1 3 1 4) . proton 3.33 , . ( , one-bond coupling), J

192

100250Hz . NMR (HCCH, J 120 Hz) . 4.3 13C proton (proton 13C ); proton . 12C NMR . proton 13C ( ) proton- (proton-coupled spectra) (nondecoupled, ) . 4.4a ethyl phenylacetate proton 13C NMR . TMS (downfield) (14.2ppm) methyl . 3 (13CH, ) .(J 127 Hz) ( ) (J 1 Hz ) . (fine splitting) 2 proton(CH2) . 13C (HC13C). (J 02 Hz) , . Ethyl phenylacetate 2 CH2 . Ethyl CH2 (60.6ppm) . ( ). methyl 3 . Benzyl (41.4 ppm). carbonyl

4.3

13

C proton .

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193

(171.1 ppm) . ( ). benzyl CH2 . 127136 ppm . 4.12 13C . proton . 13CH . ethyl phenylacetate( 4.4a) . proton .

4.4 Proton- 13C (Proton

Decoupled

13

C Spectra)

13C NMR proton- (proton-decoupled spectra) . proton 13C . 13C NMR . , . Proton (decoupling), 13C NMR , proton . NMR

(20MHz) (b) Proton C (20MHz)(: Moore, J. A., and D. L. Dalrymple, Experimental Methods in Organic Chemistry, W. B. Saunders, Philadelphia, 1976.)13

4.4 Ethyl phenylacetate (a) Proton-

13C

194

decoupler( ) 2 . proton . proton 13C - . . 2 . 4.4b ethyl phenylacetate proton- . Proton- ( 4.4a) 4.3 . 2 proton . , . 2 ortho ( 2, 6) 2 meta ( 3, 5 ) . 4.5 proton- . 1-propanol 3 . , 13C . 4.5 ( 4.1) . , methyl . 77 ppm 3- CDCl3 . (2H) 13C (4.13). CDCl3 TMS .

4.5 1-Propanol proton- 13C-(22.5 MHz).

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195

4.5 Overhauser (Neuclear

Overhauser Enhancement, NOE)

proton- 13C , proton- . , . Overhauser (nuclear Overhauser effect) , Overhauser (nuclear Overhauser enhancement, NOE) . NOE (heteroneclear), . NMR . , NMR . ( ) , overhauser . (positive) (negative) . -1 -13 ; . . NOEmax 1 irr 2 obs

( )

( 4.1)

irr (magnetogyric ratio) obs . NOEmax . () 1 NOEmax Proton- 13C 3.2 NOE , NOEmax 1 267.5 1.988 2 67.28 ( 4.2)

(

)

( 4.3)

, 13C 200% . . NOE . -13 . 13C . NOE proton- 13C . -13 . NOE , 13C (/ ) . NOE (cross-polarization) . , . 4.6 . , (proton- 13C ) , (Boltzmann ) . (excited) .

196

, . NMR . Proton 13C NOE . 13C ( ) . CH3 CH2 CH C NOE , . - , r r3 . 1 r C sd H NOE f r 3

( )

, NOE . . , NOE . , . , dimethylformamide methyl 31.1 36.2 ppm . (lone pair) carbonyl CN .

Aldehyde syn methyl (36.2 ppm) anti methyl (31.1 ppm) NOE . . syn methyl aldehyde . proton- 13C NMR NOE . (decoupler) , (perturbation) . . . proton- 13C NMR NOE . NOE FID . NOE- proton- (NOE-enchanced proton-coupled spectrum) , NOE . 10.1 .

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197

4.6 : Overhauser (cross-polarization) Overhauser 4.6 . 1H 13C (two-spin system) . , - . , 13C NMR . 4.6 1H 13C 4 (N1, N2, N3 N4) . . (selection rules) ( (single-quantum transition) ). , proton (1H ) (13C ) . Proton (J ). (population) . N3 N2 . B . N1 , N4 . NMR .

4.6 AX .

198

(Level)N1 N2 N3 N4

(Equilibrium Population)B B B B

(X) . 13C :

13C N3 N4 B B N1 N2 B B (broad-band decoupling procedure) proton . Proton proton (saturated) . , 4.6 proton . N4 N2 , N3 N1 . .

(Level)N1 N2 N3 N4

(Population)B 1 2 B 1 2 B 1 2 B 1 2

:

13C N3 N4 B 2 B 2 1 1 1

N1 N2 B 2 B 2 1

. . Proton , (relaxation process) . . ( (double-quantum transition) .) . 4.6 W2

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199

N4 N1 . d .

