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

340 NITRONES: NOVEL STRATEGIES IN SYNTHESIS
O
RO OR
550 a-d
( )n
N +
O −
551 n = 1
552 n = 2
a R = Me
b RR = CH 2CH 2
c RR = (RS, RS)- CHMeCHMe
d RR = (R,R)- CHPhCHPh
O
SPh
RO OR
559 a-c
H 3C
+
Fe(CO) Fe(CO)
3
3
564
O
S nPr
551 or 552
+
( )n
( )n
H H
O
553 a,b n = 1
556 a-c n = 2
O
560 a-c n = 2
562 b n = 1
OR +
N
O H
OR
H H
SPh
OR
+
N
O H
OR
R 1
Scheme 2.259
R 2
H N +
− O
R 1 = CH 3, i Pr, CO 2Et;
R 2 = CH 3, Ph, Bn, t Bu
CH 2CI 2
RT
Scheme 2.260
( ) n
R 2
R 1
N
O
( )n
N
( )n
H H
O
N O
OR
H
OR
554 a n = 1
557 a,c n = 2
O
RO OR
555 b n = 1
558 a-c n = 2
H H
O
N O
+
561 a-c n = 2
563 b n = 1
O
N
O
( )n
SPh
OR
H
OR
CH 3
O
Fe(CO)3
60%-85% yield
At least 25 : 1
endo : exo
R 2
R 1
N
[o]
O
nPr S
S nPr
Fe(CO) 3
CH3
O