T. J. Senter et al. / Tetrahedron Letters 54 (2013) 1645–1648
1647
1. TFA (1.1 equiv.)
2. 10 mol %Grubbs II
0.05 M toluene
mw, 100 oC, 1 h
68%
and, for many systems, the only enantioselective preparation re-
ported to date.
Grubbs II
N
H
N
DCM, refux
N
H
or
Grubbs II
toluene, mw
Acknowledgments
-7
unsat
21c1
-7
unsat
The authors gratefully acknowledge funding from the Depart-
ment of Pharmacology, Vanderbilt University Medical Center and
the Warren Family & Foundation for funding the William K.
Warren, Jr. Chair in Medicine. Vanderbilt houses the Vanderbilt
Specialized Chemistry Center of the MLPCN and we acknowledge
MLPCN support (U54MH084659).
Scheme 5. RCM approaches to access the 1-azabicyclo[m.n.0]alkane cores.
1. TFA (1.1 equiv.)
N
m
N
H
n
= 1-3
m = 1-3
2. 10 mol %Grubbs II
0.05 M toluene
n
References and notes
n
m
mw, 100 oC, 1 h
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22
Scheme 6. Optimal RCM conditions for the enantioselective synthesis of the
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22a1
22a2
22a3
, 34%
, 29%
, 32%
N
H
N
H
N
H
22b1
, 59%
22b2
22b3
, 39%
, 30%
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22c2
22c3
, 34%
, 36%
, 33%
8067.
Figure 2. Mono-unsaturated 1-azabicyclo[m.n.0]alkane ring systems 22 synthe-
sized that encompass all of the key azabicyclic ring systems 1–9. Yields are overall
from commercial aldehydes 22, and ranged from 29–59%.
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