Angewandte Chemie,
Год журнала:
2021,
Номер
133(41), С. 22340 - 22345
Опубликована: Июль 15, 2021
Abstract
The
Pd‐catalyzed
asymmetric
addition
reaction
of
β‐keto
acids
to
heteroatom‐substituted
allene
is
reported.
This
generates
β‐substituted
ketones
in
an
manner
through
a
branch‐selective
decarboxylative
allylation
pathway.
accommodates
various
alkoxyallenes
as
well
amidoallenes.
Angewandte Chemie,
Год журнала:
2022,
Номер
134(33)
Опубликована: Июнь 17, 2022
Abstract
As
a
fundamental
and
synthetically
useful
C−C
bond
formation
reaction,
the
aldol
reaction
is
one
of
most
versatile
transformations
in
organic
synthesis.
However,
despite
extensive
research
on
asymmetric
versions
unified
method
for
stereoselective
access
to
complementary
syn
anti
diastereomeric
products
remains
be
developed.
In
this
study,
we
developed
synergistic
palladium/chiral
Lewis
base
system
that
overcomes
inherent
diastereoselectivity
bias
reactions
and,
as
result,
allowed
us
achieve
first
diastereodivergent
coupling
alkoxyallenes
with
pentafluorophenol
esters.
Computational
studies
suggest
mechanism
involving
an
intermolecular
protonative
hydropalladation
pathway
rather
than
palladium‐hydride
migratory
insertion
pathway.
The
origin
stereochemistry
catalysis
rationalized
by
DFT
calculations.
Chemistry - A European Journal,
Год журнала:
2022,
Номер
28(24)
Опубликована: Март 9, 2022
Asymmetric
desymmetrization
has
been
demonstrated
to
be
a
powerful
strategy
for
building
stereocenters
in
asymmetric
synthesis.
Herein,
Pd/Cu
catalyzed
reaction
with
simple
geminal
dicarboxylate
is
reported.
A
wide
scope
of
imino
esters
bearing
an
aryl
or
heteroaromatic
group
were
compatible
this
bimetallic
catalytic
system.
The
reactions
proceeded
smoothly,
giving
the
desired
products
good
yields
high
excellent
regio-,
diastereo-,
and
enantioselectivity
(up
20
:
1
branched:linear,
>20
dr,
>99
%
ee).
Notably,
favored
branched
selectivity,
which
unusual
Pd-catalyzed
allylic
alkylation
reaction.
In
addition,
standard
product
could
easily
transformed
other
valuable
molecules
such
as
chiral
alcohols,
carbamates,
organic
boron
compounds.
Furthermore,
DFT
calculations
conducted
explain
origin
selectivity.
Angewandte Chemie,
Год журнала:
2022,
Номер
134(36)
Опубликована: Июнь 28, 2022
Abstract
An
unprecedented
hydroalkylation
of
racemic
allylic
alcohols
and
ketimine
esters
enabled
by
Cu/Ru
relay
catalysis
has
been
developed
via
merging
the
ruthenium‐catalyzed
asymmetric
borrowing‐hydrogen
reaction
with
a
copper‐catalyzed
Michael
addition
in
one‐pot
procedure.
The
current
method
enables
efficient
preparation
highly
functionalized
δ‐hydroxyesters
bearing
1,4‐nonadjacent
stereocenters
good
yields
high
levels
diastereoselectivity
excellent
enantioselectivity
under
mild
conditions.
full
complement
four
stereoisomers
products
could
be
readily
accessed
orthogonal
permutations
two
chiral
metal
catalysts.
work
highlights
power
for
stereodivergent
construction
that
were
otherwise
inaccessible.
Angewandte Chemie,
Год журнала:
2021,
Номер
133(41), С. 22340 - 22345
Опубликована: Июль 15, 2021
Abstract
The
Pd‐catalyzed
asymmetric
addition
reaction
of
β‐keto
acids
to
heteroatom‐substituted
allene
is
reported.
This
generates
β‐substituted
ketones
in
an
manner
through
a
branch‐selective
decarboxylative
allylation
pathway.
accommodates
various
alkoxyallenes
as
well
amidoallenes.