Chemistry Reference
In-Depth Information
1-Chloroalkyl carbamates, prepared with phosgene (see Section 4.3.2 ''Carba-
mates''), react with hard nucleophiles such as methoxymethyl amine to afford
known ureas such as the herbicide Linuron [219].
OMe
H
N
H
N
H
N
O
Cl
N
OMe
93 %
Linuron
O
O
- CH
2
O
- HCl
Cl
Cl
Phosgenation of catechol affords o-phenylene carbonate, which is the key starting
material for the preparation of the insecticide Propoxur [220].
O
NHMe
OH
O
O
COCl
2
MeNH
2
O
Toluene/H
2
O
NaOH, 0-5°C
O
OH
OH
85 %
iPrBr
O
NHMe
O
O
Propoxur
An industrial process for the preparation of the systemic fungicide Oxadixyl has
been disclosed by Sandoz [221].
O
Cl
Cl
Cl
NHNH
2
O
O
HN
N
H
CO
N
N
H
CO
O
O
l
+
Cl
O
NaOH
O
O
O
O
N
N
Oxadixyl
