文档介绍：HCJC BT1 2002
(i) Mr = 122 (NB: Mr = 123 is the M + 1 peak)
(ii)
δ/ ppm - - - -
Integral ratio 5 1 1 3
Multiplicity multiplet quartet singlet doublet
- CH next to
CH3
- aromatic - proton - H on OH - CH3 next to
protons deshielded group CH group
Deduction
- mono- because C - Because because
substituted bonded to broad singlet doublet
electronegative
atom O
Structure of A:
H OH
C H
C
H
H
C8H10O; Mr = 122
HCJC Prelim 2003
(a) See lecture notes pg 4 only.
(b) (i) The monomers of Terylene are:
O O
H2 H2
HO C C OH H O C C O H
Given that the molecular formula pound A has a 1:1 ratio of C :
H, A should contain an aromatic ring. Hence we decide that the
monomer of Terylene is 1,4-benzendioic acid.
The other part of the molecule must be an alcohol as B was hydrolysed
with sodium hydroxide.
-
C10H10O4 (B) – C8H5O3 = C2H5O Î CH3CH2O
1
Therefore B is:
O O
HO C C O CH2CH3
And A is:
O O
H C C O CH2CH3
(ii)
3
2
4 2
HCJC Prelim 2003
(a) Empirical formula of P: C3H6O
C H O
% : % : %
3 : 6 : 1
(b) Compound P:
δ/ ppm Integral Ratio Multiplicity Deduction
3 triplet CH3 next to CH2
3 triplet CH3 next to CH2
2 multiplet CH2
2 triplet CH2 next to CH2
2 quartet CH2 next to CH3
There is no OH functional group as there are no broad singlets.
O
H2 H2 H2
H3C C C C O C CH3
2
Compound Q:
δ/ ppm Integral Ratio Multiplicity Deduction
3 triplet CH3 next to CH2
3 triplet CH3 next to CH2
2 multiplet CH2
2 quartet CH2 next to CH3
2 triplet CH2 next to CH2
There is no OH functional group as there are no broad singlets.
O
H2 H2 H2
H3C C C O C C CH3
(c) Hydrolysis of the esters occurs on heating with sodium hydroxide.
O
H