Convenient
access
to
6-alkylsulfonylmethyl
phenanthridines
has
been
demonstrated
both
under
thermal
and
visible-light
photoredox-catalyzed
conditions.
A
cascade
of
radical
cyclization
is
triggered
on
exposure
biphenyl
vinyl
azides
the
in-situ
generated
alkyl
sulfonyl
radicals
from
4-substituted
Hanztsch
esters
in
presence
an
SO2
surrogate.
Transition
metal-free,
mild
reaction
conditions,
broad
substrate
scope
constitute
some
highlights
approach.
Also,
synthetic
utility
accessed
demonstrated.
The
temperature-dependent
switching
behavior
of
the
saccharin
radical
is
demonstrated,
enabling
regiodivergent
C3–H
and
C7–H
functionalization
quinoxalin-2(1H)-ones.
was
generated
through
N–Br
bond
cleavage
in
N-bromosaccharin
(NBSA)
observed
to
transition
between
radicophile
roles.
At
−10
°C,
it
utilized
as
a
radicophile,
resulting
100%
C3-amination,
while
at
+35
acted
radical,
leading
exclusive
C7-bromination.
Radical
nucleophilicity
controlled
by
temperature
modulation.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(3), С. 1784 - 1796
Опубликована: Янв. 12, 2024
The
atom
transfer
radical
addition
(ATRA)
reaction
is
defined
as
a
method
for
introducing
halogenated
compounds
into
alkenes
via
mechanism.
In
this
study,
we
present
an
ATRA
approach
achieving
regioselective
functionalization
of
quinoxalin-2(1H)-ones
by
activating
C–Br
bonds
CBr4
and
subsequent
trihaloalkyl-carbofunctionalization
styrenes
employing
the
9-mesityl-10-methylacridinium
perchlorate
(Fukuzumi)
photocatalyst
under
3W
blue
LED
(450–470
nm)
irradiation.
This
three-component
cascade
process
demonstrates
remarkable
efficiency
in
synthesis
1-methyl-3-(3,3,3-tribromo-1-(4-chlorophenyl)propyl)quinoxalin-2(1H)-one
derivatives.
Chemistry - An Asian Journal,
Год журнала:
2024,
Номер
19(14)
Опубликована: Май 8, 2024
The
beginning
of
photochemical
reactions
revolutionized
synthetic
chemistry
through
sustainable
practices.
This
review
explores
cutting-edge
developments
in
leveraging
light-induced
processes
for
generating
cascaded
C-C
and
C-hetero
bonds
without
catalysts.
Significantly,
catalyst-free
photoinduced
methodologies
have
garnered
considerable
attention,
especially
the
creation
varied
heterocyclic
frameworks
drug
design
synthesis
natural
products.
article
delves
into
underlying
mechanisms,
addresses
limitations,
evaluates
various
methodologies,
emphasizing
potential
photocatalyst
transition
metal-free
to
enhance
sustainability.
Divided
two
sections,
it
covers
recent
strides
C-heteroatom
multiple
bond
formation
reactions.
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(13), С. 8133 - 8149
Опубликована: Июнь 15, 2023
In
recent
years,
catalysis
with
base
metal
manganese
has
received
a
significant
amount
of
interest.
Catalysis
complexes
having
N-heterocyclic
carbenes
(NHCs)
is
relatively
underdeveloped
in
comparison
to
the
extensively
investigated
catalysts
possessing
pincer
ligands
(particularly
phosphine-based
ligands).
Herein,
we
describe
synthesis
two
imidazolium
salts
decorated
picolyl
arms
(L1
and
L2)
as
NHC
precursors.
Facile
coordination
L1
L2
MnBr(CO)5
presence
resulted
formation
manganese(I)-NHC
(1
2)
an
air-stable
solid
good
isolated
yield.
Single-crystal
X-ray
analysis
revealed
structure
cationic
[Mn(CO)3(NHC)][PF6]
tridentate
N,C,N
binding
ligand
facile
fashion.