(Level)N1 N2 N3 N4 :

(Population)B 1 d 2 B 1 2 B 1 2 B 1 d 2

13C N3 N4 B 2 - B 2 d d1 1

N1 N2 B 2 + d B 2 d1 1

d . d 2.988( 4.2 4.3 ). Overhauser . N3 N2 . ( (zero-quantum relaxation)). Overhauser . W2 ; .

4.7

13C

Proton- 13C . proton NMR . 13C . 2 . 4.5 NOE . NOE . ( ) CH3 CH2 CH 4 . 4 . 13C FT-NMR . 4.7 FT-NMR (pulse sequence). 13 . (FID) (aquisition time) . (delay) . FID . (1 ) Boltzmann .

200

13C , (relaxation) (4.8 ). 13C ( ), ( ) . , 13C FID . FID , . . ( ) . . 13C scan , / .

4.8 2 50/50. ( ) . - Boltzmann . 3.5 Boltzmann NMR ( 3.3). NMR . Boltzmann ( ). , , FID , . , , . , 1

4.7 FT-NMR .

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201

. . , , Boltzmann . Boltzmann (relaxation process) . NMR . (spin-lattice relaxation) (spin-spin relaxation). 1 (relaxation time) . (spin-lattice), (relaxation processes) . () . (spin-lattice relaxation time), T1 . , 1/T1 . (intramolecular) (intermolecular) - . - . . . Boltzmann . . CH, CH2, CH3 . - () . (spin-spin), (relaxation processes) . . . , . (phase coherence) . . ( ). NMR . - (spin-spin relaxation time), T2 . - . NMR . T1 (inversion-recovery method)2 . T2 . - ( ) - 1 Boltzmann (T2 T1). 2 (viscosity) T1 T2 . Proton T1 proton NMR - T1 . 13C NMR T1 . . 4 ( carbonyl ) . . Isooctane(2,2,4-trimethylpentane) toluene 13C T1 .2 .

202

Isooctane quaternary 2 (68). 4 23 3 2 13. Methyl ( 1, 5, 6, 7, 8) . Toluene NOE T1 . ipso 1 NOE . 13C NMR ipso . , T1 . Cyclopropane T1 37. Cyclohexane 20. Steroid cholesterol quaternary 12 T1 . Quaternary 46 T1 . Polystyrene T1 102 . 13 C NMR NOE - . . . 2,3-Dimethyl benzofuran . quaternary(ipso) 1 . 4.7 , T1 .

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203

4.9 Off-Resonance (decoupling) proton- . Overhauser / . . . , proton- . . Off-resonance (off-resonance decoupling) , . off-resonance 13C . n 1 3, 2, 1 . Off-resonance , . Off-resonance- ( , one-bond coupling) , . 2 ( , decoupler) proton scan ( off-resonance). decoupler proton . off-resonance decoupler . Off-resonance . proton . 4.8 1-propanol off-resonance . Methyl methylene . n 1 4.3 . TMS , methyl 0 ppm .

4.10

DEPT

Off-resonance . DEPT Distortionless Enhancement Polarization Transfer . DEPT FT- . DEPT off-resonance , . 10 DEPT . DEPT 13C 1H channel 3 . 3 4.7 (pulse sequence) .

204

13C (phase) . (duration) . , (plot) . DEPT 4 (subspectrum) . . Isopentyl acetate DEPT 4.9 .

13C . DEPT-45 , (protonated) . 172 ppm 6 carbonyl . CDCl3 (77 ppm) . (D 2H) 1H

4.8 1-Propanol off-resonance- 13C (22.5 MHz).

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205

. CDCl3 . (DEPT-90 ) . . 2 (25 ppm) . . DEPT-135 . , (phase) . CH CH3 CH2 ( ) . 4.9 isopentyl acetate . 21 ppm 22 ppm DEPT-90 CH3 . 13C 21 ppm 22 ppm . 21 ppm 5 CH3 , 22 ppm 1 CH3 . 25 ppm DEPT-135 DEPT-90 2 CH . 37 ppm CH2 , 3 . 53 ppm 4 CH2 .

4.9 Isopentyl acetate DEPT .

206

172 ppm 6 carbonyl . 13C . DEPT . CH , CH2 , CH3 . DEPT DEPT-135 . CH CH3 . DEPT . DEPT .

4.11

:

13C . 4.10 2,2-dimethylbutane proton- 13C . 3 methyl .

