Advanced Synthesis & Catalysis,
Journal Year:
2017,
Volume and Issue:
359(24), P. 4300 - 4304
Published: Oct. 3, 2017
Abstract
A
Bronsted
acid
promoted
three‐component
synthesis
of
substituted
thieno[2,3‐
b
]indole
has
been
developed
starting
from
indoles,
alkenes
or
alkynes,
and
sulfur
powder.
N
,
‐Dimethylformamide
plays
an
important
role
to
convert
the
materials
into
fused
products.
Various
functional
groups
attached
substrates
were
well
tolerated
afford
corresponding
products
in
moderate
good
yields
under
very
simple
reaction
conditions.
magnified
image
Organic & Biomolecular Chemistry,
Journal Year:
2015,
Volume and Issue:
14(5), P. 1519 - 1530
Published: Dec. 17, 2015
O-Acyl
oximes
are
versatile
building
blocks
being
widely
applied
in
organic
synthesis,
especially
for
N-heterocycle
construction
under
transition
metal
catalysis.
In
the
last
decade,
aza-Heck
cyclization
using
has
been
progressing
preparation
of
functionalized
pyrrolines,
and
instead
Pd
catalysis,
copper-based
catalytic
systems
were
found
to
work
well
some
cases.
as
oxidizing
directing
groups
have
attracted
intensive
attention
metal-mediated
C-H
activation
reactions,
which
avoid
use
external
oxidants
feature
advantages
including
mild
reaction
conditions,
higher
levels
reactivities,
chemo-selectivities,
etc.
Moreover,
α
C(sp(3))-H
functionalization
O-acyl
subsequent
annulations
provide
a
lot
opportunities
novel
synthesis.
These
transformations
certain
advantages:
diversified
poly-functionalized
products,
easy
handling
serving
an
internal
oxidant
oxidants,
so
forth.
Chemical Society Reviews,
Journal Year:
2021,
Volume and Issue:
50(14), P. 8067 - 8101
Published: Jan. 1, 2021
Molecular
oxygen
as
a
green,
inexpensive
oxidant
and
source
has
displayed
lots
of
advantages
compared
to
other
oxidants.
This
review
introduces
the
recent
advances
radical
processes
in
molecular
oxygen-mediated
oxygenation
reactions.
ACS Catalysis,
Journal Year:
2019,
Volume and Issue:
10(1), P. 154 - 159
Published: Nov. 27, 2019
Radical
addition
is
a
robust
tool
for
bond
formation.
While
ketyl
radical
reactivity
of
aldehydes
by
photoredox
has
been
well-established,
herein,
we
have
now
revealed
pathway
umpolung
with
or
without
external
reductant.
Hence,
the
reductive
alkylations
and
challenging
benzylations
nitrogen
heteroarenes
(i.e.,
Minisci
reactions)
are
enabled
bromide-promoted
visible
light-mediated
photocatalysis.
The
present
protocol
offers
mild,
viable
method
late-stage
transition-metal-free
biologically
active
nitrogen-heteroarene
molecules.
Mechanistic
studies
indicative
bromide-initiated
acyl
mechanism
in
absence
Organic Letters,
Journal Year:
2016,
Volume and Issue:
18(20), P. 5384 - 5387
Published: Oct. 10, 2016
An
efficient
indole-to-carbazole
strategy
has
been
developed
under
metal-free
conditions.
This
carbazole
formation
was
highly
promoted
by
NH4I
with
high
regioselectivity
through
formal
[2
+
2
2]
annulation
of
indoles,
ketones,
and
nitroolefins.
It
thus
conveniently
enabled
the
assembly
a
large
number
diversified
products
good
tolerance
broad
range
functional
groups.
Organic Letters,
Journal Year:
2017,
Volume and Issue:
19(6), P. 1370 - 1373
Published: March 1, 2017
A
novel
and
versatile
method
for
the
synthesis
of
2H-imidazoles
via
iron-catalyzed
[3
+
2]
annulation
from
readily
available
oxime
acetates
with
vinyl
azides
has
been
developed.
This
denitrogenative
process
involved
N–O/N–N
bond
cleavages
two
C–N
formations
to
furnish
2,4-substituted
2H-imidazoles.
protocol
was
performed
under
mild
reaction
conditions
needed
no
additives
or
ligands.
Furthermore,
this
is
a
green
involving
acetate
as
internal
oxidant,
acetic
acid,
nitrogen
byproducts.
ACS Catalysis,
Journal Year:
2019,
Volume and Issue:
9(5), P. 4179 - 4188
Published: March 28, 2019
A
4-HO-TEMPO-catalyzed
redox
strategy
for
the
synthesis
of
pyridines
through
annulation
cyclopropanols
and
oxime
acetates
has
been
developed.
This
protocol
features
good
functional
group
tolerance
high
chemoselectivity
also
promises
to
be
efficient
late-stage
functionalization
skeletons
drugs
natural
products.
Mechanism
studies
indicate
that
reaction
involves
in
situ
generated
α,β-unsaturated
ketones
imines
as
key
intermediates,
which
are
derived
from
via
a
TEMPO/TEMPOH
cycle,
respectively.
The
pyridine
products
formed
result
enones
with
followed
by
TEMPO-catalyzed
oxidative
aromatization
excess
acetates.
method
not
only
realizes
but
broadens
frontiers
TEMPO
catalysis.
The Journal of Organic Chemistry,
Journal Year:
2016,
Volume and Issue:
81(4), P. 1499 - 1505
Published: Jan. 20, 2016
Transition-metal-catalyzed
synthesis
of
N-heterocycles
from
oximes
has
been
previously
well
established.
In
this
paper,
for
the
first
time
a
metal-free
protocol
with
combinational
employment
iodine
and
triethylamine
demonstrated
to
be
effective
trigger
oxime-based
pyridines
high
chemo-selectivity
wide
functional
group
tolerance.
A
broad
range
were
prepared
in
moderate
excellent
yields.
While
neither
nor
could
transformation,
mechanistic
experiments
indicated
radical
pathway
reaction.
The
resultant
2-aryl-substituted
have
proved
versatile
building
blocks
transition-metal-catalyzed
C–H
functionalization
reactions.
