Synthesis,
Journal Year:
2022,
Volume and Issue:
55(06), P. 877 - 891
Published: Oct. 7, 2022
Abstract
A
new
protocol
for
the
direct
transformation
of
secondary
amides
(N-acyl-o-xenylamines)
to
phenanthridines
under
mild
conditions
is
reported.
The
method
features
trifluoromethanesulfonic
anhydride
(Tf2O)/2-fluoropyridine
as
efficient
amide
activation
system
and
MeCN
or
CH2Cl2
solvent.
For
some
substrates,
participated
in
reaction,
which
affords
a
access
polysubstituted
quinazolines.
By
employing
Tf2O/2,4,6-tri-tert-butylpyrimidine
(TTBP)
combination,
was
extended
an
N-formyl-o-xenylamine,
represents
recalcitrant
substrate
type
dehydrative
cyclization
reaction.
More
importantly,
one-pot
established
divergent
synthesis
four
types
phenanthridinoids
from
o-xenylamines,
both
tert-N-formyl-o-xenylamine
phenanthridinium
salt
key
versatile
intermediates.
investigation
has
resulted
one
shortest
most
total
syntheses
three
natural
products
trisphaeridine,
5,6-dihydrobicolorine,
N-methylcrinasiadine,
formal
other
ones:
3-hydroxytrisphaeridine,
bicolorine,
zephycandidine
A.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(13), P. 9045 - 9062
Published: March 15, 2024
Methods
for
the
synthesis
of
α-branched
alkylamines
are
important
due
to
their
ubiquity
in
biologically
active
molecules.
Despite
development
many
methods
amine
preparation,
C(sp3)-rich
nitrogen-containing
compounds
continue
pose
challenges
synthesis.
While
carbonyl
reductive
amination
(CRA)
between
ketones
and
is
cornerstone
method
alkylamine
synthesis,
it
sometimes
limited
by
sterically
demanding
condensation
step
dialkyl
amines
more
restricted
availability
compared
aldehydes.
We
recently
reported
a
"higher-order"
variant
this
transformation,
alkylative
(CAA),
which
utilized
halogen
atom
transfer
(XAT)-mediated
radical
mechanism,
enabling
streamlined
complex
alkylamines.
efficacy
visible-light-driven
approach,
displayed
scalability
issues,
competitive
was
problem
certain
substrate
classes,
limiting
applicability.
Here,
we
report
change
reaction
regime
that
expands
CAA
platform
through
realization
an
extremely
broad
zinc-mediated
reaction.
This
new
strategy
enabled
elimination
CRA,
simplified
purification,
improved
scope.
Furthermore,
harnessed
carboxylic
acid
derivatives
as
alkyl
donors
facilitated
α-trialkyl
tertiary
amines,
cannot
be
accessed
via
CRA.
Zn-mediated
can
carried
out
at
variety
scales,
from
10
μmol
setup
microtiter
plates
high-throughput
experimentation,
gram-scale
medicinally-relevant
compounds.
believe
transformation
enables
robust,
efficient,
economical
access
provides
viable
alternative
current
benchmark
methods.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(28), P. 19286 - 19294
Published: July 3, 2024
As
one
of
the
most
powerful
trifluoromethylation
reagents,
(trifluoromethyl)trimethylsilane
(TMSCF3)
has
been
widely
used
for
synthesis
fluorine-containing
molecules.
However,
to
best
our
knowledge,
simultaneous
incorporation
both
TMS-
and
CF3-
groups
this
reagent
onto
same
carbon
products
not
realized.
Herein,
we
report
an
unprecedented
SmI2/Sm
promoted
deoxygenative
difunctionalization
amides
with
TMSCF3,
in
which
silyl
trifluoromethyl
are
incorporated
into
final
product,
yielding
α-silyl-α-trifluoromethyl
amines
high
efficiency.
Notably,
group
could
be
further
transformed
other
functional
groups,
providing
a
new
method
α-quaternary
α-CF3-amines.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(12), P. 2483 - 2488
Published: March 15, 2024
An
enantioselective
deoxygenative
functionalization
of
secondary
amides
with
vinylpridines
is
developed
by
merging
relay
iridium
catalysis
and
cooperative
photoredox-chiral
Brønsted
acid
catalysis,
affording
a
series
valuable
chiral
amines
in
moderate
to
good
yields
enantioselectivities.
