ACS Catalysis,
Год журнала:
2023,
Номер
13(7), С. 4894 - 4902
Опубликована: Март 27, 2023
C-4-selective
functionalization
of
azlactones
provides
access
to
α,α-disubstituted
unnatural
α-amino
acids,
which
has
been
extensively
investigated
in
the
past
decades.
However,
a
vast
majority
such
transformations
are
two-electron
transfer
reactions.
Herein,
leveraging
on
persistent
radical
effect,
we
develop
photocatalytic
energy
transfer-enabled
regioconvergent
alkylation
with
redox-active
esters
via
radical–radical
couplings.
This
strategy
is
extended
utilization
simple
alkanes
as
precursors,
whereby
aryl
play
dual
role
an
oxidant
and
hydrogen-atom-transfer
agent.
Notably,
excited
state
Ir(III)
photocatalyst
enables
selective
activation
unwanted
imine
products
through
triplet
transfer,
delivering
C-4-functionalized
high
regioselectivity.
Both
experimental
investigations
density
functional
theory
calculations
reaction
mechanism
were
performed,
supporting
EnT-enabled
coupling
pathways.
Chemical Society Reviews,
Год журнала:
2024,
Номер
53(3), С. 1068 - 1089
Опубликована: Янв. 1, 2024
Leveraging
light
energy
to
expose
the
‘dark’
reactive
states
describes
whole
essence
of
triplet–triplet
transfer.
This
offers
an
impressive
opportunity
conduct
a
multitude
diverse
reactions
and
access
sought-after
molecular
motifs.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(4), С. 2364 - 2374
Опубликована: Янв. 18, 2023
Sulfur(VI)
fluoride
exchange
(SuFEx)
gives
rise
to
a
plethora
of
high-valent
sulfur
linkages;
however,
the
availability
(aliphatic)
sulfonyl
manifolds
lag
behind,
owing
limited
sources
introducing
SO2F
moiety
via
classical
two-electron
approach.
Recently,
radical-based
methodologies
have
emerged
as
complementary
strategy
increase
diversity
accessible
click
partners.
In
this
work,
synthesis
bench-stable
sulfamoyl
reagent
is
presented,
which
may
undergo
sigma-bond
homolysis
upon
visible-light-induced
sensitization
form
protected
β-amino
fluorides
from
alkene
feedstocks.
Notably,
offers
an
appealing
access
various
building
blocks
for
peptido
fluorides,
relevant
in
medicinal
chemistry
context,
well
intriguing
entry
β-ammonium
sulfonates
and
β-sultams,
alkenes.
Densely
functionalized
1,3-sultones
were
obtained
by
employing
allyl
alcohols
substrates.
Surprisingly,
chloride-derived
β-imino
underwent
S-O
bond
formation
ring
closure
yield
rigid
cyclopropyl
sulfonate
ester
under
SuFEx
conditions.
Furthermore,
engaging
thiol-based
hydrogen
atom
donor
reaction,
reactivity
same
can
be
tuned
toward
direct
aliphatic
fluorides.
Mechanistic
experiments
indicate
energy
transfer
(EnT)-mediated
process.
The
transient
radical
adds
product
occurs
either
radical-radical
coupling
or
(HAT),
respectively.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(30), С. 16630 - 16641
Опубликована: Июль 24, 2023
β-(Hetero)arylethylamines
are
privileged
structural
motifs
found
in
many
high-value
organic
molecules,
including
pharmaceuticals
and
natural
products.
To
construct
these
important
molecular
skeletons,
previous
methods
mainly
achieved
by
amino(hetero)arylation
reaction
with
the
aid
of
transition
metals
preactivated
substrates.
Herein,
we
report
a
metal-free
photoinduced
intermolecular
for
single-step
installation
both
(hetero)aryl
iminyl
groups
across
alkenes
an
efficient
regioselective
manner.
This
method
shows
broad
scope
(up
to
124
examples)
excellent
tolerance
various
olefins─from
simplest
ethylene
complex
multisubstituted
can
all
participate
reaction.
Furthermore,
aminosulfonylation
be
also
conducted
presence
sodium
bisulfite
as
SO2
source.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(15), С. 10899 - 10907
Опубликована: Апрель 3, 2024
In
the
long-standing
quest
to
synthesize
fundamental
building
blocks
with
key
functional
group
motifs,
photochemistry
in
recent
past
has
comprehensively
established
its
attractiveness.
Amino
alcohols
are
not
only
functionally
diverse
but
ubiquitous
biologically
active
realm
of
compounds.
We
developed
bench-stable
bifunctional
reagents
that
could
then
access
sparsely
reported
γ-amino
directly
from
feedstock
alkenes
through
energy
transfer
(EnT)
photocatalysis.
A
designed
1,3-linkage
across
is
made
possible
by
intervention
a
radical
Brook
rearrangement
takes
place
downstream
EnT-mediated
homolysis
our
reagent(s).
combination
experimental
mechanistic
investigations
and
detailed
computational
studies
(DFT)
indicates
chain
propagated
reaction
pathway.
