ACS Catalysis,
Journal Year:
2022,
Volume and Issue:
12(21), P. 13411 - 13417
Published: Oct. 18, 2022
The
intermolecular
1,3-diamination
reaction
of
readily
available
alkenes
with
N-fluorobis(benzenesulfonamides)
catalyzed
by
rhodium(II)
is
reported
herein.
isomers
the
terminal
and
internal
alkenes,
even
mixtures,
all
provided
same
allylic
1,3-diamine
products
under
mild
conditions.
resulting
diaminated
can
be
derived
to
functionalized
diamines
further
generate
triamines.
Mechanistic
studies
revealed
that
compounds
a
variety
chemical
transformations
during
reactions
based
on
their
single-electron
redox
catalytic
cycle,
specifically
radical
polarity
crossover
in
direct
activation
C–H
bonds
followed
cross-coupling
alkenes.
These
results
show
potential
amination
addition
well-known
rhodium
nitrenoids.
ACS Central Science,
Journal Year:
2021,
Volume and Issue:
7(2), P. 245 - 261
Published: Feb. 2, 2021
Since
the
definition
of
"12
Principles
Green
Chemistry"
more
than
20
years
ago,
chemists
have
become
increasingly
mindful
need
to
conserve
natural
resources
and
protect
environment
through
judicious
choice
synthetic
routes
materials.
The
direct
activation
functionalization
C–H
bonds,
bypassing
intermediate
functional
group
installation
is,
in
abstracto,
step
atom
economic,
but
numerous
factors
still
hinder
sustainability
large-scale
applications.
In
this
Outlook,
we
highlight
research
areas
seeking
overcome
challenges
activation:
pursuit
abundant
metal
catalysts,
avoidance
static
directing
groups,
replacement
oxidants,
introduction
bioderived
solvents.
We
close
by
examining
progress
made
subfield
aryl
borylation
from
its
origins,
highly
efficient
precious
Ir-based
systems,
emerging
3d
catalysts.
future
growth
field
will
depend
on
industrial
uptake,
thus
urge
researchers
strive
toward
sustainable
activation.
Science,
Journal Year:
2022,
Volume and Issue:
378(6625), P. 1207 - 1213
Published: Dec. 15, 2022
Aliphatic
allylic
amines
are
found
in
a
great
variety
of
complex
and
biorelevant
molecules.
The
direct
C-H
amination
alkenes
serves
as
the
most
straightforward
method
toward
these
motifs.
However,
use
widely
available
internal
with
aliphatic
this
transformation
remains
synthetic
challenge.
In
particular,
palladium
catalysis
faces
twin
challenges
inefficient
coordination
Pd(II)
to
but
excessively
tight
therefore
inhibitory
by
basic
amines.
We
report
general
solution
problems.
developed
protocol,
contrast
classical
Pd(II/0)
scenario,
operates
through
blue
light-induced
Pd(0/I/II)
manifold
mild
aryl
bromide
oxidant.
This
open-shell
approach
also
enables
enantio-
diastereoselective
amination.
Angewandte Chemie International Edition,
Journal Year:
2021,
Volume and Issue:
60(21), P. 11779 - 11783
Published: March 4, 2021
Abstract
Direct
allylic
C−H
thiolation
is
straightforward
for
C(sp
3
)−S
bond
formation.
However,
strong
interactions
between
thiol
and
transition
metal
catalysts
lead
to
deactivation
of
the
catalytic
cycle
or
oxidation
sulfur
atom
under
oxidative
condition.
Thus,
direct
)−H
has
proved
difficult.
Represented
herein
an
exceptional
direct,
efficient,
atom‐
step‐economic
S−H
visible
light
irradiation.
Radical
trapping
experiments
electron
paramagnetic
resonance
(EPR)
spectroscopy
identified
radical
thiyl
generated
on
surface
photocatalyst
quantum
dots
(QDs).
The
C−S
formation
does
not
require
external
oxidants
initiators,
hydrogen
(H
2
)
produced
as
byproduct.
When
vinylic
was
used
instead
bond,
radical‐radical
cross‐coupling
achieved
with
liberation
H
.
Such
a
unique
transformation
opens
up
door
toward
coupling
valuable
organosulfur
chemistry.
Chemical Science,
Journal Year:
2021,
Volume and Issue:
13(4), P. 1003 - 1008
Published: Dec. 20, 2021
Selective
functionalization
of
allylic
C-H
bonds
into
other
chemical
is
among
the
most
straightforward
and
attractive,
yet
challenging
transformations.
