Chemistry Reference
In-Depth Information
H
N
ClCN
COCl
2
THF
NH
2
NH
2
Cl
N
H
N
N
CN
CN
O
Cl¯
Anh. NH
3
92 %
296
Key Intermediate
for
Isazofos
HCl/H
2
O
N
N
N
N
O¯ NH
4
+
OH
Cl
N
Cl
N
novel and safe synthesis of the herbicide Barban, used for the control of wild oats
[227].
H
N
Cl
O
Cl
NCO
+
O
OH
Bu
H
N
N
Bu
CH
2
O, Bu
2
NH
Mannich reaction
Cl
O
O
297
DCE,
e
-Cu
2
Cl
2
reflux, 2h
O
Cl
Cl
O
"ACE-Cl"
H
N
Cl
Cl
O
O
Barban
N-Dealkylation (N-debenzylation) of tertiary amines with phosgene or phosgene
equivalents has also been employed by a recently disclosed process for the prepa-
ration of o-(chloromethyl)phenylacetic acid derivatives, which are important in-
termediates for the preparation of microbicides. o-Chloromethylphenylacetic acid
derivatives 299 were prepared by reacting the benzylamine 298 with an alkyl
chloroformate or phosgene in the absence of water [228].
MeO
MeO
N
N
COOMe
Cl
ClOCOEt
Toluene
K
2
CO
3
COOMe
N
299
298
