ACS Catalysis,
Journal Year:
2023,
Volume and Issue:
13(24), P. 16105 - 16113
Published: Dec. 5, 2023
Despite
remarkable
progress
in
photocatalytic
hydrogen
atom
transfer
(HAT)-induced
C(sp3)–H
functionalization,
achieving
to
C(sp3)–P
transformation
by
the
HAT
process
remains
highly
challenging
due
P-reagents'
compatibility
issues.
α-Aminophosphonic
acids
have
shown
great
potential
medicinal
chemistry,
yet
their
synthesis
is
hindered
limited
substrate
scopes,
poor
functional
group
tolerance,
and
reliance
on
prefunctionalized
substrates,
restricting
broad
applications.
Herein,
we
report
HAT-induced
α-C(sp3)–H
phosphonylation
of
aliphatic
amines,
providing
rapid
access
structurally
diverse
α-aminophosphonates
from
abundant
amines.
Leveraging
intramolecular
HAT,
radical
polar
crossover,
an
Arbuzov-type
cascade,
challenges
associated
with
were
overcome.
This
protocol
features
base-free,
redox-neutral,
mild
conditions
employing
amines
as
limiting
reagents,
allows
for
late-stage
complex
drug
molecules
possessing
amine
moieties.
The Journal of Organic Chemistry,
Journal Year:
2023,
Volume and Issue:
88(11), P. 7401 - 7424
Published: May 12, 2023
Herein,
we
report
a
blue-light-driven
amination
of
C(sp2)-H
bond
naphthoquinones
and
quinones
with
the
N-H
primary
secondary
amines
for
synthesis
2-amino-naphthoquinones
2-amino-quinones.
The
coupling
wide
array
aliphatic,
aromatic,
chiral,
primary,
having
electron
donating
(-CH3,
-OCH3,
-SCH3),
withdrawing
(-F,
-Cl,
-Br,
-I),
CO2H,
-OH,
-NH2
groups
acidic
protons
selectively
occurred
to
afford
C-N
coupled
in
60-99%
yields
hydrogen
gas
as
byproduct
methanol
solvent
without
using
any
additional
reagents,
additives,
oxidant
under
blue
light
irradiation.
Mechanistic
insight
by
DFT
computation,
controlled
experiments,
kinetic
isotopic
effect,
substitution
effect
substrates
suggest
that
reaction
proceeds
radical
pathway
which
naphthoquinone
forms
highly
oxidizing
naphthoquinonyl
biradical
upon
irradiation
(457
nm).
Consequently,
transfer
from
electron-rich
amine
an
leads
anion
aminyl
cation,
followed
proton
delocalization
leading
carbon-centered
radical.
cross-coupling
nitrogen
radicals
bond,
subsequent
elimination
(which
was
also
confirmed
GC-TCD),
affording
2-amino-1,4-naphthoquinone
metal-,
reagent-,
base-,
oxidant-free
conditions.
Dalton Transactions,
Journal Year:
2024,
Volume and Issue:
53(17), P. 7498 - 7516
Published: Jan. 1, 2024
Incorporating
phosphonate
groups
onto
the
phenyl
substituents
of
meso
-tetraphenylporphyrins
proves
advantageous
for
their
utilization
in
photocatalysis.
Coordination Chemistry Reviews,
Journal Year:
2024,
Volume and Issue:
510, P. 215819 - 215819
Published: April 10, 2024
The
applicability
of
ruthenium
tris(bipyridine)
complexes
in
fields
like
photoactivated
chemotherapy
or
photocatalysis
requires
in-depth
understanding
their
excited
state
deactivation
mechanism.
In
particular,
the
quenching
luminescence
from
lowest
triplet
metal-to-ligand
charge-transfer
()
ligand
photorelease
relies
on
fine-tuning
energetics
higher-lying
metal-centered
states
().
this
contribution,
we
critically
review
different
kinetic
models
commonly
used
to
interpret
thermal
activation
minimum.
