Photodriven Radical-Polar Crossover Cyclization Strategy: Synthesis of Pyrazolo[1,5-a]pyridines from Diazo Compounds
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(12), P. 2511 - 2516
Published: March 20, 2024
This
work
demonstrates
the
synthesis
of
a
variety
perfluoroalkyl
heterocycles
via
visible-light-driven
radical-polar
crossover
cyclization
strategy.
In
this
process,
single-electron
reduction/SNV-type/cyclization
sequences
follow
radical
addition
reaction
diazoester,
which
differs
from
current
role
diazoesters
as
precursors/acceptors.
transformation
excellent
functional
group
compatibility
and
allows
for
modification
many
bioactive
molecules
with
diazoesters.
Such
could
represent
novel
approach
to
photochemical
diazo
compounds.
Language: Английский
Zinc‐Catalysed [3+2] Cycloaddition of Enaminone with Tosylhydrazide to Synthesise 1H‐pyrazole via C–N and S–N Bond Cleavage
Asian Journal of Organic Chemistry,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Nov. 14, 2024
Abstract
A
novel
and
practical
zinc‐catalysed
synthesis
of
1
H
‐pyrazole
has
been
developed.
The
one‐pot
protocol
enables
the
cycloaddition
enaminone
tosylhydrazide
via
C−N
S−N
bond
breaking
process,
leading
to
diverse
mono‐substituted
pyrazole
derivatives
in
high
yields.
Moreover,
easily
accessible
materials,
broad
substrate
scope
with
excellent
functional
group
tolerance,
ease
isolation
open‐air
conditions
are
key
features
present
method.
Language: Английский