Organic & Biomolecular Chemistry,
Journal Year:
2022,
Volume and Issue:
21(10), P. 2046 - 2058
Published: Nov. 18, 2022
This
review
describes
several
key
activation
methods
for
Langlois'
reagent
in
the
difunctionalization
of
alkenes
and
could
stimulate
interest
readers
promoting
wider
development
application
reagent.
Accounts of Chemical Research,
Journal Year:
2022,
Volume and Issue:
55(20), P. 3043 - 3056
Published: Sept. 27, 2022
ConspectusThe
radical-mediated
C–H
functionalization
of
pyridines
has
attracted
considerable
attention
as
a
powerful
tool
in
synthetic
chemistry
for
the
direct
bonds
pyridine
scaffold.
Classically,
methods
functionalized
often
involve
Minisci-type
reactions
under
strongly
acidic
conditions.
However,
site-selective
unbiased
systems
been
long-standing
challenge
because
scaffold
contains
multiple
competing
reaction
sites
(C2
vs
C4)
to
intercept
free
radicals.
Therefore,
prefunctionalization
is
required
avoid
issues
observed
with
formation
mixture
regioisomers
and
overalkylated
side
products.Recently,
N-functionalized
pyridinium
salts
have
attracting
organic
promising
radical
precursors
surrogates.
The
notable
advantage
lies
their
ability
enhance
reactivity
selectivity
synthetically
useful
acid-free
This
approach
enables
exquisite
regiocontrol
nonclassical
at
C2
C4
positions
mild
conditions,
which
are
suitable
late-stage
bioactive
molecules
greater
complexity
diversity.
Over
past
five
years,
variety
fascinating
applications
developed
using
various
types
visible
light
In
addition,
new
platform
alkene
difunctionalization
appropriately
designed
N-substituted
bifunctional
reagents
reported,
offering
an
innovative
assembly
process
complex
architectures.
Intriguingly,
strategies
involving
light-absorbing
electron
donor–acceptor
(EDA)
complexes
between
electron-rich
donors
further
open
up
photocatalyst-free
Furthermore,
we
enantioselective
afford
enantioenriched
bearing
through
single-electron
N-heterocyclic
carbene
(NHC)
catalysis.Herein,
provide
broad
overview
our
recent
contributions
development
summarize
cornerstones
that
successfully
employ
these
major
advances
field
systematically
categorized
on
basis
pyridines'
N-substituent,
N–X
(X
=
O,
N,
C,
SO2CF3),
its
patterns.
identification
activation
modes
mechanistic
aspects
discussed
by
providing
representative
each
paradigm.
We
hope
this
Account
will
inspire
interest
continued
innovation
exploration
transformations.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(30), P. 16630 - 16641
Published: July 24, 2023
β-(Hetero)arylethylamines
are
privileged
structural
motifs
found
in
many
high-value
organic
molecules,
including
pharmaceuticals
and
natural
products.
To
construct
these
important
molecular
skeletons,
previous
methods
mainly
achieved
by
amino(hetero)arylation
reaction
with
the
aid
of
transition
metals
preactivated
substrates.
Herein,
we
report
a
metal-free
photoinduced
intermolecular
for
single-step
installation
both
(hetero)aryl
iminyl
groups
across
alkenes
an
efficient
regioselective
manner.
This
method
shows
broad
scope
(up
to
124
examples)
excellent
tolerance
various
olefins─from
simplest
ethylene
complex
multisubstituted
can
all
participate
reaction.
Furthermore,
aminosulfonylation
be
also
conducted
presence
sodium
bisulfite
as
SO2
source.
Advanced Synthesis & Catalysis,
Journal Year:
2023,
Volume and Issue:
365(10), P. 1538 - 1564
Published: March 6, 2023
Abstract
Quaternary
pyridinium
compounds
are
valuable
intermediates
in
organic
synthesis,
which
have
gained
immense
popularity
the
synthetic
community.
The
application
of
transition
metal
or
photoredox
catalysis
transforming
quaternary
into
various
C−C
and
C−X
bonds
is
well
established.
A
majority
these
methods
require
high
temperatures,
expansive
catalysts,
delicate
conditions
for
successful
execution.
On
other
hand,
use
metal‐free
photocatalysis‐free
strategies
constructing
using
derivatives
has
been
sought‐after.
In
this
context,
electron‐donor‐acceptor
(EDA)‐complex
reactions
emerged
as
a
state‐of‐the‐art
methodology,
do
not
any
photocatalyst
their
EDA‐complex
photochemistry
takes
advantage
electron‐acceptor
ability
derivatives,
can
quickly
generate
radical
precursor
via
deaminative
process.
These
newly
generated
useful
several
transformations.
We
hereby,
review,
discuss
an
area
major
progress
mediated
involving
with
mechanism,
substrate
scope,
limitations.
magnified
image
The Journal of Organic Chemistry,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 23, 2025
gem-Difluorohomoallyl
amines,
an
important
class
of
gem-difluoroalkenes,
are
prevalent
moieties
in
many
bioactive
compounds.
However,
limited
methods
suitable
for
the
synthesis
this
type
compound
containing
secondary
amines.
