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CO
2
Et
Pd(OAc)
2
(1 0 mol%)
O-menthyl- L-Leu
AgOA c, L i
2
CO
3
C
6
F
6,
80°C, 48 h
MeO
MeO
OH
O
MeO
MeO
98%
CO
2
Et
Scheme 9.124 Directed alkenylation in tandem with oxypalladation.
NH
NH
2
PdCl
2,
Cu (OAc )
2
AcOH, CF
3
CH
2
OH, 9 0°C
+
Ph
70%
Scheme 9.125 Directed alkenylation in tandem with aminopalladation.
H
N
O
MeO
+
O
O
MeO
N
MeO
[Pd(MeCN)
4
](BF
4
)
2
(10 mol% )
BQ , AgNO
3,
2% PTS
H
2
O, r.t., 48 h
O
MeO
O
89%
O
Scheme 9.126 N-Acylamine-directed alkenylation in aqueous micellar media.
The use of water and aqueous media is well known in regular Mizoroki-
Heck reactions. Nishikata and Lipshutz showed that water can serve as a
good solvent also for directed Fujiwara-Moritani reactions.
371
Moreover, in
the presence of the non-ionic surfactant PTS (polyoxyethylated tocopheryl
sebacinate), directed alkenylation of anilides with hydrophobic acrylates
bearing C
4
-C
12
alkyl tails takes place in the presence of a water-soluble silver
salt and benzoquinone as terminal oxidant. High yields of alkenylation
products are obtained either using Pd(OAc)
2
and strong acid HBF
4
or the
cationic palladium complex without acid (Scheme 9.126).
Under the conditions used, the substrates are partly solubilized in PTS
micelles and partly form a hydrophobic phase, hence vigorous stirring is
required to ensure effective mass transfer. High yields and monoalkenyl-
ation selectivity are obtained in this system, which demonstrates the good
prospects of aqueous systems for oxidative Heck reactions. A highly polar
aqueous system is likely to enhance the reactivity of cationic palladium
species.
A directed Fujiwara-Moritani reaction is more suitable for the develop-
ment of an enantioselective version, as the configuration of intermediate
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