Organic Letters,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 11, 2025
An
EnT-mediated
C3-N-heteroarylation
of
2-aryl
quinoxalines
via
decarboxylative
radical-radical
cross-coupling
(C(sp2)-C(sp2))
with
oxime
esters
is
presented.
Upon
photoactivation,
the
triplet
energy
photocatalyst
transferred
to
both
reacting
partners
(oxime
ester
and
2-phenylquinoxaline).
The
excited
undergoes
fragmentation
a
C-centered
N-heteroaryl
radical
an
N-centered
imine
radical.
former
attacks
C3
site
quinoxaline
diradical,
while
latter
acts
as
hydrogen
atom
abstractor
(HAA).
Computational
studies
revealed
that
C-C
bond
formation
heteroaryl
energetically
more
favorable
than
C-N
formation.
Chemical Reviews,
Journal Year:
2022,
Volume and Issue:
122(24), P. 17479 - 17646
Published: Oct. 14, 2022
Alkenes
and
their
derivatives
are
featured
widely
in
a
variety
of
natural
products,
pharmaceuticals,
advanced
materials.
Significant
efforts
have
been
made
toward
the
development
new
practical
methods
to
access
this
important
class
compounds
by
selectively
activating
alkenyl
C(sp2)–H
bonds
recent
years.
In
comprehensive
review,
we
describe
state-of-the-art
strategies
for
direct
functionalization
sp2
C–H
C–F
until
June
2022.
Moreover,
metal-free,
photoredox,
electrochemical
also
covered.
For
clarity,
review
has
divided
into
two
parts;
first
part
focuses
on
currently
available
using
different
alkene
as
starting
materials,
second
describes
bond
easily
accessible
gem-difluoroalkenes
material.
This
includes
scope,
limitations,
mechanistic
studies,
stereoselective
control
(using
directing
groups
well
metal-migration
strategies),
applications
complex
molecule
synthesis
where
appropriate.
Overall,
aims
document
considerable
advancements,
current
status,
emerging
work
critically
summarizing
contributions
researchers
working
fascinating
area
is
expected
stimulate
novel,
innovative,
broadly
applicable
functionalizations
coming
Green Chemistry,
Journal Year:
2023,
Volume and Issue:
25(16), P. 6120 - 6148
Published: Jan. 1, 2023
This
article
presents
a
review
of
the
reports
on
catalyst-free
mechanochemical
organic
transformations
and
ability
to
initiate
reactions
that
are
extremely
difficult/impossible
occur
is
notable
advancement
process.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(32)
Published: June 20, 2023
Recent
years
have
witnessed
marked
progress
in
the
efficient
synthesis
of
various
enantioenriched
1,2,3,4-tetrahydroquinoxalines.
However,
enantio-
and
diastereoselective
access
to
trans-2,3-disubstituted
1,2,3,4-tetrahydroquinoxalines
remains
much
less
explored.
Herein
we
report
that
a
frustrated
Lewis
pair-based
catalyst
generated
via
situ
hydroboration
2-vinylnaphthalene
with
HB(C6
F5
)2
allows
for
one-pot
tandem
cyclization/hydrosilylation
1,2-diaminobenzenes
1,2-diketones
commercially
available
PhSiH3
exclusively
afford
high
yields
excellent
diastereoselectivities
(>20
:
1
dr).
Furthermore,
this
reaction
can
be
rendered
asymmetric
by
using
an
borane-based
derived
from
binaphthyl-based
chiral
diene
give
rise
almost
complete
diastereo-
enantiocontrol
dr,
up
>99
%
ee).
A
wide
substrate
scope,
good
tolerance
diverse
functionality
20-gram
scale
production
are
demonstrated.
The
diastereocontrol
achieved
judicious
choice
borane
hydrosilane.
catalytic
pathway
origin
stereoselectivity
elucidated
mechanistic
experiments
DFT
calculations.
Green Chemistry,
Journal Year:
2022,
Volume and Issue:
24(16), P. 6215 - 6223
Published: Jan. 1, 2022
WEPA,
a
waste
biomass-derived
catalyst,
was
used
to
synthesize
quinoxalines
from
aryl/heteroaryl
1,2-diamines
and
α-hydroxy
ketones
via
metal
catalyst/added
oxidant-free
sequential
condensation–cyclization–oxidation
process.
Organic Letters,
Journal Year:
2023,
Volume and Issue:
25(20), P. 3806 - 3811
Published: May 17, 2023
A
Mn(I)-catalyzed
site-selective
nondirected
C3-maleimidation
of
quinoxaline
is
established.
Herein,
the
electrophilic
C3-metalation
precedes
over
o-directed
strategy
to
access
diversely
substituted
quinoxaline-appended
succinimides.
The
products
undergo
PIFA-promoted
C(sp2)-C(sp3)
spirocyclization
via
π-electrons
drifting
from
aryls
and
Selectfluor-mediated
dehydrogenation
succinimide
at
room
temperature.
Organic & Biomolecular Chemistry,
Journal Year:
2023,
Volume and Issue:
21(7), P. 1518 - 1530
Published: Jan. 1, 2023
A
highly
efficient
pot,
atom,
and
step
economical
method
for
the
construction
of
pharmacologically
potent
structurally
functionalized
1,4-dihydropyridines,
quaternary
centered
C-3
spiro[indoline-3,4'-pyridines],
C-11
spiro[indeno[1,2-b]quinoxaline-11,4'-pyridines]
via
rose
bengal
photoredox
catalysis
under
blue
LED
irradiation
in
an
aqueous
medium
at
room
temperature
has
been
developed.
The
products
were
isolated
excellent
yields
within
a
short
reaction
time
variety
functional
groups
transition
metal-
ligand-free
energy-efficient
conditions
green
solvent
system
with
high
mass
efficiency
process
intensity,
which
are
key
advantages
current
work.