Here,
we
display
a
photocatalytic
multicomponent
protocol
gem-difluoroalkenes
which
makes
use
readily
available
materials:
arylamines,
alkyl
aldehydes,
and
α-trifluoromethyl
alkenes.
Moreover,
ketones
amines
also
substrates.
Preliminary
mechanistic
experiments
indicate
that
key
α-amino
radical
was
involved,
generated
from
reduction
situ-formed
imines
(or
iminium
ions)
by
reduced
photocatalyst.
Subsequent
addition
to
alkenes
β-F
elimination
deliver
desired
products.
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(44)
Published: Sept. 9, 2022
A
metal-free
photosensitized
protocol
for
regioselective
diamination
of
alkene
feedstocks
over
a
single
step
was
developed
based
on
the
rationally
designed
bifunctional
reagent,
thus
affording
range
differentially
protected
1,2-diamines
in
moderate
to
high
yields.
Mechanistic
studies
reveal
that
reaction
is
initiated
with
triplet-triplet
energy
transfer
between
thioxanthone
catalyst
and
followed
by
fragmentation
simultaneously
generate
long-lived
iminyl
radical
transient
amidyl
radical.
The
excellent
regioselectivity
presumably
stems
from
large
reactivity
difference
two
different
N-centered
species.
This
characterized
regioselectivity,
broad
functional
group
tolerance,
mild
conditions,
which
would
enrich
diversity
versatility
facilitate
diversity-oriented
synthesis
1,2-diamine-containing
complex
molecule
scaffolds.
Chinese Journal of Chemistry,
Journal Year:
2023,
Volume and Issue:
41(16), P. 1921 - 1930
Published: April 7, 2023
Comprehensive
Summary
The
radical‐mediated
reductive
functionalization
of
aryl
halides
has
been
extensively
studied.
However,
the
related
intermolecular
1,2‐diarylation
alkenes,
using
as
radical
sources,
remains
unexplored.
Herein,
a
new
electrophotocatalytic
alkenes
is
reported
and
cyanoaromatics
to
produce
polyarylated
alkanes.
Using
synergistic
cathodic
reduction
visible‐light
photoredox
catalysis,
various
electron‐rich
electron‐deficient
are
combined
with
characterize
broad
substrate
scope,
excellent
functional
group
compatibility,
selectivity
this
reaction.
Mechanistic
investigations
reveal
that
reaction
may
proceed
via
process
initiated
by
generation
radicals
from
terminated
radical‐radical
coupling
cyanoaromatic
anions.
Organic Letters,
Journal Year:
2023,
Volume and Issue:
25(10), P. 1742 - 1747
Published: March 8, 2023
A
new
class
of
iminosulfonylation
reagents
were
developed
and
extensively
used
in
the
1,2-iminosulfonylation
various
olefins.
Olefins
containing
bioactive
molecules,
such
as
indomethacin,
gemfibrozil,
clofibrate,
fenbufen,
afforded
desired
products
synthetically
useful
yields.
Furthermore,
first
remote
1,6-iminosulfonylation
alkenes
was
realized
by
using
oxime
ester
bifunctionalization
reagents.
Overall,
more
than
40
structurally
diverse
β-imine
sulfones
obtained
moderate
to
excellent
Organic Letters,
Journal Year:
2023,
Volume and Issue:
25(13), P. 2349 - 2354
Published: March 27, 2023
An
organo-photocatalytic
sulfonylimination
of
alkenes
was
developed
by
employing
readily
available
N-sulfonyl
ketimines
as
bifunctional
reagents.
This
transformation,
featuring
prominent
functional
group
tolerance,
provides
a
direct
and
atom-economic
approach
for
the
synthesis
valuable
β-amino
sulfone
derivatives
single
regioisomer.
In
addition
to
terminal
alkenes,
internal
participate
in
this
reaction
with
high
diastereoselectivity.
N-Sulfonyl
aryl
or
alkyl
substituents
were
found
be
compatible
condition.
method
could
applied
late-stage
modifications
drugs.
Additionally,
formal
insertion
alkene
into
cyclic
sulfonyl
imine
observed,
affording
ring
expansion
product.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(43), P. 23814 - 23823
Published: Oct. 18, 2023
Radical
remote
1,n-difunctionalization
reactions
(n
>
2)
of
alkenes
are
powerful
tools
to
efficiently
introduce
functional
groups
with
selected
distances
into
target
molecules.
Among
these
reactions,
1,5-difunctionalizations
an
important
subclass,
leading
sought-after
scaffolds,
but
typically
suffer
from
tailored
starting
materials
and
strict
limitations
for
the
formed
group
in
2-position.
Seeking
address
issues
make
radical
more
applicable,
we
report
a
novel
three-component
1,2,5-trifunctionalization
reaction
between
imine-based
bifunctional
reagents
two
distinct
alkenes,
driven
by
visible
light
energy
transfer-catalysis.
Key
achieving
this
selective
one-step
installation
three
different
via
choreographed
formation
four
bonds
was
utilization
1,2-boron
shift
rigorous
capitalization
polarities
stabilities.
Thorough
mechanistic
studies
were
carried
out,
synthetic
utility
obtained
products
demonstrated
various
downstream
modifications.
Notably,
addition
functionalization
individual
groups,
their
interplay
gave
rise
unique
array
cyclic
products.