ACS Catalysis,
Год журнала:
2021,
Номер
11(14), С. 8766 - 8773
Опубликована: Июль 2, 2021
Here,
we
report
an
enantioselective
nickel-hydride
catalyzed
hydroalkylation
of
readily
accessible
β-alkyl-α,β-unsaturated
amides
to
form
structurally
diverse
β-chiral
amides.
This
process
was
proposed
proceed
through
enantiodifferentiating
syn-hydrometalation
nickel
hydride,
forming
chiral
alkylnickel
at
the
β-position
in
which
regioselectivity
is
different
from
that
with
copper
hydride.
regio-reversed
hydronickellation
provides
a
complementary
approach
access
enantioenriched
β-functionalization
stereocenter
β-position.
ACS Catalysis,
Год журнала:
2021,
Номер
11(21), С. 13567 - 13574
Опубликована: Окт. 25, 2021
The
enantio-
and
stereoselective
synthesis
of
stereodefined
alkenes,
especially
the
functionalized
Z-isomer
with
an
allylic
stereogenic
center,
remains
a
great
challenge.
We
herein
report
enantioselective
benzylic
C(sp3)–H
alkenylation
simple
alkylarenes
vinyl
bromides
via
photoinduced
nickel
catalysis,
which
allows
for
stereodivergent
both
enantioenriched
Z-
E-alkenes
bearing
aryl-substituted,
tertiary
centers.
Interestingly,
tunable
Z/E-selectivity
is
achieved
by
energy
transfer
catalysis
judicious
choice
photocatalyst
counteranion.
This
versatile
strategy
features
starting
materials,
mild
reaction
conditions,
broad
substrate
scope,
divergent
E-selectivity,
high
enantioselectivities.
Moreover,
formal
asymmetric
alkylation
can
also
be
one-pot
alkenylation/reduction
sequence,
providing
complementary
to
address
notoriously
challenging
stereochemical
control
in
C(sp3)–C(sp3)
bond
construction.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(31)
Опубликована: Май 25, 2022
Regiodivergent
alkene
functionalization
that
produces
either
regioisomer
starting
from
the
same
raw
materials
is
desirable.
Herein,
we
report
a
nickel-catalyzed
switchable
site-selective
hydroalkylation.
The
selection
of
reaction
temperatures
leads
to
protocols
provide
regiodivergent
hydroalkylated
products
single
substrate.
This
protocol
allows
convenient
synthesis
α-
and
β-branched
protected
amines,
both
which
are
important
fields
pharmaceutical
chemistry
biochemistry.
In
addition,
enantioenriched
alkylamines
can
be
accessed
in
catalytic
asymmetric
variant.
Preliminary
mechanistic
studies
indicate
formation
more
stable
nickelacycle
provides
driving
force
migration.
thermodynamic
kinetic
properties
different
reduction
elimination
intermediates
responsible
for
site-selectivity.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
60(15), С. 8321 - 8328
Опубликована: Янв. 19, 2021
Abstract
Depending
on
the
reactant
property
and
reaction
mechanism,
one
major
regioisomer
can
be
favored
in
a
that
involves
multiple
active
sites.
Herein,
an
orthogonal
regulation
of
nucleophilic
electrophilic
sites
regiodivergent
hydroamination
isoprene
with
indazoles
is
demonstrated.
Under
Pd‐hydride
catalysis,
1,2‐
or
4,3‐insertion
pathway
respect
to
could
controlled
by
choice
ligands.
In
terms
indazoles,
occurs
at
either
N
1
‐
2
‐position
governed
acid
co‐catalysts.
Preliminary
experimental
studies
have
been
performed
rationalize
mechanism
regioselectivity.
This
study
not
only
contributes
practical
tool
for
selective
functionalization
isoprene,
but
also
provides
guide
manipulate
regioselectivity
‐functionalization
indazoles.
ACS Catalysis,
Год журнала:
2021,
Номер
11(14), С. 8766 - 8773
Опубликована: Июль 2, 2021
Here,
we
report
an
enantioselective
nickel-hydride
catalyzed
hydroalkylation
of
readily
accessible
β-alkyl-α,β-unsaturated
amides
to
form
structurally
diverse
β-chiral
amides.
This
process
was
proposed
proceed
through
enantiodifferentiating
syn-hydrometalation
nickel
hydride,
forming
chiral
alkylnickel
at
the
β-position
in
which
regioselectivity
is
different
from
that
with
copper
hydride.
regio-reversed
hydronickellation
provides
a
complementary
approach
access
enantioenriched
β-functionalization
stereocenter
β-position.
