TWELVE EASY PROBLEMS

COMBINED PROBLEMS

FORMULA + INFRARED + NMR

SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/ (Mar 2002)

Spectra in these problems were obtained from:

Integrals (relative number of hydrogens)

are given as: 2

The integrals are the simplest ratio.

NOTE ON INTEGRALS:

Expansions are blue and printed above the baseline.

C4H10O

PROBLEM 1 INFRARED SPECTRUM

COMBINED PROBLEM #1

PROBLEM 1 NMR SPECTRUM

C4H10O

6

1

1

2

doublet multiplet doublet

COMBINED PROBLEM #2

C9H10O2

PROBLEM 2 INFRARED SPECTRUM

1719

PROBLEM 2 NMR SPECTRUM

C9H10O2

5

23

quartet triplettwo multiplets

COMBINED PROBLEM #3

C10H12O

PROBLEM 3 INFRARED SPECTRUM

1688

PROBLEM 3 NMR SPECTRUM

C10H12O

5 1

6

doubletseptet

COMBINED PROBLEM #4

C5H10O2

PROBLEM 4 INFRARED SPECTRUM

1712

C5H10O2

PROBLEM 4 NMR SPECTRUM

1

2

3

4

triplettriplet

two overlappingmultiplets (2 + 2)

COMBINED PROBLEM #5

C9H12

PROBLEM 5 INFRARED SPECTRUM

C9H12

PROBLEM 5 NMR SPECTRUM

5

1

6

septet doublet

COMBINED PROBLEM #6

C9H12

PROBLEM 6 INFRARED SPECTRUM

1610

C9H12

PROBLEM 6 NMR SPECTRUM

1

3

COMBINED PROBLEM #7

C6H10O3

PROBLEM 7 INFRARED SPECTRUM

1731 1719

C6H10O3

PROBLEM 7 NMR SPECTRUM

quartet triplet

2 2

3

3

COMBINED PROBLEM #8

C5H7NO2

PROBLEM 8 INFRARED SPECTRUM

1749

2266

C5H7NO2

PROBLEM 8 NMR SPECTRUM

2

2

3

quartet triplet

COMBINED PROBLEM #9

C9H12O

PROBLEM 9 INFRARED SPECTRUM

C9H12O

5

1 12

3

PROBLEM 9 NMR SPECTRUM

triplet quintet triplet

COMBINED PROBLEM #10

C8H12O4

PROBLEM 10 INFRARED SPECTRUM

1730

C8H12O4

quartet triplet

2

3

1

PROBLEM 10 NMR SPECTRUM

400 MHz

COMBINED PROBLEM #11

C7H12O4

PROBLEM 11 INFRARED SPECTRUM

1735

quartet triplet

C7H12O4

PROBLEM 11 NMR SPECTRUM

400 MHz

21

3

COMBINED PROBLEM #12

C8H7N

PROBLEM 12 INFRARED SPECTRUM

2229

PROBLEM 12 NMR SPECTRUM

400 MHz

C8H7N

4

3

CORRELATION CHARTS

acid

BASIC INFRARED KNOWLEDGE

OH 3600NH 3400

CH 3000

C N 2250C C 2150

C=O 1715

C=C 1650

C-O 1100

3300 3100 2900 2850 2750

3000

1800 1735 1725 1715 1710 1690

=C-H -C-H-CHO

C-H

ketoneesteracidchloride

aldehyde amide

anhydride : 1810 and 1760

CH2 and CH3 bend : 1465 and 1365

BASE VALUES

Also remember the effects of H-bonding, conjugation and ring size.

benzene C=C : between 1400 and 1600

EXPANDED CH

EXPANDED C=O

NMR Correlation Chart

12 11 10 9 8 7 6 5 4 3 2 1 0

-OH -NH

CH2FCH2ClCH2BrCH2ICH2OCH2NO2

CH2ArCH2NR2

CH2SC C-HC=C-CH2

CH2-C-O

C-CH-C

C

C-CH2-CC-CH3

RCOOH RCHO C=C

H

TMS

HCHCl3 ,

d (ppm)

DOWNFIELD UPFIELD

DESHIELDED SHIELDED

Ranges can be defined for different general types of protons.This chart is general, the next slide is more definite.

APPROXIMATE CHEMICAL SHIFT RANGES (ppm) FOR SELECTED TYPES OF PROTONS

R-CH3 0.7 - 1.3

R-C=C-C-H 1.6 - 2.6

R-C-C-H 2.1 - 2.4

O

O

RO-C-C-H 2.1 - 2.5O

HO-C-C-H 2.1 - 2.5

N C-C-H 2.1 - 3.0

R-C C-C-H 2.1 - 3.0

C-H 2.3 - 2.7

R-N-C-H 2.2 - 2.9

R-S-C-H 2.0 - 3.0

I-C-H 2.0 - 4.0

Br-C-H 2.7 - 4.1

Cl-C-H 3.1 - 4.1

RO-C-H 3.2 - 3.8

HO-C-H 3.2 - 3.8

R-C-O-C-H 3.5 - 4.8

O

R-C=C-H

H

6.5 - 8.0

R-C-H

O

9.0 - 10.0

R-C-O-H

O

11.0 - 12.0

O2N-C-H 4.1 - 4.3

F-C-H 4.2 - 4.8

R3CH 1.4 - 1.7R-CH2-R 1.2 - 1.4 4.5 - 6.5

R-N-H 0.5 - 4.0 Ar-N-H 3.0 - 5.0 R-S-HR-O-H 0.5 - 5.0 Ar-O-H 4.0 - 7.0

R-C-N-H

O

5.0 - 9.0

1.0 - 4.0R-C C-H 1.7 - 2.7

Monosubstituted

cis-1,2-

trans-1,2-

1,1-

Trisubstituted

Tetrasubstituted

C CH

R H

H

C CH

R R

H

C CR

H R

H

C CR

R R

R

C CR

R R

H

C CR

R H

H

Disubstituted

10 11 12 13 14 15

1000 900 800 700 cm-1

s s

m

s

s

s

m

=C-H OUT OF PLANE BENDING

ALKENES

10 11 12 13 14 15

1000 900 800 700 cm-1

Monosubstituted

Disubstituted

ortho

meta

para

Trisubstituted

1,2,4

1,2,3

1,3,5

BENZENES m

s s

s

s s

s

s

s

s

m

m

m

mOOPS

RING H’s

combination bands