Herein,
a
transition-metal-free
protocol
for
direct
nitrogenation,
oxygenation,
carbonation
alkenes
by
thianthrenation
was
developed.
This
operationally
simple
allows
unified
amination,
esterification,
etherification,
arylation
vinyl
thianthrenium
salts.
Notably,
reaction
furnishes
multialkyl
substituted
amines,
ammonium
salts,
sulfonyl
amides,
esters,
ethers
in
good
yields.
The
proceeds
under
mild
conditions
with
excellent
functional
group
tolerance
could
be
applied
to
late-stage
allylation
natural
products,
drug
molecules
peptides
chemoselectivity.
Nature Communications,
Journal Year:
2021,
Volume and Issue:
12(1)
Published: June 18, 2021
Abstract
Oxidative
allylic
C–H
functionalization
is
a
powerful
tool
to
streamline
organic
synthesis
as
it
minimizes
the
need
for
functional
group
activation
and
generates
alkenyl-substituted
products
amenable
further
chemical
modifications.
The
intramolecular
variants
can
be
used
construct
functionalized
ring
structures
but
remain
limited
in
scope
by
their
frequent
requirement
noble
metal
catalysts
stoichiometric
oxidants.
Here
we
report
an
oxidant-free,
electrocatalytic
approach
achieve
oxidative
amination
alkylation
employing
tailored
cobalt-salen
complexes
catalysts.
These
reactions
proceed
through
radical
mechanism
display
broad
tolerance
of
groups
alkene
substitution
patterns,
allowing
efficient
coupling
di-,
tri-
even
tetrasubstituted
alkenes
with
N-
C-nucleophiles
furnish
high-value
heterocyclic
carbocyclic
structures.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(17), P. 9448 - 9453
Published: April 13, 2023
Direct
coupling
of
unactivated
olefins
with
primary
alkylamines
is
considered
to
be
an
efficient
but
unknown
method
for
the
construction
complex
amines.
Herein
we
report
a
catalytic
intermolecular
oxidative
amination
aliphatic
amines
based
on
combination
palladium
catalyst,
bidentate
phosphine
ligand,
and
duroquinone.
A
range
secondary
allylic
were
obtained
in
good
yields
excellent
regio-
stereoselectivity.
Mechanistic
control
experiments
revealed
that
reaction
proceeds
by
C(sp3)-H
activation
nucleophilic
amination.
The
utility
protocol
further
demonstrated
late-stage
modification
streamlined
synthesis
drug
molecules.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(10)
Published: Jan. 9, 2023
Abstract
Propylene
gas
is
produced
worldwide
by
steam
cracking
on
million‐metric‐ton
scale
per
year.
It
serves
as
a
valuable
starting
material
for
π‐bond
functionalization
but
rarely
applied
in
transition
metal‐catalyzed
allylic
C−H
fine
chemical
synthesis.
Herein,
we
report
that
newly‐developed
cationic
cyclopentadienyliron
dicarbonyl
complex
allows
the
conversion
of
propylene
to
its
C−C
bond
coupling
products
under
catalytic
conditions.
This
approach
was
also
found
applicable
simple
α‐olefins
with
distinctive
branched
selectivity.
Experimental
and
computational
mechanistic
studies
supported
deprotonation
metal‐coordinated
alkene
turnover‐limiting
step
led
insights
into
multifaceted
roles
newly
designed
ligand
promoting
enhanced
reactivity
stereoselectivity.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(16)
Published: Feb. 8, 2024
Oxidative
alkene
functionalization
reactions
are
a
fundamental
class
of
complexity-building
organic
transformations.
However,
the
majority
established
approaches
rely
on
electrophilic
reagents
that
limit
diversity
groups
can
be
installed.
Recent
advances
have
new
approach
instead
relies
transformation
alkenes
into
thianthrene-derived
cationic
electrophiles.
These
linchpin
intermediates
generated
selectively
and
undergo
diverse
array
mechanistically
distinct
with
abundant
nucleophiles.
Taken
together,
this
unlocks
suite
net
oxidative
transformations
been
elusive
using
conventional
strategies.
This
Minireview
describes
these
is
organized
around
three
synthons
formally
accessible
from
via
thianthrenation:
1)
alkenyl
cations;
2)
vicinal
dications;
3)
allyl
cations.
Throughout
Minireview,
we
illustrate
how
thianthrenium
salts
address
key
limitations
endemic
to
classic
alkene-derived
electrophiles
highlight
mechanistic
origins
distinctions
wherever
possible.
