Angewandte Chemie,
Journal Year:
2024,
Volume and Issue:
136(25)
Published: Jan. 22, 2024
Abstract
β‐Tertiary
amino
acid
derivatives
constitute
one
of
the
most
frequently
occurring
units
in
natural
products
and
bioactive
molecules.
However,
efficient
asymmetric
synthesis
this
motif
still
remains
a
significant
challenge.
Herein,
we
disclose
cobalt‐catalyzed
enantioselective
reductive
addition
reaction
ketimine
using
α‐chloro
carbonyl
compound
as
radical
precursor,
providing
expedient
access
to
diverse
array
enantioenriched
β‐quaternary
analogues.
This
protocol
exhibits
outstanding
enantioselectivity
broad
substrate
scope
with
excellent
functional
group
tolerance.
Preliminary
mechanism
studies
rule
out
possibility
Reformatsky‐type
confirm
involvement
species
stereoselective
process.
The
synthetic
utility
has
been
demonstrated
through
rapid
assembly
iterative
oligopeptide,
showcasing
its
versatile
platform
for
late‐stage
modification
drug
candidates.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(12), P. 6944 - 6952
Published: March 15, 2023
Enantioselective
metallaphotoredox
catalysis,
which
combines
photoredox
catalysis
and
asymmetric
transition-metal
has
become
an
effective
approach
to
achieve
stereoconvergence
under
mild
conditions.
Although
many
impressive
synthetic
approaches
have
been
developed
access
central
chirality,
the
construction
of
axial
chirality
by
still
remains
underexplored.
Herein,
we
report
two
visible
light-induced
cobalt-catalyzed
reductive
couplings
biaryl
dialdehydes
synthesize
axially
chiral
aldehydes
(60
examples,
up
98%
yield,
>19:1
dr,
>99%
ee).
This
protocol
shows
good
functional
group
tolerance,
broad
substrate
scope,
excellent
diastereo-
enantioselectivity.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(14), P. 7983 - 7991
Published: March 28, 2023
Conjugate
addition
is
among
the
most
important
synthetic
protocols
for
constructing
carbon
skeletons
and
widely
used
to
synthesize
natural
products
drugs.
However,
asymmetric
catalysis
studies
have
mainly
focused
on
stereogenic
centers
arising
from
conjugate
alkenes.
Here,
we
report
first
photoinduced
cobalt-catalyzed
dynamic
kinetic
reductive
reaction
that
enables
formation
of
heterobiaryls
with
axial
chirality
(45
examples,
up
91%
yield
97%
ee).
This
method
features
mild
conditions,
good
functional-group
tolerance,
excellent
enantiomeric
control.
Significantly,
large
amounts
metal
waste
precious
catalysts
can
be
avoided
under
these
conditions.
Migration
chiral
arylcobalt
species
into
alkene
might
rate-determining
step
based
studies.
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(50), P. 23001 - 23009
Published: Dec. 8, 2022
A
new
regio-
and
stereoselective
reductive
coupling
of
alkynes
crotononitrile
has
been
developed
via
visible
light
organophotoredox
cobalt
dual
catalysis.
variety
enantioenriched
homoallylic
nitriles
bearing
a
stereodefined
trisubstituted
alkene
have
easily
synthesized
with
good
to
excellent
(up
>20:1
rr),
stereo-
(>20:1
E/Z),
enantioselectivity
98%
ee)
control
under
mild
conditions.
The
corresponding
nitrile
products
were
smoothly
converted
into
various
chiral
building
blocks.
Remarkably,
simple
organic
base
together
water
utilized
as
hydrogen
sources
in
this
photoinduced
reaction.
ACS Catalysis,
Journal Year:
2024,
Volume and Issue:
14(7), P. 4638 - 4647
Published: March 12, 2024
Axially
chiral
diaryl
ethers
make
up
a
unique
class
of
atropisomers
bearing
restricted
rotation
about
the
C–O
bond.
Methods
for
expedient
synthesis
axially
ether-based
structures
have
been
largely
underdeveloped.
Herein,
we
developed
an
efficient
metal-catalyzed
desymmetrization
strategy
to
unveil
formation
and
centrally
dual
in
high
diastereo-
enantioselectivity.
The
protocol
leverages
cobalt-catalyzed
photoreductive
enantioselective
couplings
dialdehyde
alkyne
deliver
stereogenicity,
ether
scaffold
is
equipped
with
useful
synthetic
handles
including
formyl,
hydroxyl,
allyl
groups,
as
has
demonstrated
carboxylic
acid
potential
ligand
asymmetric
catalysis.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(25)
Published: Jan. 22, 2024
β-Tertiary
amino
acid
derivatives
constitute
one
of
the
most
frequently
occurring
units
in
natural
products
and
bioactive
molecules.
However,
efficient
asymmetric
synthesis
this
motif
still
remains
a
significant
challenge.
Herein,
we
disclose
cobalt-catalyzed
enantioselective
reductive
addition
reaction
ketimine
using
α-chloro
carbonyl
compound
as
radical
precursor,
providing
expedient
access
to
diverse
array
enantioenriched
β-quaternary
analogues.