Further,
extend
our
recently
introduced
model
(Angew.
Chem.
Int.
Ed.
2023,
62,
e202308803)
for
(bpy
=
2,2'-bipyridine)
a
set
homoleptic
tris(bipyridine)ruthenium
(II)
derivatives.
This
has
been
selected
cover
wide
range
electron
-withdrawing/-donating
substituents
periphery
bipyridyl
ligands
(4,4'--2,2'-bpy;
R=
,
and
),
basis
Hammett's
constant
R
functional
group.
Our
calculations
show
that
with
donating
groups
decay
predominantly
via
one
Jahn-Teller
isomer
(the
so-called
-trans
conformation),
while
those
withdrawing
tend
through
-cis
isomer).
We
discuss
structure/property
relationships
focus
how
steer
states.
work
opens
pathway
rationally
use
substitution
enhance
quench
lifetimes
also
provides
guidelines
understand
better
non-radiative
mechanisms
metal
complexes.
Green Chemistry,
Journal Year:
2023,
Volume and Issue:
25(11), P. 4528 - 4535
Published: Jan. 1, 2023
A
photocatalytic
phosphorylation
of
heteroatom
nucleophiles
has
been
achieved
via
the
direct
coupling
phosphorus-centered
radical
cations
with
nucleophiles.
The Journal of Organic Chemistry,
Journal Year:
2023,
Volume and Issue:
88(4), P. 2612 - 2620
Published: Feb. 1, 2023
An
external
photocatalyst-free
benzylic
C-H
functionalization
with
fluorenones
under
visible-light
irradiation
has
been
achieved.
This
transformation
provides
an
efficient
synthetic
approach
to
9-benzylated
fluorenols
in
≤91%
yield
100%
atom
economy
mild
conditions.
Spectroscopic
studies
suggest
that
a
reductive
quenching
of
photoexcited
toluene
derivatives
generates
ketyl
radicals
and
benzyl
radicals,
which
undergo
cross-coupling
afford
the
desired
fluorenols.
Dalton Transactions,
Journal Year:
2023,
Volume and Issue:
53(2), P. 535 - 551
Published: Nov. 21, 2023
Ru(
ii
)
complexes
with
phosphonate-substituted
phenanthroline
ligands
exhibited
higher
efficiency
than
the
benchmark
photocatalyst
[Ru(bpy)
3
]
2+
in
photoredox-catalyzed
reactions
and
could
be
recycled
through
water
extraction
for
reuse.
ChemPhotoChem,
Journal Year:
2024,
Volume and Issue:
8(12)
Published: Aug. 21, 2024
Abstract
The
one‐pot
synthesis
of
a
total
32
ruthenium(II)
and
osmium(II)
photosensitizers
bearing
substituted
2,2’‐bipyridines,
1,10‐phenanthrolines,
diaza
ligands
is
reported.
Whereas
most
these
were
already
reported
in
the
literature,
present
study
offers
extensive
datasets
ground‐
excited‐state
properties
highly
desirable
for
future
development
e.
g.,
machine
learning,
artificial
intelligence,
photoredox
catalysis.
All
absorbed
light
intensely
visible
part
spectrum,
with
Os(II)
absorbing
further
into
red
part.
Excited‐state
lifetimes
photoluminescence
quantum
yields
generally
larger
Ru(II)
than
analogs,
which
agrees
energy
gap
law.
redox
potentials
determined
all
investigated
covering
range
−0.21
to
−1.35
V
vs
.
SCE
oxidation
0.14
1.48
reduction.
A
procedure
counterion
exchange
generate
corresponding
PF
6
−
,
Cl
BF
4
NO
3
OTf
ClO
BAr
F−
six
photosensitizers.
synthetic
ease,
detailed
report
fundamental
photophysical
properties,
broad
open
opportunities
systematic
investigations
several
applications
streamline
developments
