NMR Practice: C 4 H 10 O

NMR Practice: C4H10OGiven a molecular formula and an NMR spectrum, what is the structure of the compound?

2 H

3 H

NMR Practice – C6H12O2

integral

ratio 1 : 3.0

NMR : C4H8O2

8.00 7.00 6.00 5.00 4.00 3.00 2.00 1.00 0.00

q t

3 H2 H3 H

Common Patters for Proton NMR

1. triplet (3H) + quartet (2H)

2. large double (6H) + muliplet

3. large singlet (9H), ~1 ppm

4. multiplet ~7.2 ppm (4-5H)

5. singlet 3.5 ppm (3H)

6. singlet 2.1 ppm (3H)

ethyl group

isopropyl

t-butyl group

aromatic ring

-OCH3 group

H3C-C=O

(methyl ketone)

NMR Spectrometer - schematic

6

C4H7ClO2

NMR : C10H14

4 Hm

6 Hd

3 Hs

1 Hm

9

1H NMR : C6H12

10

1H NMR : C5H12O

(doublet)

br

11

1H NMR : C5H10O

1H NMR : C9H10

3 H doubletJ = 8 Hz

1H 1H

3H 2H

11 Hz