Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(7), С. 4142 - 4149
Опубликована: Фев. 8, 2023
Alkene
functionalization
with
a
single-atom
catalyst
(SAC)
which
merges
homogeneous
and
heterogeneous
catalysis
is
fascinating
route
to
obtain
high-value-added
molecules.
However,
C–N
bond
formation
of
alkene
SAC
still
unexplored.
Herein,
bimetal-organic
framework-derived
Co–N/C
an
atomically
dispersed
cobalt
center
reported
show
good
activity
chemoselective
aziridination/oxyamination
reactions
from
hydroxylamine,
late-stage
complex
alkenes
diversified
synthetic
transformations
the
aziridine
product
further
expand
utility
this
method.
Moreover,
system
proceeds
without
external
oxidants
exhibits
mild,
atom-economic,
recyclable
characters.
Detailed
spectroscopic
characterizations
mechanistic
studies
revealed
structure
catalytic
possible
intermediates
involved
in
mechanism
cycle.
Chemical Communications,
Год журнала:
2022,
Номер
58(72), С. 9991 - 10003
Опубликована: Янв. 1, 2022
Electrophilic
aminating
reagents
have
seen
a
renaissance
in
recent
years
as
effective
nitrogen
sources
for
the
synthesis
of
unprotected
amino
functionalities.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(37), С. 20196 - 20201
Опубликована: Сен. 6, 2023
Hydroxylamine-derived
reagents
have
enabled
versatile
nitrene
transfer
reactions
for
introducing
nitrogen-containing
functionalities
in
small-molecule
catalysis,
as
well
biocatalysis.
These
reagents,
however,
result
a
poor
atom
economy
and
stoichiometric
organic
waste.
Activating
hydroxylamine
(NH
ACS Organic & Inorganic Au,
Год журнала:
2024,
Номер
4(3), С. 287 - 300
Опубликована: Март 4, 2024
In
the
past
5
years,
hexafluoroisopropanol
(HFIP)
has
been
used
as
a
unique
solvent
or
additive
to
enable
challenging
transformations
through
substrate
activation
and
stabilization
of
reactive
intermediates.
this
Review,
we
aim
at
describing
difunctionalization
processes
which
were
unlocked
when
HFIP
was
involved.
Specifically,
focus
on
cyclizations
additions
alkenes,
alkynes,
epoxides,
carbonyls
that
introduce
wide
range
functional
groups
interest.
Abstract
Iron‐catalyzed
C−H
amination
is
emerging
as
an
attractive
and
sustainable
method
to
install
amine
functionalities
into
organic
compounds.
Amination
of
C(
sp
3
)−H
bonds
usually
mediated
by
iron‐nitrene
intermediate
via
a
Hydrogen
Atom
Abstraction/Radical
Recombination
mechanism
reminiscent
biomimetic
oxidation.
Accordingly,
this
transformation
can
be
catalyzed
engineered
iron
enzymes,
heme
nonheme
complexes
well
salts,
although
it
often
limited
intramolecular
reactions
and/or
activated
positions.
Aromatic
2
addition
electrophilic
nitrenes
or
protonated
N‐radical
intermediates
(produced
with
Fe
catalysts)
aromatic
systems.
Again,
high
selectivity
obtained
(pseudo)
reactions.
From
mechanistic
perspective,
several
nitrene
have
been
isolated
characterized
over
the
years
in
different
ligand
scaffolds
oxidation
states.
Structure‐activity
correlations
drawn
only
few
cases
point
key
role
spin
density
on
state.
This
review
describes
state
art
for
homogeneous
focusing
last
5
(2019–2023)
from
mechanism‐driven
catalyst
design
perspective.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(5), С. 2884 - 2900
Опубликована: Янв. 25, 2023
The
involvement
of
planar
carbocation
intermediates
is
generally
considered
undesirable
in
asymmetric
catalysis
due
to
the
difficulty
gaining
facial
control
and
their
intrinsic
stability
issues.
Recently,
suitably
designed
chiral
catalyst(s)
have
enabled
a
guided
approach
nucleophiles
one
prochiral
faces
carbocations
affording
high
enantiocontrol.
Herein,
we
present
vital
mechanistic
insights
from
our
comprehensive
density
functional
theory
(B3LYP-D3)
study
on
Ir-phosphoramidite-catalyzed
reductive
deoxygenation
racemic
tertiary
α-substituted
allenylic
alcohols.
catalytic
transformation
relies
synergistic
action
phosphoramidite-modified
Ir
catalyst
Bi(OTf)3,
first
leading
formation
an
Ir-π-allenyl
intermediate
through
turn-over-determining
SN1
ionization,
followed
by
face-selective
hydride
transfer
Hantzsch
ester
analogue
yield
enantioenriched
product.
Bi(OTf)3
was
found
promote
significant
number
ionic
interactions
as
well
noncovalent
(NCIs)
with
substrates
(allenylic
alcohol
ester),
thus
providing
access
lower
energy
route
compared
pathways
devoid
Bi(OTf)3.
In
nucleophilic
addition,
induction
depend
efficacy
such
key
NCIs.
curious
case
reversal
enantioselectivity,
when
α-substituent
allenyl
changed
methyl
cyclopropyl,
identified
originate
change
mechanism
enantioconvergent
pathway
(α-methyl)
dynamic
kinetic
(α-cyclopropyl).
These
molecular
could
lead
newer
strategies
tame
enantioselective
reactions
using
suitable
combinations
catalysts
additives.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(52)
Опубликована: Ноя. 15, 2023
The
utilization
of
a
single-atom
catalyst
to
break
C-C
bonds
merges
the
merits
homogeneous
and
heterogeneous
catalysis
presents
an
intriguing
pathway
for
obtaining
high-value-added
products.
Herein,
mild,
selective,
sustainable
oxidative
cleavage
alkene
form
oxime
ether
or
nitrile
was
achieved
by
using
atomically
dispersed
cobalt
hydroxylamine.
Diversified
substrate
patterns,
including
symmetrical
unsymmetrical
alkenes,
di-
tri-substituted
late-stage
functionalization
complex
alkenes
were
demonstrated.
reaction
successfully
scaled
up
demonstrated
good
performance
in
recycling
experiments.
hot
filtration
test,
poisoning
radical
scavenger
experiment,
time
kinetics,
studies
on
intermediate
collectively
pointed
mechanism
with
cobalt/acid/O2
promoted
bond
as
key
step.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
62(9)
Опубликована: Дек. 21, 2022
β-Arylethylamines
are
prevalent
structural
motifs
in
molecules
exhibiting
biological
activity.
Here
we
report
a
sequential
one-pot
protocol
for
the
1,2-aminoarylation
of
alkenes
with
hydroxylammonium
triflate
salts
and
(hetero)arenes.
Unlike
existing
methods,
this
reaction
provides
direct
entry
to
unprotected
β-arylethylamines
remarkable
functional
group
tolerance,
allowing
key
drug-oriented
groups
be
installed
two-step
process.
The
use
hexafluoroisopropanol
as
solvent
combination
an
iron(II)
catalyst
proved
essential
reaching
high-value
nitrogen-containing
molecules.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(36), С. 24863 - 24870
Опубликована: Авг. 28, 2024
Primary
amines
are
privileged
molecules
in
drug
development.
Yet,
there
is
a
noticeable
scarcity
of
methods
for
directly
introducing
primary
amine
group
into
the
ubiquitous
C(sp