6 13C 4 . . methyl a (9 ppm) , 3 methyl b 29 ppm . 4 c 30 ppm

4.10 2,2-Dimethylbutane proton- 13C NMR .

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207

4.11 Cyclohexanol proton- 13C NMR .

methylene d 37 ppm . . 4.10 29 ppm (b) . 3 . 30 ppm 4 (c) . . NOE . . 4 , proton- 13C NMR (4.5, 4.7). 4.11 cyclohexanol proton- 13C . hydroxyl

4.12 Cyclohexene proton- 13C NMR .

208

4.13 Cyclohexanone proton- 13C .

4 . a c 2 b d . Hydroxyl d 70.0 ppm . . b d NOE . 2 hydroxyl . sp2 . cyclohexene 13C NMR ( 4.12). Cyclohexene . 3 . . , 2 . NOE . 4.13 cyclohexanone . Carbonyl . NOE ( ) carbonyl . 4 . carbonyl 4.1 .

4.12

100 175 ppm . , . (monosubstituted) benzene proton- 13C 4 . Ortho meta 2 . Proton

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209

(ipso ) NOE . Ortho meta 2 para . . Toluene ( 4.14) c d . (4.2B 8) .

Off-resonance proton- 13C benzene 3 . ispo . (ortho, meta, para) . 4.4b ethly phenylacetate proton- . (125135 ppm) 4 . Methyl 13 ppm methylene 2 . Methylene 61 ppm (41 ppm). Carbonyl (ester) 171 ppm . ( 4.1) . , (disubstituted) benzene 2, 3, 4 proton- 13C . dichlorobenzene .

4.14 Toluene proton- 13C NMR .

210

4.15 1,2-dichlorobenzene , . 13C NMR . benzene proton- 13C NMR 6 . .

4.15 Dichlorobenzene 3 proton- 13C NMR .

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211

4.13

13 NMR :

NMR (lock signal) (reference signal) , FT-NMR . 2H . proton , . . 13C NMR , . (heteronuclear coupling) . 4.16 chloroform-d dimethylsulfoxide-d6 13C NMR . Chloroform-d, CDCl3 13C NMR . deuterochloroform chloroform . 77 ppm . 4.16 . ( 2 ) proton- 13C ( 2 ) ; . (1:1:1) pascal 1:2:1 . 1 ( 2 ) , 1. 3 (2I 1 3) , 1, 0, 1. CDCl3 . , chloroform-d . 13C D (one-bond coupling) 45 Hz . 75MHZ 0.6 ppm (45HZ / 75MHZ 0.60 ppm). 1 2

, n 1

1 2 . multiplicity 2nI 1 ( 4.4)

n I . . 211 1 3 3 proton- .

23 1 1 4 2

13C

4.16 NMR . (a) Chloroform-d. (b) Dimethylsulfoxide-d6.

212

4.17 (n ).

Dimethylsulfoxide-d6, CD3SOCD3 carboxylic acid CDCl3 . 4.4 3 . 231 1 7 4.16 . 39.5 ppm 40 Hz . 1 1 2 Pascal (3.16 3.33) . . 4.17 . 4.18 . 4.18 1 1 . 0 . . Acetone-d6, CD3COCD3 dimethylsulfoxide-d6 13C . 29.8 ppm 206 ppm carbonyl . Carbonyl , (three-bond coupling) .

4.18 .

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213

Acetone-d5 acetone-d6 . -13 . -13 .

Proton(1H) NMR acetone-d6 acetone-d5 . 4.19 CD3COCHD2 CHD2 . 4.4 acetone-d5 proton . 221 1 5 .

CHD2 proton- 13C . ( 2 ) ( 1) . 4.4 . total multiplicity i (2niIi 1) Condition: I 1 2 i i 1 . I 2 . 0 . (CHD2) . total multiplicity (2113CH 13CD1

( 4.5)

1 1)(221 1) 10 2

, 10 . acetone carbonyl 2methyl . CD3(7 ) CHD2 10 . NMR 1H 13C 10 .

4.1413

Fluorine-19 C19F fluorine 4.19 Acetone-d5(CD3-COCHD2) 300MHz 1H .

214

. 4.20 4.21 . CFBr3 43.6 ppm 48.5 ppm (2 ) . 13C19F 368 Hz(4.9 ppm 75 MHz 368 Hz) . (one-bond two-bond coupling) . 124 ppm CF3 . CF 276 Hz( 2 122.49 ppm 126.17 ppm : 3.68 ppm 75 MHz 276 Hz). CH2 3 fluorine . 2 ( 2 61.01 ppm 61.47 ppm : 0.46 ppm 75 MHz 35 Hz).

