Synlett,
Год журнала:
2024,
Номер
35(17), С. 1937 - 1946
Опубликована: Май 14, 2024
Abstract
The
cleavage
of
double
bonds
in
alkenes
constitutes
an
integral
process
converting
feedstock
materials
into
high-value
synthetic
intermediates.
Well-known
examples
such
as
the
oxidative
olefins
and
olefin
metathesis
only
facilitate
synthesis
oxygen-containing
compounds
recombination
olefins.
Therefore,
it
is
appealing
to
extend
C=C
bond
yield
more
abundant
transformations.
Herein,
we
report
a
novel
photocatalytic
approach
for
deconstructive
carboxylation
with
CO2
carboxylic
acids
absence
transition
metals.
Compared
reported
carboxylations
during
which
carbon
numbers
are
typically
increased,
achieve
exchange
dioxide
one
carbons
alkene
bond,
thus
providing
unchanged
when
terminal
used.
Chemical Science,
Год журнала:
2024,
Номер
15(31), С. 12442 - 12450
Опубликована: Янв. 1, 2024
A
practical
and
general
C-4
functionalization
strategy
of
unbiased
pyridines
is
developed
by
identifying
a
readily
synthesized
substituted
urea
as
the
pyridine
activation
reagent.
Organic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(19), С. 5545 - 5552
Опубликована: Янв. 1, 2024
Site-selective
silylations
of
electron-deficient
pyridines
is
presented,
the
C4-to-C5
selectivity
can
be
controlled
by
adjusting
bulkiness
chlorosilanes.
Chemistry - A European Journal,
Год журнала:
2024,
Номер
31(2)
Опубликована: Ноя. 28, 2024
The
pyridine
core
is
a
crucial
component
in
numerous
FDA-approved
drugs
and
Environmental
Protection
Agency
(EPA)
regulated
agrochemicals.
It
also
plays
significant
role
ligands
for
transition
metals,
alkaloids,
catalysts,
various
organic
materials
with
diverse
properties,
making
it
one
of
the
most
important
structural
frameworks.
However,
despite
its
significance,
direct
selective
functionalization
still
relatively
underdeveloped
due
to
electron-deficient
nature
strong
coordinating
ability
nitrogen.
Among
variety
synthetic
transformation,
C-H
bond
straightforward
atom
economical
approach
it's
advantageous
late-stage
containing
drugs.
In
recent
years,
innovative
strategies
regioselective
pyridines
azines
have
emerged,
offering
benefits
such
as
high
regioselectivity,
mild
conditions,
enabling
transformations
that
were
challenging
traditional
methods.
This
review
emphasizes
latest
advancements
meta
para-C-H
through
approaches,
including
phosphonium
salts,
photocatalytic
methods,
temporary
de-aromatization,
Minisci-type
reactions,
metal-catalyzed
activation
techniques.
We
discuss
advantages
limitations
these
current
methods
aim
inspire
further
progress
this
field.
A
visible-light
photocatalytic
nucleophilic
addition
of
4-pyridylphosphonium
salts
to
CO2
and
carbonyl
compounds
is
reported.
The
reaction
has
mild
conditions,
good
functional
group
tolerance,
a
wide
range
substrates.
Mechanistic
studies
show
that
the
may
occur
through
pyridylphosphonium
salt
radical
anion,
pyridyl
radical,
anion
intermediates.
By
combination
with
C4-H
phosphination,
this
method
can
be
applied
late-stage
C-H
functionalization
drugs
containing
pyridine
unit.
We
report
herein
the
palladium-catalyzed
Hiyama
cross-coupling
of
heterocyclic
phosphonium
salts
with
diverse
(hetero)arylsilanes
through
C-P
bond
cleavage,
providing
an
alternative
approach
for
highly
regioselective
functionalization
pyridines
and
relevant
nitrogen-containing
heterocycles.
This
silicon-based
protocol
is
amenable
to
gram-scale
synthesis
also
applicable
late-stage
pharmaceutically
complex
molecules.
The Journal of Organic Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Июнь 5, 2025
Although
significant
progress
has
been
made
in
achieving
site-selective
C-O
bond
functionalization
specific
substrates,
the
selective
cleavage
and
of
C(sp3)-O
bonds
ethers
remain
a
fundamental
challenge
synthetic
chemistry.
Herein,
we
present
an
efficient
carboxylation
method
via
photoredox-catalyzed
benzylic
with
carbon
dioxide
(CO2).
Diverse
primary,
secondary,
tertiary
benzyl
undergo
CO2
to
generate
valuable
aryl
acetic
acids,
including
several
drug
molecules.
This
photocatalyzed
reaction
is
operationally
simple
implement
versatile
for
various
ethers,
exhibiting
favorable
compatibility
diverse
functional
groups.
Mechanistic
studies
indicate
that
single
electron
transfer
(SET)
reduction
might
be
key
generating
highly
reactive
radical
anion
intermediate,
which
could
another
SET
process
carbanions
CO2.
