Asian Journal of Organic Chemistry,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 29, 2024
Abstract
Asymmetric
hydrogenation
of
enol
ethers
has
emerged
as
a
valuable
and
environmentally
friendly
method
for
the
preparation
optically
active
cyclic
acyclic
ethers,
some
which
have
demonstrated
substantial
potential
application
in
synthesis
compounds
total
natural
products.
Over
past
few
decades,
significant
attention
been
devoted
to
use
transition‐metal
catalysts,
particularly
those
containing
chiral
phosphine‐phosphine,
phosphine‐amine,
or
carbene
ligands,
unfunctionalized
ethers.
In
parallel,
frustrated
Lewis
pair
catalysts
also
successfully
applied
this
transformation,
enabling
efficient
production
various
This
review
highlights
momentum
most
notable
advances
enantioselective
(with
only
alkyl
aryl
substituents
on
vinyl
group).
Owing
ubiquitous
industrial
interest,
utility
related
derivatives
is
included.
Abstract
Asymmetric
sequential
hydrogenations
of
α
‐methylene
γ
‐
or
δ
‐keto
carboxylic
acids
are
established
in
one‐pot
using
a
bimetallic
Ru/Ru
catalyst
system,
achieving
the
stereodivergent
synthesis
all
four
stereoisomers
both
chiral
and
‐lactones
with
two
non‐vicinal
carbon
stereocenters
high
yields
(up
to
99%)
excellent
stereoselectivities
>99%
ee
>20:1
dr).
The
compatibility
Ru
systems
is
investigated
detail,
it
found
that
basicity
reaction
system
plays
key
role
hydrogenation
processes.
protocol
can
be
performed
on
gram‐scale
low
loading
11000
S/C)
resulting
products
allow
for
many
transformations,
particularly
several
intermediates
useful
preparation
drugs
natural
products.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 27, 2025
The
absolute
and
relative
configurations
of
bioactive
chiral
molecules
are
typically
relevant
to
their
biological
properties.
It
is
thus
highly
important
desirable
construct
all
possible
stereoisomers
a
lead
candidate
or
given
natural
compound.
Synergistic
dual
catalysis
has
been
recognized
as
reliable
synthetic
strategy
for
variety
predictable
stereodivergent
transformations.
Despite
the
impressive
progress
made
in
this
field,
carbon-carbon
bond-formation
reactions
involving
stabilized
nucleophiles
remain
elusive.
Herein,
we
report
an
iridium-
magnesium-catalyzed
one-pot
sequential
allylic
alkylation/nucleophilic
alkylation
cascade
process
synthesis
four
3,3'-disubstituted
oxindoles
through
three-component
reaction.
A
diverse
array
products
readily
prepared
with
high
functional
group
compatibility
good
yields
excellent
diastereo-
enantioselectivities.
Subsequently,
total
spirooxindole
alkaloid
trigolutes
B
D
accomplished
concise
unified
route
using
same
set
starting
materials.
The
stereodivergent
synthesis
of
δ-lactones,
which
are
prevalent
in
natural
product
frameworks,
from
simple
starting
materials
via
a
single
transformation
remains
significant
challenge.
Herein,
we
report
an
enantio-
and
diastereodivergent
cascade
reaction
for
the
modular
chiral
δ-lactones
bearing
two
nonadjacent
quaternary
tertiary
carbon
stereocenters.
This
approach
employs
bimetallic
Ru/Cu
relay
catalysis
between
allylic
alcohols
azaaryl
acetates.
method
integrates
Ru-catalyzed
asymmetric
borrowing
hydrogen
reaction,
Cu-catalyzed
Michael
addition,
rapid
lactonization
into
one-pot
process,
with
all
catalysts
substrates
introduced
at
outset.
By
orthogonal
permutation
metal
catalysts,
precise
control
over
relative
absolute
configurations
newly
formed
stereocenters
is
achieved,
allowing
selective
access
to
stereoisomers
δ-lactone
products
predictable
efficient
manner.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 15, 2025
Consecutive
asymmetric
hydrogenation
offers
a
direct
and
convenient
approach
to
synthesizing
complex
C(sp3)-enriched
products
with
multiple
chirality.
Herein,
we
report
an
synthesis
of
chiral
1,2,3,4-tetrahydroquinolines
(THQs)
tetrahydroquinoxalines
bearing
both
endo-
exocyclic
vicinal
chirality
through
the
consecutive
transfer
easily
accessible
C2-acylated
quinolines
quinoxalines.
The
method
features
mild
conditions,
easy
operation,
broad
substrate
scope
(42
examples),
excellent
control
(generally
>90%
ee
20/1
dr).
key
success
is
use
water-soluble
aminobenzimidazole
Ir
catalyst.
Mechanistic
experiments
support
that
reaction
involves
sequential
reduction
carbonyl
group
then
quinoline
core,
each
step
dominated
by
Remarkably,
diastereodivergent
all
four
stereoisomers
THQ
has
been
successfully
implemented.
Organic Letters,
Год журнала:
2024,
Номер
26(27), С. 5850 - 5855
Опубликована: Июль 1, 2024
The
transition-metal
catalyzed
asymmetric
hydrogenation
of
unfunctionalized
alkenes
is
challenging.
Herein,
we
report
an
efficient
iridium-catalyzed
cycloalkenes,
delivering
chiral
2-aryl
tetralins
in
excellent
yields
and
with
moderate
to
enantioselectivities.
reaction
can
be
performed
on
a
gram-scale
low
catalyst
loading
(S/C
=
1000),
the
reduced
product
was
obtained
without
erosion
enantioselectivity.
Deuterium
experiments
indicated
that
C═C
bond
substrate
hydrogenated
directly
isomerization.
