Biomedical Engineering Reference
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OH
Pd
2
(dba)
3
dppf
L3
Et
3
N
NMP, 60°C
then TFA
OMOM
CO
2
Et
SH
Me
CO
2
Et
Me
S
NHZ
CO
2
t-
Bu
I
40
41
42
NHZ
CO
2
H
Me
O
PPh
3
DIAD
CH
2
Cl
2
, reflux
O
H
58%
O
H
S
PPh
2
O
N
Fe
Me
O
PPh
2
O
NH
O
NHZ
L3
S
OH
OH
43
CO
2
Et
Griseoviridin
SCHEME 3.17
Synthesis of the lactone core of griseoviridin by Campagne and Moreau.
Me
Me
OMOM
Me
OMOM
Br
Br
Pd
2
(dba)
3
L1
,
t-
BuONa
PhMe, 130°C
sealed tube
59%
OTf
N
44
3 steps
N
OH
Me
Me
Me
O
Me
H
2
N
O
Me
O
47
46
Me
O
Me
Pd(OAc)
2
,
L4
Cs
2
CO
3
, PhMe
120°C
sealed tube
45
80%
P(
t-
Bu)
2
Me
N
O
L4
Me
Me
Me
Murrayazoline
SCHEME 3.18
Synthesis of (
)-murrayazoline by Chida and coworkers.
Recently, Beller and coworkers have devised a palladium-catalyzed synthesis
of alkyl aryl ethers via the exploitation of sterically hindered and air-stable bispyr-
azolylphosphine ligand
[43]. The regioselective arylation of primary alcohols in
the presence of secondary and tertiary alcohols has been reported for the first time.
This method allows a straightforward access to (hetero)aryl alkyl ethers in moderate
to good yields and was used in the synthesis of butoxycaine, an anesthetic drug
(Scheme 3.19).
L5
O
O
Ph
CO
2
Me
CO
2
Me
N
Me
Pd(OAc)
2
L5
,
n-
BuO
H
Cs
2
CO
3
PhMe
80°C, 3 h
N
N
2 steps
Me
Ph
Ph
N
PAd
2
N
O
Me
Br
O
Me
L5
Butoxycaine
SCHEME 3.19
Pd-catalyzed C-O coupling reaction of aryl halides with primary alcohols
Beller and coworkers.
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