We
describe
an
efficient
acyl
esterification
method
for
alkenes
utilizing
acyloxime
esters
as
bifunctional
reagents
featuring
radical
acylation
and
congested
C–O
bond
formation.
This
approach
is
characterized
by
mild
photoredox
conditions,
high
step
atom
economy,
a
broad
substrate
scope,
excellent
regioselectivity.
A
variety
of
valuable
α-acyl
hindered
alcohol
esters,
including
those
obtained
via
gram-scale
synthesis
late-stage
functionalization
pharmaceutical
molecules,
were
presented,
demonstrating
its
synthetic
potential
practicability.
Journal of the American Chemical Society,
Год журнала:
2022,
Номер
144(47), С. 21664 - 21673
Опубликована: Ноя. 16, 2022
Radical
addition
reactions
of
olefins
have
emerged
as
an
attractive
tool
for
the
rapid
assembly
complex
structures,
and
plentiful
applications
in
organic
synthesis,
however,
such
are
often
limited
to
polymerization
or
1,2-difunctionalization.
Herein,
we
disclose
unprecedented
radical
relay
1,4-oxyimination
two
electronically
differentiated
with
a
class
bifunctional
oxime
carbonate
reagents
via
energy
transfer
strategy.
The
protocol
is
highly
chemo-
regioselective,
three
different
chemical
bonds
(C-O,
C-C,
C-N
bonds)
were
formed
single
operation
orchestrated
manner.
Notably,
this
reaction
provides
access
large
variety
structurally
diverse
products,
obtained
products
could
be
easily
converted
into
valuable
biologically
relevant
δ-hydroxyl-α-amino
acids.
With
combination
experimental
theoretical
methods,
mechanism
has
been
investigated.
Theoretical
calculations
reveal
that
chain
might
operate
reaction.
ACS Catalysis,
Год журнала:
2023,
Номер
13(14), С. 9542 - 9549
Опубликована: Июль 5, 2023
Highly
strained
1,3-disubstituted
bicyclo[1.1.1]pentanes
(BCPs)
have
been
established
as
bioisosteres
of
para-disubstituted
benzene
because
they
impart
valuable
pharmacokinetic
properties.
Herein,
we
demonstrate
an
energy
transfer-mediated
protocol
for
acylboration
[1.1.1]propellanes
that
allows
the
direct
construction
various
carbonyl
species,
such
carbamoyl-,
carboxyl-,
and
acyl-,
in
tandem
with
synthetically
versatile
pinacol
boronate
(Bpin)
groups
onto
BCP
substructure
under
simple
reaction
conditions.
Moreover,
drug-like
molecules
containing
boronates
are
further
submitted
to
late-stage
functionalization
events.
Several
important
transformations
Bpin
functional
group
boronates,
including
photoinduced
cross-coupling
reactions
BCP-BF3K,
derived
from
BCP-Bpin,
were
successfully
performed
showcase
synthetic
utility.
Additionally,
diverse
elaborate
mechanistic
investigations
provide
insights,
a
plausible
mechanism
is
proposed.
Chemical Science,
Год журнала:
2023,
Номер
14(9), С. 2447 - 2454
Опубликована: Янв. 1, 2023
Intermolecular
carboamination
of
olefins
offers
a
powerful
platform
for
the
rapid
construction
structurally
complex
amines
from
abundant
feedstocks.
However,
these
reactions
often
require
transition-metal
catalysis,
and
are
mainly
limited
to
1,2-carboamination.
Herein,
we
report
novel
radical
relay
1,4-carboimination
across
two
distinct
with
alkyl
carboxylic
acid-derived
bifunctional
oxime
esters
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(16)
Опубликована: Фев. 27, 2023
Although
the
direct
conversion
of
gaseous
acetylene
into
value-added
liquid
commodity
chemicals
is
becoming
increasingly
attractive,
majority
established
methodologies
are
focused
on
cross-coupling,
hydro-functionalization,
and
polymerization.
Herein,
we
describe
a
1,2-difunctionalization
method
that
inserts
directly
readily
available
bifunctional
reagents.
This
provides
access
to
diverse
C2-linked
1,2-bis-heteroatom
products
in
high
regio-
stereoselectivity
along
with
opening
up
previously
unexplored
synthetic
directions.
In
addition,
demonstrate
this
method's
potential
by
converting
obtained
functionalized
molecules
chiral
sulfoxide-containing
bidentate
ligands.
Using
combination
experimental
theoretical
methods,
mechanism
for
insertion
reaction
was
investigated.
Organic Letters,
Год журнала:
2023,
Номер
25(10), С. 1782 - 1786
Опубликована: Март 8, 2023
A
metal-free
photosensitized
three-component
reaction
of
oxime
esters,
alkenes,
and
DABCO·(SO2)2
was
developed.
This
protocol
could
accommodate
a
wide
substrate
scope,
including
activated
unactivated
alkenes
aryl
aliphatic
carboxylic
acid
delivering
broad
range
β-amino
sulfones
in
moderate
to
high
yields.
The
insertion
SO2
as
linker
moiety
allows
the
manipulation
functionality
process,
expanding
utility
esters
bifunctional
reagents.