4.15

Phosphorus-31

4.22 4.23 2 13C 31P . ( 1 4.22) methyl ( 2 ) J 56 Hz(12.1611.41 0.75 ppm; 0.75 ppm 75 MHz 56 Hz) . . . (phosphorus)

4.20 CFBr3 13C proton- (75 MHz).

4.21 CF3CH2OH 13C proton- (75 MHz).

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215

methyl (P-CH3) ; J 143 Hz(10.838.92 1.91 ppm; 1.91 ppm 75 MHz 143 Hz). (POCH3), 7 Hz(52.23 52.14 0.09 ppm; 0.09 ppm 75 M Hz 6.75 Hz).

4.22 Tetramethylphosphonium chloride 13C proton- (75 MHz).

4.23 CH3PO(OCH3)2 13C proton- (75 MHz).

216

*1. C3H6O2 proton- off-resonance- . .

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217

*2. proton- 13C . (a) (b) . .

218

*3. C4H10O 3 alcohol proton- 13C . DEPT off-resonance . s , d , t , q . alcohol .

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219

*4. C5H8O2 ester. . .

*5. C4H9Br 4 bromoalkane 1H 13C . .

220

4 2: 13 ,

221

222

*6. C7H14O 3 ketone 1H 13C . .

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223

7. C8H18 proton NMR 0.86 ppm . -13 NMR 26 ppm , 35 ppm . .

224

8. C5H12O2 proton NMR . -13 NMR . DEPT-135 DEPT-90 . .

Normal Carbon15 ppm 63 95

DEPT-135Positive Negative Negative

DEPT-90No peak No peak No peak

9. C5H10O proton NMR . -13 NMR . DEPT-135 DEPT-90 . .

Normal Carbon26 ppm 36 84

DEPT-135Positive No peak Negative

DEPT-90No peak No peak No peak

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225

10. C5H10O3 proton NMR . -13NMR . 1728 cm1 . DEPT-135 DEPT-90 . .

Normal Carbon25 ppm 55 104 204

DEPT-135Positive Positive Positive No peak

DEPT-90No peak No peak Positive No peak

11. C9H8O proton NMR . -13 NMR . 1746 cm1 . DEPT-135 DEPT-90 .

226

.

Normal Carbon44 ppm 125 127 138 215

DEPT-135Negative Positive Positive No peak No peak

DEPT-90No peak Positive Positive No peak No peak

12. C10H12O2 proton NMR . 1711 cm1 . -13 NMR DEPT135, DEPT-90 . .

Normal Carbon29 ppm 50 55 114 126 130 159 207

DEPT-135Positive Negative Positive Positive No peak Positive No peak No peak

DEPT-90No peak No peak No peak Positive No peak Positive No peak No peak

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227

13. C7H12O2 proton NMR . 1738 cm1 1689 cm1 . -13 NMR DEPT . .

Normal Carbon18 ppm 21 26 61 119 139 171

DEPT-135Positive Positive Positive Negative Positive No peak No peak

DEPT-90No peak No peak No peak No peak Positive No peak No peak

228

14. C7H12O3 proton NMR . 1.25 ppm 4.15 ppm . 2.56 2.75 ppm . 1720 1738 cm1 . -13 NMR DEPT . .

Normal Carbon14 ppm 28 30 38 61 173 207

DEPT-135Positive Positive Positive Negative Negative No peak No peak

DEPT-90No No No No No No No peak peak peak peak peak peak peak

15. C6H8Cl2O2 proton NMR . chlorine . 1739 cm1 . -13 NMR DEPT . .

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Normal Carbon18 ppm 31 35 53 63 170

DEPT-135Positive Negative No peak Positive No peak No peak

DEPT-90No No No No No No peak peak peak peak peak peak

16. C5H9NO4 proton NMR . 1750 1562 cm1 1320 cm1 . -13 NMR DEPT . .

Normal Carbon14 ppm 16 63 83 165

DEPT-135Positive Positivee Negative Positive No peak

DEPT-90No peak No peak No peak Positive No peak

230

*17. alcohol (elimination) . 6 alkene . 20.4 ppm , 123.4 ppm (proton- 13C NMR ). . .

*18. proton- 13C .

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231

*19. 4.14 toluene 13C NMR . 4.12 c d . 8 7 toluene . *20. 8 -13 .