Along
few
known
manganese(I)
complexes,
these
Mn(I)-NHC
1
2
were
tested
for
hydrosilylation
terminal
alkynes.
Complex
was
proved
be
effective
catalyst
alkynes
selectivity
toward
less
thermodynamically
stable
β-(Z)-vinylsilanes.
This
method
provided
regioselectivity
(anti-Markovnikov
addition)
stereoselectivity
(β-(Z)-product).
Experimental
evidence
suggested
that
present
pathway
involved
organometallic
mechanism
manganese(I)-silyl
species
possible
reactive
intermediate.
Catalysis Science & Technology,
Год журнала:
2023,
Номер
14(1), С. 183 - 189
Опубликована: Ноя. 28, 2023
In
this
study,
we
demonstrate
the
proficiency
of
orthorhombic
CsPbBr
3
to
perform
C–H
chalcogenation
reactions
electron-rich
arenes
under
conditions
involving
polar
solvents,
aerobic
environments,
and
visible-light
irradiation.
Chemistry - An Asian Journal,
Год журнала:
2023,
Номер
18(21)
Опубликована: Сен. 25, 2023
The
increasing
global
warming
concerns
have
propelled
a
surge
in
the
demand
for
sustainable
energy
sources
within
domain
of
synthetic
organic
chemistry.
A
particularly
prominent
area
research
has
been
development
mild
strategies
generating
heterocyclic
compounds.
Heterocyclic
compounds
containing
boron
notably
risen
to
prominence
as
pivotal
reagents
myriad
transformations,
showcasing
their
wide-ranging
applicability.
This
comprehensive
review
is
aimed
at
collecting
literature
pertaining
borylation
reactions
induced
by
light,
specifically
focusing
on
photocatalyst-free
and
transition
metal-free
methodologies.
central
emphasis
delving
into
selective
mechanistic
investigations.
amalgamation
analysis
these
insights
elucidate
substantial
potential
inherent
eco-friendly
approaches
synthesizing
compounds,
thus
propelling
landscape
Asian Journal of Organic Chemistry,
Год журнала:
2024,
Номер
13(5)
Опубликована: Март 5, 2024
Abstract
Convenient
access
to
6‐alkylsulfonylmethyl
phenanthridines
has
been
demonstrated
both
under
non‐catalytic
thermal
and
visible‐light
photoredox‐catalyzed
conditions.
A
cascade
of
radical
cyclization
is
triggered
by
the
exposure
biphenyl
vinyl
azides
in‐situ
generated
alkyl
sulfonyl
radicals
from
4‐substituted
Hanztsch
esters
in
presence
an
SO
2
surrogate.
Transition
metal‐free,
mild
reaction
conditions,
broad
substrate
scope
constitute
some
highlights
approach.
Also,
synthetic
utility
accessed
demonstrated.
Synthesis,
Год журнала:
2023,
Номер
56(04), С. 585 - 596
Опубликована: Март 27, 2023
Abstract
A
useful
method
for
the
formation
of
benzimidazole-fused
phenanthridines
through
an
intramolecular
coupling
unactivated
C(sp2)–H
and
N(sp3)–H
bonds
using
N-iodosuccinimide
(NIS)
in
trifluoroethanol
(TFE)
is
presented.
The
synthesis
benzo[4,5]imidazo[1,2-f]phenanthridines
from
2-([1,1′-biphenyl]-2-yl)-1H-benzo[d]imidazole
derivatives
mild,
efficient,
sustainable,
with
high
yields
minimal
waste
generation.
control
experiments
EPR
studies
were
aimed
at
rationalizing
radical
pathway
reaction.
Specifically,
use
1,1-diphenylethylene,
TEMPO,
BHT,
DMPO
as
a
free-radical
spin-trapping
reagent
studies,
allowed
us
to
conceive
pathway.
gram-scale
further
supported
practical
utility
methodology
field
synthetic
chemistry.
