Nitrile Oxides, Nitrones, and Nitronates in Organic Synthesis : Novel ...

R
REACTIONS OF DIPOLAR 1,3-CYCLOADDITION ([3 + 2] CYCLOADDITION) 305
−
N
O +
N
R 2
( )n
R 1
( )n
H
N
R 1
H
+
R 2
Ph
O
H toluene
Δ
−
R
R
N
N
H
s s
N
O
H R 2
R 1
Ph
H
R
+
N
H
H
H
R
R
N
O
R1 R2 R 2
Ph
R N
O
s
R
R1 Ph
+
H
N
H
N Ph
+
O R R
s
2
R1 R = H or C 4H 9; R 1 = H or CH 3; R 2 = H, CH 3, C 3H 7 or Ph;
O
S
O2
S(O) xPh
Scheme 2.216
1. RNHOH HCl
MeONa, rt
2. toluene, 95°C
( )n
n = 1,2
x = 0,2 R = CH 3 or Bn
O
N
R 2
n = 1,2
R 1
Scheme 2.217
( ) n
Scheme 2.218
( ) n
O
N
R 2
R 1
+
N
R
H
H
( ) n
O
−
O
N
R
or
S(O)xPh
S(O)xPh
O
R 2
N
R 1
( )n