The
intriguing
multiple
catalytic
system
invoking
triple-catalysis
was
found
be
the
key
success
current
reactions,
which
may
stimulate
further
development
methodologies
for
asymmetric
transformations
amides.
Nature Communications,
Journal Year:
2025,
Volume and Issue:
16(1)
Published: Jan. 22, 2025
Abstract
Secondary
amines
are
vital
functional
groups
in
pharmaceuticals,
agrochemicals,
and
natural
products,
necessitating
efficient
synthetic
methods.
Traditional
approaches,
including
N
-monoalkylation
reductive
amination,
suffer
from
limitations
such
as
poor
chemoselectivity
complexity.
Herein,
we
present
a
streamlined
deoxygenative
photochemical
alkylation
of
secondary
amides,
enabling
the
synthesis
α-branched
amines.
Our
method
leverages
triflic
anhydride-mediated
semi-reduction
amides
to
imines,
followed
by
radical
step.
This
approach
broadens
utility
facilitating
late-stage
modifications
drug-like
molecules
saturated
-substituted
heterocycles.
The
pivotal
role
flow
technology
developing
scalable
robust
process
underscores
practicality
this
method,
significantly
expanding
organic
chemist’s
toolbox
for
complex
amine
synthesis.
The Journal of Organic Chemistry,
Journal Year:
2022,
Volume and Issue:
88(1), P. 594 - 601
Published: Dec. 15, 2022
While
metal
carbene-mediated
Si–H
insertion
reactions
have
become
a
powerful
strategy
to
build
new
C–Si
bonds,
the
utilization
of
α-aminocarbene
intermediates
generated
from
readily
available
precursors
in
reaction
remains
longstanding
challenge.
Herein,
we
develop
practical
and
general
synthesize
α-aminosilanes
through
deoxygenative
cross-coupling
amides
silanes
mediated
by
Sm/SmI2.
Given
simplicity
versatility,
this
methodology
represents
fascinating
example
for
effective
inert
as
organic
synthesis.
Chemistry - A European Journal,
Journal Year:
2023,
Volume and Issue:
29(35)
Published: April 19, 2023
One
of
the
most
challenging
tasks
in
organic
synthesis
is
to
develop
novel
methodologies
for
rapid
construction
complex
molecules
starting
from
easily
available
yet
inert
raw
materials.
In
this
context,
multi-catalysis
strategies
have
attracted
great
attention
discovery
new
reactivity
profiles
that
may
allow
access
many
difficult
or
unattainable
transformations.
So
far
deoxygenative
functionalization
ubiquitous
amides
usually
achieved
by
nucleophilic
attack
on
imine
iminium
ion
intermediate
formed
via
activation
C=O
bond,
and
these
reagents
were
often
confined
C-based
nucleophiles,
which
largely
limited
diversity
resultant
amines.
Herein,
we
disclose
a
combined
strategy
relay
cooperative
catalysis
with
triple
iridium-photoredox-organocatalysis
system
achieve
an
unprecedented
reductive
boration
amides,
affording
valuable
α-amino
boron
products
are
viable
building
blocks.
transformation,
Ir-catalyzed
semi-reduction
successfully
incorporated
photo-organic
catalyzed
boryl
radical
addition,
thus
delivering
corresponding
α-boryl
amines
high
efficiency.
Green Chemistry,
Journal Year:
2023,
Volume and Issue:
25(22), P. 9080 - 9085
Published: Jan. 1, 2023
A
deoxygenative
arylation
of
amides
using
aromatic
nitriles
via
merging
Ir-catalyzed
amide
reduction
with
electrochemistry
has
been
achieved,
which
may
provide
an
alternative
strategy
for
access
to
value-added
amines
from
inert
amides.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
63(6)
Published: Dec. 13, 2023
A
reductive
(3+2)
annulation
of
lactams
through
iridium-catalyzed
hydrosilylation
and
photoredox
coupling
with
α-bromoacetic
acid
was
developed.
The
the
lactam
carbonyl
group
subsequent
elimination
provide
a
transient
cyclic
enamine,
which
undergoes
in
one-pot
process.
developed
conditions
show
high
functional-group
tolerance
N,O-acetals
containing
quaternary
carbon
center.
resulting
undergo
variety
acid-mediated
nucleophilic
addition
reactions
via
iminium
ions
to
give
substituted
amines.
sequence
including
successfully
applied
four-step
total
synthesis
(±)-eburnamonine.