232

Textbooks Friebolin, H., Basic One-and Two-dimensional NMR Spectroscopy, 2nd ed., VCH Publishers, New York, 1993 Gunther, H., NMR Spectroscopy, 2nd ed., John Wiley and Sons, New York, 1995. Levy, G. C., Topics in Carbon-13 Spectroscopy, John Wiley and Sons, New York, 1984. Levy, G. C., R. L. Lichter, and G. L. Nelson,Carbon-13 Nuclear Magnetic Resonance Spectroscopy, 2nd ed., John Wiley and Sons, New York, 1980. Levy, G. C., and G. L. Nelson, Carbon-13 Nuclear Magnetic Resonance for Organic Chemists, John Wiley and Sons, New York, 1979. Macomber, R. S., NMR Spectroscopy: Essential Theory and Practice, College Outline Series, Harcourt, Brace Jovanovich, New York, 1988. Macomber, R. S., A Complete Introduction to Modern NMR Spectroscopy, John Wiley and Sons, New York, 1997. Sanders, J. K. M., and B. K. Hunter, Modern NMR spectroscopy-A Guide for Chemists, 2nd ed., Oxford University Press, Oxford, 1993. Silverstein, R. M., and F. X. Webster,

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Spectrometric Identification of Organic Compounds, 6th ed., John Wiley and Sons, New York, 1998. Yoder, C. H., and C. D. Schaeffer, Introduction to Multinuclear NMR, Benjamin-Cummings, Menlo Park, CA, 1987. Compilations of Spectra Ault, A., and M. R. Ault, A Handy and Systematic Catalog of NMR Spectra, 60 MHz with Some 270 MHz, University Science Books, Mill Valley, CA, 1980. Fuchs, P. L., Carbon-13 NMR Based Organic Spectral Problems, 25 MHz, John Wiley and Sons, New York 1979. Johnson, L. F., and W. C. Jankowski, Carbon-13 NMR Spectra: A Collection of Assigned, Coded, and Indexed Spectra, 25 MHz, WileyInterscince, New York, 1972. Pouchert, C. J., and J. Behnke, The Aldrich Library of 13C and 1H FT-NMR Spectra, 75 and 300 MHZ, Aldrich Chemical Company, Milwaukee, WI, 1993. Pretsch, E., T. Clerc, J. Seibl, and W. Simon, Tables of Spectral Data for Structure Determination of Organic Compounds, 2nd ed., Springer-Verlag, Berlin and New York, 1989. Translated from the German by K. Biemann. Computer Programs that Teach Carbon-13 NMR Spectroscopy Clough, F. W., Introduction to Spectroscopy , Version 2.0 for MS-DOS and Macintosh, Trinity Software, 607 Tenney Mtn. Highway, Suite 215, Plymouth, NH, 03264; www.trinitysoftware.com Schatz, P. F., Spectrabook I and II MS-DOS

Version, and Spectradeck I and II, Macintosh Versions, Falcon Software, One Hollis Street, Wellesley, MA 02482; www.falconsoftware.com Computer Estimation of Carbon-13 Chemical Shifts C-13 NMR Estimate IBM PC/Windows , Software for Science, 2525 N. Elston Ave., Chicago, IL 60647. 13C NMR Estimation CS Chemdraw Ultra, , Cambridge SoftCorp., 100 Cambridge Park Drive, Cambridge, MA 02140. Carbon 13 NMR Shift Prediction Module requires ChemWindow (IBM PC) or ChemIntosh (Macintosh), SoftShell International, Ltd., 715 Horizon Drive, Grand Junction, CO 81506. HyperNMR IBM PC/Windows, Hypercube, , Inc., 419 Philip Street, Waterloo, Ontario, Canada N2L 3X2. TurboNMR Silicon Graphics Computers, , Boisym Technologies, Inc., 4 Century Drive, Parsippany, NJ 07054. Web sites http://www.aist.go.jp/RIODB/SDBS/menu-e.html Integrated Spectral Database System for Organic Compounds, National Institute of Materials and Chemical Research, Tsukuba, Ibaraki 3058565, Japan. This database includes infrared, mass spectra, and NMR data (proton and carbon-13) for number of compounds. http://www.chem.ucla.edu/webnmr/ UCLA Department of Chemistry and Biochemistry, in connection with Cambridge University Isotope Laboratories, maintains a website, WebSpecta, that provides NMR and IR spectroscopy problems for students to interpret.

234

They provide links to other sites with problems for students to solve. http://www.nd.edu/smithgrp/structure/workbook. html

Combined structure problems provided by the Smith group at Notre Dam University.