ACS Catalysis,
Год журнала:
2021,
Номер
11(11), С. 6643 - 6655
Опубликована: Май 21, 2021
We
report
details
of
the
reaction
mechanism
for
a
coupling
1,3-dienes
with
C-nucleophiles
that
was
catalyzed
by
Ni/Cu
cooperative
catalyst
system
using
Ni(cod)2
and
[Cu(CH3CN)4]PF6
in
presence
chiral
JOSIPHOS-type
bisphosphine
ligand
iPr2NEt,
providing
direct
access
to
highly
valuable
vicinal
quaternary
tertiary
stereocenters
high
enantio-
diastereoselectivity.
The
bimetallic
exhibited
broad
substrate
scope,
including
both
cyclic/acyclic
stabilized
nucleophiles
aryl-/alkyl-substituted
1,3-dienes.
elucidated
depth
isolating
characterizing
four
key
complexes
nickel
copper
conducting
deuterium
labeling
experiments,
kinetic
studies,
density
functional
theory
calculations.
turnover-limiting
step
this
is
proton-transfer
diene-coordinated
Ni
complex
6
from
cationic
Cu
8
yield
π-allyl
7
enolate
9,
respectively.
stereoselectivity
also
clarified
according
single-point
calculations
intermediates
9.
Chemical Reviews,
Год журнала:
2020,
Номер
120(24), С. 13545 - 13598
Опубликована: Дек. 10, 2020
Following
a
strong
regain
of
interest
over
the
past
20
years
in
chemistry
allenes,
this
"forgotten"
family
unsaturated
molecules
is
undergoing
renaissance.
In
context,
metal-catalyzed
hydrofunctionalization
allenes
nowadays
one
most
studied
transformations.
The
latter
great
because
it
opens
way
to
produce
selectively
functionalized
allylic
structures.
These
motifs
are
important
synthesis,
particularly
for
formation
asymmetric
centers.
Hydrofunctionalization
also
totally
atom
economical
strategy,
avoiding
generation
any
waste,
Compared
main
pathway
obtain
(aka
Tsuji-Trost
substitution),
does
not
require
prefunctionalization
starting
material
with
leaving
group.
This
review
presents
state
art
exploration
all
existing
transition
methods
allowing
selective
intermolecular
N–H,
C–H,
and
O–H
nucleophiles
or
electrophiles.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(19), С. 7285 - 7291
Опубликована: Май 10, 2021
Herein
we
describe
a
protocol
for
the
unprecedented
stereodivergent
synthesis
of
tertiary
fluoride-tethered
allenes
bearing
stereogenic
center
and
axis
via
Cu/Pd
synergistic
catalysis.
A
broad
scope
conjugated
enynes
are
coupled
with
various
α-fluoroesters
in
high
yields
diastereoselectivities
generally
>99%
ee.
In
addition,
four
stereoisomers
allene
products
ensure
precise
access
to
corresponding
fluorinated
hydrofurans
novel
axial-to-central
chirality
transfer
process.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(33), С. 13382 - 13392
Опубликована: Авг. 10, 2021
The
construction
of
carbon–heteroatom
bonds
is
one
the
most
active
areas
research
in
organic
chemistry
because
function
molecules
often
derived
from
presence
heteroatoms.
Although
considerable
advances
have
recently
been
achieved
radical-involved
catalytic
asymmetric
C–N
bond
formation,
there
has
little
progress
corresponding
C–O
bond-forming
processes.
Here,
we
describe
a
photoinduced
copper-catalyzed
cross-coupling
readily
available
oxime
esters
and
1,3-dienes
to
generate
diversely
substituted
allylic
with
high
regio-
enantioselectivity
(>75
examples;
up
95%
ee).
reaction
proceeds
at
room
temperature
under
excitation
by
purple
light-emitting
diodes
(LEDs)
features
use
single,
earth-abundant
copper-based
chiral
catalyst
as
both
photoredox
for
radical
generation
source
induction
coupling.
Combined
experimental
density
functional
theory
(DFT)
computational
studies
suggest
formation
π-allylcopper
complexes
redox-active
bifunctional
reagents
through
radical–polar
crossover
process.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(45)
Опубликована: Авг. 2, 2022
Abstract
Bimetallic
catalysis
has
emerged
as
an
efficient
strategy
for
the
development
of
new
chemical
reactions.
Importantly,
this
also
provides
a
simple
and
powerful
platform
stereodivergent
synthesis,
whereby
all
possible
stereoisomers
products
bearing
two
stereocenters
can
be
easily
prepared
from
same
set
starting
materials.
In
Minireview,
allylic
substitution,
propargylic
hydrofunctionalization,
annulation
based
on
bimetallic
been
summarized.
It
is
expected
that
more
catalytic
systems
will
developed
applied
synthesis
valuable
molecules.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(11), С. 4168 - 4173
Опубликована: Март 11, 2021
1,3-Dienes
are
readily
available
feedstocks
that
widely
used
in
the
laboratory
and
industry.
However,
potential
of
converting
1,3-dienes
into
value-added
products,
especially
chiral
has
not
yet
been
fully
exploited.
By
synergetic
photoredox/copper
catalysis,
we
achieve
first
visible-light-induced,
enantioselective
carbocyanation
by
using
carboxylic
acid
derivatives
trimethylsilyl
cyanide.
Under
mild
neutral
conditions,
a
diverse
range
allyl
cyanides
produced
generally
good
efficiency
with
high
enantioselectivity
from
bench-stable
user-safe
chemicals.
Moreover,
preliminary
results
also
confirm
this
success
can
be
expanded
to
1,3-enynes
four-component
carbonylative
1,3-enynes.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
60(42), С. 22956 - 22962
Опубликована: Авг. 18, 2021
Abstract
Kharasch–Sosnovsky
reaction
is
one
of
the
most
powerful
methods
for
allylic
oxidation
alkenes.
However,
inherent
radical
mechanism
and
use
peroxides
as
both
oxidants
oxygen
nucleophiles
render
dearth
universal
catalytic
systems
highly
enantioselective
variants
limited
scope.
Herein,
an
alternative
to
asymmetric
that
utilized
a
chiral
copper
catalyst
purple‐LED
irradiation
enable
three‐component
coupling
1,3‐dienes,
oxime
esters,
carboxylic
acids
reported.
This
protocol
features
mild
conditions,
remarkable
scope
functional
group
tolerance
evidenced
by
>80
examples
utility
in
late‐stage
modification
pharmaceuticals
natural
products.
Detailed
mechanistic
studies
provide
evidences
radical‐based
pathway.
