Biomedical Engineering Reference
In-Depth Information
CO
2
Et
Bn
Bn
O
Bn
N
Cu(acac)
2
EtO
2
C
Ph
H
N
Ph
N
+
OEt
PhMe, reflux
49%
Ph
N
2
EtO
2
C
CO
2
Et
383
384
385
O
O
O
O
OEt
CO
2
Et
Cu(acac)
2
N
2
CO
2
Et
N
N
N
CH
3
CN, reflux
21%
Ph
Ph
Ph
Ph
Ph
Ph
386
387
388
O
O
O
O
OEt
OEt
N
2
N
2
N
N
Ph
Ph
Ph
Ph
386a
386b
O
O
N
2
N
2
EtO
EtO
Ph
EtO
Ph
Cu(acac)
2
N
2
+
H
N
O
O
HN
O
OH
N
CH
3
CN, reflux
64%
Ph
389
390
391
SCHEME 13.71
rearrangement. It was thought that the zinc present in solution may stabilize the anion
sufficiently to allow an ionic mechanism to dominate the rearrangement.
Saba and coworkers also demonstrated that the [2,3]-rearrangement strategy
could be used for the synthesis of azabicyclo[6.3.0]undecane systems containing
quaternary carbons adjacent
to the nitrogen atom [124]. Proline-derived
399
1. Zn(CH
2
I)
2
Et
2
O, 0°C
Ph
Ph
N
Me
N
Me
Ph
2.
n
-BuLi
THF, -30°C
Ph
393
392
76%
O
Ph
Ph
O
[2,3]
N
Me
Ph
Ph
Major
Me
N
1. Zn(CH
2
I)
2
Et
2
O, 0°C
2.
n
-BuLi
THF, -30°C
Me
72%
Ph
Me
O
395
396
N
Ph
Me
Me
Ph
Ph
O
Ph
O
[1,2]
394
N
Minor
Ph
Me
N
Me
Me
5%
Me
397
398
SCHEME 13.72
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