488
K. Tanaka
Table 23.8 Diels–Alder reaction of isoprene with N-substituted maleimides catalyzed by (R)MOF-9
OH
OH
(R)CO 2 H
CO 2 H
9
Me
+
N
O
O
R
N
O
O
R
Me
(R)-MOF-9
40 , AcOEt
Entry
R
Yield (%)
Ee (%)
1
M e
3 7
3 7
2
E t
8 1
7 5
3
n-Pr
11
5
4
P h
1 7
7
5
Cyclohexyl
18
0
with β-nitrostyrene, affording both 1:1 adduct and 1:2 adduct in excellent enantioselectivities and good diastereoselectivities; the results are summarized in Table 23.13.
We propose a stereochemical model for the transition state of the reaction, based on
the experimental results and the configurations of the products. The NO 2 group of
β-nitrostyrene coordinates with the Lewis acidic Cu site through an oxygen atom.
Preferential attack of the para-position of N,N-dimethylaniline on the Si-face of βnitrostyrene in the confined spaces in (R)-MOF-12 leads to the R-configured product
(Fig. 23.5).
K. Tanaka
Table 23.8 Diels–Alder reaction of isoprene with N-substituted maleimides catalyzed by (R)MOF-9
OH
OH
(R)CO 2 H
CO 2 H
9
Me
+
N
O
O
R
N
O
O
R
Me
(R)-MOF-9
40 , AcOEt
Entry
R
Yield (%)
Ee (%)
1
M e
3 7
3 7
2
E t
8 1
7 5
3
n-Pr
11
5
4
P h
1 7
7
5
Cyclohexyl
18
0
with β-nitrostyrene, affording both 1:1 adduct and 1:2 adduct in excellent enantioselectivities and good diastereoselectivities; the results are summarized in Table 23.13.
We propose a stereochemical model for the transition state of the reaction, based on
the experimental results and the configurations of the products. The NO 2 group of
β-nitrostyrene coordinates with the Lewis acidic Cu site through an oxygen atom.
Preferential attack of the para-position of N,N-dimethylaniline on the Si-face of βnitrostyrene in the confined spaces in (R)-MOF-12 leads to the R-configured product
(Fig. 23.5).