ChemistrySelect,
Journal Year:
2025,
Volume and Issue:
10(21)
Published: May 30, 2025
Abstract
Pyrans
are
a
class
of
six‐membered
heterocyclic
rings
containing
five
carbon
atoms
and
one
oxygen
atom.
They
non‐aromatic
in
nature,
bearing
two
double
bonds
the
ring.
The
bond
position
distinguishes
pyran
isomers,
namely,
2
H
‐pyran
4
‐pyran.
When
saturated
sp
3
is
located
next
to
an
atom,
it
known
as
‐pyran,
when
at
4‐position
with
respect
In
1962,
by
thermal
breakdown
2‐acetoxy‐3,4‐dihydro‐2
‐pyrans
were
produced
for
first
time,
their
characteristics
explored.
Numerous
synthetic
methods
have
been
disclosed
over
time
owing
broad
applications
diverse
fields,
mainly
drug
design,
pharmaceuticals,
material
science.
this
review,
we
highlight
recent
advancements
toward
substituted
4‐pyranone,
2‐pyranones,
focusing
on
reports
published
from
2019
till
date,
which
play
important
roles
both
organic
synthesis
types
functional
molecules.
The Journal of Organic Chemistry,
Journal Year:
2023,
Volume and Issue:
88(16), P. 11627 - 11636
Published: Aug. 9, 2023
Syntheses
of
highly
functionalized
4-alkylated
1,4-dihydropyridines
(1,4-DHPs)
from
cyclic
ethers
and
enaminones
via
iron(II)-mediated
oxidative
free
radical
cascade
C(sp3)-H
bond
functionalization/C(sp3)-O
cleavage/cyclization
reaction
have
been
first
developed.
This
novel
synthetic
strategy
offers
an
alternative
method
for
the
construction
1,4-DHPs
by
using
esters
as
C4
sources,
well
expands
application
in
heterocycle
synthesis.
Advanced Synthesis & Catalysis,
Journal Year:
2024,
Volume and Issue:
366(19), P. 4139 - 4144
Published: July 2, 2024
Abstract
A
copper‐catalyzed
annulation
of
enaminones
with
maleimides
was
developed
to
synthesize
various
pyrrolo[3,4‐e]isoindoles.
In
this
strategy,
2‐aminopyridine
served
as
a
traceless
directing
group,
and
target
products
were
obtained
in
54–72%
yields.
Moreover,
plausible
mechanism
for
reaction
proposed
based
on
several
control
experiments,
deuterium
exchange
previous
reports.
ChemistrySelect,
Journal Year:
2025,
Volume and Issue:
10(21)
Published: May 30, 2025
Abstract
Pyrans
are
a
class
of
six‐membered
heterocyclic
rings
containing
five
carbon
atoms
and
one
oxygen
atom.
They
non‐aromatic
in
nature,
bearing
two
double
bonds
the
ring.
The
bond
position
distinguishes
pyran
isomers,
namely,
2
H
‐pyran
4
‐pyran.
When
saturated
sp
3
is
located
next
to
an
atom,
it
known
as
‐pyran,
when
at
4‐position
with
respect
In
1962,
by
thermal
breakdown
2‐acetoxy‐3,4‐dihydro‐2
‐pyrans
were
produced
for
first
time,
their
characteristics
explored.
Numerous
synthetic
methods
have
been
disclosed
over
time
owing
broad
applications
diverse
fields,
mainly
drug
design,
pharmaceuticals,
material
science.
this
review,
we
highlight
recent
advancements
toward
substituted
4‐pyranone,
2‐pyranones,
focusing
on
reports
published
from
2019
till
date,
which
play
important
roles
both
organic
synthesis
types
functional
molecules.
