ACS Catalysis,
Год журнала:
2022,
Номер
12(24), С. 15750 - 15757
Опубликована: Дек. 7, 2022
A
photochemical
synthesis
of
brominated
α,α-difluoro-γ-lactones
from
cinnamyl
alcohols
and
ethyl
bromodifluoroacetate
is
reported
via
one-pot
Giese
addition/lactonization/halogen-atom
transfer
(XAT)
processes.
This
transformation
provides
in
moderate
to
good
diastereoselectivities.
The
reaction
affords
a
rapid
increase
molecular
complexity
organofluorine
chemical
space.
Dispersion-corrected
density
functional
theory
(DFT)
calculations
experiments
support
lactonization-induced
radical
chain
mechanism
which
long-lived
intermediate
undergoes
diastereoselective
halogen-atom
restart
the
cycle.
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(9), С. 6252 - 6262
Опубликована: Апрель 12, 2023
A
method
for
performing
radical
difunctionalization
of
alkenes
using
fluorinated
halides
and
a
nucleophilic
component
(thiolate
iodide
anions)
is
described.
These
fragments
serve
as
redox
active
groups
subsequent
transformations.
The
reaction
involves
photoredox
generation
radicals,
their
addition
to
the
double
bond
followed
by
copper-promoted
C-S
or
C-I
formation.
primary
products
can
be
further
coupled
with
silyl
enol
ethers,
α-(trifluoromethyl)styrenes,
trimethylsilyl
cyanide
affording
variety
compounds.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(31), С. 21271 - 21279
Опубликована: Июль 23, 2024
1,2-Difunctionalization
of
styrenes,
adding
two
distinct
functional
groups
across
the
C═C
double
bond,
has
emerged
as
a
powerful
tool
for
enhancing
molecular
complexity.
Herein,
we
report
development
regioconvergent
β-acyloxylation-α-ketonylation
styrenes
through
bromo/acyloxy
transposition
(BrAcT)
and
excited-state
copper
catalysis.
This
approach
is
amenable
to
gram-scale
synthesis
tolerates
wide
range
complex
frameworks,
including
derivatives
natural
products
marketed
drugs.
Our
experimental
computational
studies
suggest
unique
mechanism
featuring
dynamic,
ionic
BrAcT
process
copper-catalyzed
redox
reactions.
We
anticipate
that
this
could
serve
broadly
applicable
versatile
strategy
β-acyloxylation-α-functionalization
creating
valuable
intermediates
preparing
new
pharmaceuticals,
agrochemicals,
materials.
ACS Central Science,
Год журнала:
2024,
Номер
10(11), С. 2016 - 2027
Опубликована: Авг. 16, 2024
Methyl
groups
are
ubiquitous
in
natural
products
and
biologically
active
compounds,
but
methods
for
their
selective
transformation
such
structures
limited.
For
example,
terpenoids
contain
many
methyl
groups,
due
to
biosynthetic
pathways,
few
reactions
of
these
have
been
reported.
We
demonstrate
that
the
combination
C–H
silylation
oxidation
proximal
native
hydroxyl
or
carbonyl
occurs
a
range
show
installed
group
serves
as
toehold
enable
substitution,
elimination,
integration
carbon
into
terpenoid
skeleton
by
cleavage
C–C
bonds.
In
one
case,
substitution
entire
further
decarboxylative
coupling.
second,
with
hydrogen
photochemical
hydrodecarboxylation
epimerization
retro-Claisen
condensation.
third,
photocatalytic
decarboxyolefination
formally
eliminates
methane
from
starting
structure
generate
terminal
olefin
transformations.
Finally,
Dowd–Beckwith-type
rearrangement
cleaves
nearby
bond
integrates
ring,
forming
derivatives
unusual
difficult-to-access
expanded
rings.
This
strategy
transform
synthon
marks
distinct
approach
restructuring
skeletons
complex
architectures
adding
functional
relevant
medicinal
chemistry.
Chemical Science,
Год журнала:
2024,
Номер
unknown
Опубликована: Янв. 1, 2024
A
properly
designed
chiral
copper
complex
with
a
hybrid
tridentate
ligand
enables
photocatalytic
asymmetric
cyanoalkylalkynylation
of
olefins
using
cycloketone
oxime
esters
as
the
precursors.
ACS Catalysis,
Год журнала:
2022,
Номер
12(24), С. 15750 - 15757
Опубликована: Дек. 7, 2022
A
photochemical
synthesis
of
brominated
α,α-difluoro-γ-lactones
from
cinnamyl
alcohols
and
ethyl
bromodifluoroacetate
is
reported
via
one-pot
Giese
addition/lactonization/halogen-atom
transfer
(XAT)
processes.
This
transformation
provides
in
moderate
to
good
diastereoselectivities.
The
reaction
affords
a
rapid
increase
molecular
complexity
organofluorine
chemical
space.
Dispersion-corrected
density
functional
theory
(DFT)
calculations
experiments
support
lactonization-induced
radical
chain
mechanism
which
long-lived
intermediate
undergoes
diastereoselective
halogen-atom
restart
the
cycle.