This
protocol
exhibits
outstanding
enantioselectivity
broad
substrate
scope
with
excellent
functional
group
tolerance.
Preliminary
mechanism
studies
rule
out
possibility
Reformatsky-type
confirm
involvement
species
stereoselective
process.
The
synthetic
utility
has
been
demonstrated
through
rapid
assembly
iterative
oligopeptide,
showcasing
its
versatile
platform
for
late-stage
modification
drug
candidates.
Chinese Journal of Chemistry,
Journal Year:
2023,
Volume and Issue:
41(23), P. 3253 - 3260
Published: July 20, 2023
Comprehensive
Summary
Secondary
alcohols
bearing
both
axial
and
central
chirality
comprise
attractive
biological
activity
exhibit
excellent
chiral
induction
in
asymmetric
reactions.
However,
only
very
limited
catalytic
approaches
were
developed
for
their
synthesis.
We
herein
describe
visible
light‐mediated
cobalt‐catalyzed
reductive
Grignard‐type
addition
of
aryl
iodides
with
axially
prochiral
biaryl
dialdehydes
leading
to
the
direct
construction
secondary
alcohols.
Preliminary
mechanistic
studies
indicate
that
efficient
kinetic
recognition
diastereomers
might
occur
improve
stereoselectivity,
which
open
a
new
avenue
challenging
cascade
multiple
elements.
This
protocol
features
enantio‐
diastereoselectivity,
green
mild
conditions,
simple
operation,
broad
substrate
scope,
providing
modular
platform
synthesis
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(37), P. 20152 - 20157
Published: Sept. 11, 2023
Transition-metal-catalyzed
reductive
coupling
reactions
of
alkynes
and
imines
are
attractive
methods
for
the
synthesis
chiral
allylic
amines.
Mechanistically,
these
involve
oxidative
cyclization
alkyne
imine
to
generate
a
metallacyclic
intermediate,
which
then
reacts
with
H2
or
surrogate
form
product.
As
an
alternative
this
hydrogenolysis
pathway,
here
we
show
that
transmetalation
zinc
can
occur,
forming
metallacycle
This
organozinc
product
serves
as
versatile
nucleophile
carbon-carbon
carbon-heteroatom
reactions.
Mechanistic
studies
based
on
isotopic
labeling
experiments
DFT
calculations
suggest
key
step
occurs
between
Co(II)
species
ZnCl2.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(13)
Published: Jan. 19, 2024
Abstract
In
modern
organic
chemistry,
harnessing
the
power
of
multicomponent
radical
reactions
presents
both
significant
challenges
and
extraordinary
potential.
This
article
delves
into
this
scientific
frontier
by
addressing
critical
issue
controlling
selectivity
in
such
complex
processes.
We
introduce
a
novel
approach
that
revolves
around
reversible
addition
thiyl
radicals
to
multiple
bonds,
reshaping
landscape
reactions.
The
key
lies
intricate
interplay
between
reversibility
energy
landscapes
governing
C−C
bond
formation
thiol‐yne‐ene
developed
not
only
allows
prioritize
cascade,
dominating
over
alternative
reactions,
but
also
extends
scope
coupling
products
obtained
from
alkenes
alkynes
various
structures
electron
density
distributions,
regardless
their
relative
polarity
difference,
opening
doors
more
versatile
synthetic
possibilities.
present
study,
we
provide
powerful
tool
for
atom‐economical
C−S
formation,
paving
way
efficient
synthesis
molecules.
Carrying
out
our
experimental
computational
studies,
elucidated
fundamental
mechanisms
underlying
cascades,
knowledge
can
be
broadly
applied
field
chemistry.
Chemistry - A European Journal,
Journal Year:
2023,
Volume and Issue:
29(37)
Published: April 19, 2023
M-HAT
isomerization
is
a
highly
reliable
method
to
access
thermodynamically
stable
alkenes
with
high
functional
group
tolerance.
However,
synthesis
of
heteroatom-substituted
by
reaction
still
underdeveloped.
Herein,
we
report
an
enamide
using
via
combination
cobalt
and
photoredox
catalysis.
This
tolerates
variety
groups
including
haloarenes,
heteroarenes,
free
hydroxy
groups,
non-protected
indoles,
drug
derivatives.
Furthermore,
this
can
isomerize
styrene
derivatives
in
good
yield
E/Z
selectivity.
ACS Catalysis,
Journal Year:
2024,
Volume and Issue:
14(5), P. 3369 - 3375
Published: Feb. 16, 2024
Substituted
cyclic
alcohol
is
one
of
the
pharmaceutically
essential
scaffolds.
Here,
we
report
photoredox/cobalt-catalyzed
reductive
cyclization
alkynals
using
H2O
for
catalyst
turnover.
This
method
was
applied
to
aliphatic
and
aromatic
aldehydes
five-,
six-,
seven-membered
(heterocyclic)
ring
formation
with
various
substitutions
on
alkyne
units.
H2O-added
protocol
further
developed
into
a
one-pot
transformation
from
acetals
through
in
situ
generated
aldehydes,
which
shortened
synthetic
path
reaction.
