Angewandte Chemie,
Год журнала:
2024,
Номер
136(38)
Опубликована: Июнь 21, 2024
Abstract
In
this
study,
we
introduce
a
novel
intramolecular
hydrogen
atom
transfer
(HAT)
reaction
that
efficiently
yields
azetidine,
oxetane,
and
indoline
derivatives
through
mechanism
resembling
the
carbon
analogue
of
Norrish‐Yang
reaction.
This
process
is
facilitated
by
excited
triplet‐state
carbon‐centered
biradicals,
enabling
1,5‐HAT
suppressing
critical
1,4‐biradical
intermediates
from
undergoing
Norrish
Type
II
cleavage
reaction,
pioneering
unprecedented
1,6‐HAT
reactions
initiated
alkenes.
We
demonstrate
synthetic
utility
compatibility
method
across
various
functional
groups,
validated
scope
evaluation,
large‐scale
synthesis,
derivatization.
Our
findings
are
supported
control
experiments,
deuterium
labeling,
kinetic
studies,
cyclic
voltammetry,
Stern–Volmer
density
theory
(DFT)
calculations.
ACS Catalysis,
Год журнала:
2023,
Номер
13(14), С. 9806 - 9816
Опубликована: Июль 11, 2023
Cyclopropanes
bearing
contiguous
all-carbon
quaternary
centers
continue
to
attract
attention
due
their
bioactivities.
However,
methods
obtain
cyclopropanes
with
remain
largely
unexplored
the
high
steric
hindrance
of
these
compounds.
Herein,
we
report
a
visible-light-mediated
energy-transfer
(EnT)
strategy
realize
in
situ
donor/donor
carbenes
from
readily
available
N-tosylhydrazones,
facilitating
synthesis
highly
congested
EWG-free
cyclopropanes.
Through
this
approach,
are
rapidly
installed
into
complex
bioactive
molecules,
fluorescent
and
other
useful
building
blocks
that
challenging
synthesize.
Detailed
mechanistic
reactions
DFT
studies
clearly
demonstrated
role
photosensitizer,
formation
carbenes,
necessity
light
base
system.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(48)
Опубликована: Окт. 7, 2022
Abstract
The
synthesis
of
2‐azetidinones
(β‐lactams)
from
simple
acrylamide
starting
materials
by
visible‐light‐mediated
energy
transfer
catalysis
is
reported.
reaction
features
a
C(sp
3
)−H
functionalization
via
variation
the
Norrish–Yang
photocyclization
involving
carbon‐to‐carbon
1,5‐hydrogen
atom
(supported
deuterium
labelling
and
DFT
calculations)
can
be
used
for
construction
diverse
range
β‐lactam
products.
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(16), С. 3296 - 3306
Опубликована: Янв. 1, 2023
This
review
covers
recent
advances
towards
the
stereoselective
synthesis
of
β-lactam
derivatives,
which
is
a
research
topic
great
interest
due
to
biological
activity
these
molecules.
Advanced Synthesis & Catalysis,
Год журнала:
2024,
Номер
366(15), С. 3310 - 3315
Опубликована: Июнь 13, 2024
Abstract
Sulfonyl
chlorides
are
a
synthetically
attractive
source
of
sulfonyl
radicals
in
photoredox
catalysis
and
useful
precursors
the
synthesis
sulfones.
Sulfamoyl
chlorides,
on
other
hand,
remain
poorly
represented
despite
their
similar
potential.
In
this
study,
N
‐chlorosulfonylated
β‐lactams
were
prepared
from
readily
available
utilized
an
atom
transfer
radical
addition
(ATRA)
reaction
with
variety
olefins,
producing
β‐lactam
sulfonamides
49–95%
yields.
β‐Lactams
fused
to
dihydro‐1,2‐thiazine
ring
which
closely
resemble
carbacephems,
widely
used
class
antibiotics,
also
synthesized
by
intra‐molecular
ATRA
reaction.
This
methodology
enables
preparation
sulfonamides,
compounds
that
great
interest
pharmacology.
Organic Letters,
Год журнала:
2024,
Номер
26(26), С. 5500 - 5505
Опубликована: Июнь 20, 2024
Herein,
we
present
a
photoinduced
diastereoselective
C-3
functionalization
of
electrophilic
β-glycosyl
β-lactams.
The
developed
protocol
is
simple,
mild,
and
scalable
explores
the
use
3-exomethylene
β-lactams
as
reaction
partners
in
Giese
type
reaction.
key
nucleophilic
alkyl
radical
generated
by
electron
transfer
process
EDA
complex
formed
NHPI
Hantzsch
esters.
hydrogen
atom
to
β-lactam
intermediate
enables
synthesis
various
N-phenyl
Organic Chemistry Frontiers,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
Successive
energy-transfer-mediated
dearomative
[2π
+
2σ]
cycloaddition/1,6-HAT
cascade
reaction
of
quinolines
with
bicyclo[1.1.0]butanes
provides
a
facile
synthesis
pyridine-fused
3D
complicated
molecules.
A
thioxanthone‐catalyzed
2,2,2‐trifluoroethoxyamination
of
olefins
is
developed
via
the
formation
corresponding
alkoxy
and
iminyl
radicals
using
unprecedented,
easily
prepared,
bench‐stable
oxime
ethers
as
bifunctional
reagents.
To
bypass
possible
side
reactions
(1,2‐Hydrogen
Atom
Transfer
(HAT),
H‐abstraction,
β‐scission),
high
reactivity
radical
fine‐tuned
to
promote
selective
challenging
a
COCH
2
CF
3
bond.
This
reaction,
involving
triplet
energy
transfer
process,
allows
concomitant
CN
COAlk
bond,
so
far
uncharted,
ether
Hence,
difunctionalization
myriad
electron‐rich
alkenes
selectively
afforded
anti‐Markovnikov
products
with
large
functional
group
tolerance
(44
examples,
up
77%
yield),
offering
straightforward
complementary
regioselectivity
compared
existing
approaches
for
2,2,2‐trifluoroethanol.
Post‐functionalization
mechanistic
investigations
provided
key
insights
into
reaction
mechanism
this
transformation.
