Name: Date:
A-level Chemistry - Topic 18C: Organic Synthesis
met% Grignard Reagents
have
inside
them
of
Notes halogen ◦ alkane
(
usually
Br / I )
Grignard are
used to make
c- C bonds Mg
reagent
:
•
nucleophilic at
conditions :
dry ether ( solvent )
the carbon reflux
•
unstable
→ made
just before using it Hgv polar covalent bond
though ,
MgBr'e✓en
metal
H -
C
-
I -
☒
it ~
~
Grignard to =c=O
05
methanol reflux reagent
'
reflux
µ
+ At
+
µ
-
'
% '
R
*
8- C in grignard '
H
it ,H °
'
① R' R
'
+
1- 8
'
-
[ in methanol "
f g
OH H -
- -
c.
bond .
µ ,
-
É I -
-
H + Ht H H
'
OH
'
'
"
② add dilute H H R reflux
acid ( reduce
c=o )
.
_
.
-
-
"
if it if H
µ
OH
H -
c- Cdc -
H I c- I R
!
H
-
-
-
it it it Hit r
' '
ñe and
'
all
dry for
•
, Questions
1. Suggest a two-step synthesis of from using a
Grignard reagent in one of the steps.
Br
' I
→ M9B ' reflux
Mg
◦
+
◦
dry ether .
H
¥
fl
☒
◦ "
Mg Br reflex
c- d- c"
- •
2) ta -
→
•
Ht
if I
'
H
,
2. Suggest a two-step synthesis of from using a
Grignard reagent in one of the steps.
it Brt Mg → ' M9 " •
reflex
•
dry ether .
AMgBr+ ( 0, →
ÉOH
reflex
•
•
At
3. Show how pentan-3-ol can be synthesised from propanal and bromoethane using
ÉÉ
Grignard chemistry.
it it
It c- c- Br Mg
→←
Mg Br
-
+
-
ti't It if
" "
it it , it 9 ◦
the
•
H -
c- c- MgBr +
→ A- c- c- c- It
Hit
,
, •
µ
it f * ; µ
,
A-level Chemistry - Topic 18C: Organic Synthesis
met% Grignard Reagents
have
inside
them
of
Notes halogen ◦ alkane
(
usually
Br / I )
Grignard are
used to make
c- C bonds Mg
reagent
:
•
nucleophilic at
conditions :
dry ether ( solvent )
the carbon reflux
•
unstable
→ made
just before using it Hgv polar covalent bond
though ,
MgBr'e✓en
metal
H -
C
-
I -
☒
it ~
~
Grignard to =c=O
05
methanol reflux reagent
'
reflux
µ
+ At
+
µ
-
'
% '
R
*
8- C in grignard '
H
it ,H °
'
① R' R
'
+
1- 8
'
-
[ in methanol "
f g
OH H -
- -
c.
bond .
µ ,
-
É I -
-
H + Ht H H
'
OH
'
'
"
② add dilute H H R reflux
acid ( reduce
c=o )
.
_
.
-
-
"
if it if H
µ
OH
H -
c- Cdc -
H I c- I R
!
H
-
-
-
it it it Hit r
' '
ñe and
'
all
dry for
•
, Questions
1. Suggest a two-step synthesis of from using a
Grignard reagent in one of the steps.
Br
' I
→ M9B ' reflux
Mg
◦
+
◦
dry ether .
H
¥
fl
☒
◦ "
Mg Br reflex
c- d- c"
- •
2) ta -
→
•
Ht
if I
'
H
,
2. Suggest a two-step synthesis of from using a
Grignard reagent in one of the steps.
it Brt Mg → ' M9 " •
reflex
•
dry ether .
AMgBr+ ( 0, →
ÉOH
reflex
•
•
At
3. Show how pentan-3-ol can be synthesised from propanal and bromoethane using
ÉÉ
Grignard chemistry.
it it
It c- c- Br Mg
→←
Mg Br
-
+
-
ti't It if
" "
it it , it 9 ◦
the
•
H -
c- c- MgBr +
→ A- c- c- c- It
Hit
,
, •
µ
it f * ; µ
,
