Authorea (Authorea),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Jan. 30, 2024
The
development
of
efficient
and
sustainable
methods
to
obtain
spirocyclic
compounds
is
significance
as
these
structures
are
widely
found
in
pharmaceuticals
agrochemicals.
Herein,
we
disclose
an
electrochemical
dearomative
spirocyclization
N-acyl
sulfonamides
a
continuous-flow
cell.
reaction
simple
without
external
catalysts
or
supporting
electrolytes,
in-cluding
decagram-scale
synthesis.
The Journal of Organic Chemistry,
Journal Year:
2023,
Volume and Issue:
88(19), P. 13610 - 13621
Published: Sept. 11, 2023
An
electrophilic
spirocyclization
of
N-benzylacrylamides
with
N-halosuccinimides
(NXS)
as
the
halogenating
reagents
has
been
developed.
This
reaction
is
carried
out
at
room
temperature
under
simple
conditions
without
relying
on
metal
reagents,
photochemistry,
or
electrochemistry,
providing
a
fast
and
efficient
route
to
synthesize
wide
variety
4-halomethyl-2-azaspiro[4.5]decanes
satisfactory
yields.
The
approach
further
highlighted
through
gram-scale
synthesis
diverse
transformations
spiro
products.
Chemical Science,
Journal Year:
2024,
Volume and Issue:
15(8), P. 2827 - 2832
Published: Jan. 1, 2024
Efficient
control
over
several
possible
reaction
pathways
of
free
radicals
is
the
chemical
basis
their
highly
selective
transformations.
Among
various
competing
pathways,
sulfonimidyl
generated
from
electrolysis
2-alkynylbenzenesulfonamides
undergo
cascade
migratory
or
Tetrahedron Chem,
Journal Year:
2024,
Volume and Issue:
9, P. 100055 - 100055
Published: Jan. 14, 2024
This
review
concentrates
on
our
research
into
the
discovery
of
novel
ynone-based
dearomative
spirocyclisation
processes,
whilst
placing
new
chemistry
context
existing
knowledge.
The
genesis
programme,
development
efficient
synthetic
routes
to
prepare
natural
products
spirobacillene
A
(1)
and
B
(2),
utilised
indole
ynones.
stimulated
a
much
wider
study
explore
reactivity
ynones
in
processes
more
generally.
Routes
generate
wide
range
spirocycles
were
subsequently
developed,
with
reactions
tethered
indoles,
benzofurans,
benzisoxazoles,
pyrroles,
pyridines,
isoquinolines,
pyrazines,
cyclic
ketimines,
anisoles
all
discussed
herein,
these
initiated
by
catalytic
Ag(I),
Cu(II),
Pd(0),
photolysis
many
other
reagents.
Asymmetric
variants
some
are
also
discussed,
as
is
further
elaboration
spirocyclic
give
carbazoles,
quinolones,
polycycles
useful
building
blocks.
Finally,
applications
methodology
product
synthesis
(e.g.
A,
lasubine
II
indolizidine
209D)
described.
Organic Letters,
Journal Year:
2023,
Volume and Issue:
25(32), P. 6001 - 6005
Published: Aug. 7, 2023
An
electrochemical
facilitated
three-component
trifluoromethylation/spirocyclization
reaction
of
N-(arylsulfonyl)acrylamides,
CF3SO2Na,
and
H2O
has
been
developed.
Without
the
requirement
chemical
oxidants,
a
number
unexplored
trifluoromethylated
4-azaspiro[4.5]decanes
were
obtained
in
satisfactory
yields
under
mild
conditions.
This
work
provides
new
synthetic
strategy
for
fluorine-containing
spirocyclic
compounds
shows
perspective
reactivity
study
N-(arylsulfonyl)acrylamides.
The
reaction
of
N
-propiolyl-benzimidazole
with
aliphatic
carboxylic
acids
in
the
presence
ammonium
persulfate
leading
to
pyrrolo-benzimidazolones
is
presented.
Organic Letters,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 6, 2025
An
electro-oxidative
formal
(3
+
3)
annulation
of
1,3,5-triazinanes
with
enamines
toward
multisubstituted
1,2-dihydropyrimidines
is
reported.
This
metal-free
mild
protocol
offers
wide
functional
group
tolerance,
and
heterocycles
an
unexplored
molecular
scaffold
were
constructed
in
excellent
yields.
Mechanistically,
the
electro-oxidation
triazinane
nucleophilic
reactivity
enamine
result
a
concomitant
annulation-fragmentation
process,
leading
to
six-membered
heterocyclic
product.
The Journal of Organic Chemistry,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 9, 2025
An
unprecedented
approach
involving
radical-mediated
sulfonylation/dearomative
ipso-annulation
of
N-(methyl-2-phenylacetate)propiolamides
using
arylsulfonyl
radical,
generated
from
aryl
diazonium
salt
in
the
presence
DABSO,
is
developed.
This
strategy
provides
uniquely
substituted
3-sulfonyl
azaspiro[4.5]decatrienones
good
yields.
The
developed
has
also
been
extended
fruitfully
to
3-thiocyano
aza-spirocycles
through
domino
thiocyanation/dearomative
ipso-annulation.
The Journal of Organic Chemistry,
Journal Year:
2023,
Volume and Issue:
88(23), P. 16485 - 16496
Published: Nov. 9, 2023
Till
date,
the
ipso-cyclization
of
propiolamides
is
limited
to
provide
azaspiro[4,5]decatrienones.
Herein,
we
present
first
example
ipso-carbocyclization,
leading
azaspiro[5,5]-undecatrienones
from
N-propiolyl-2-arylbenzimidazoles,
involving
both
radical-based
and
electrophilic
reactions.
This
report
establishes
an
access
a
wide
range
chalcogenated
(SCN/SCF3/SePh)
benzimidazo-fused
azaspiro[5,5]undecatrienones
in
good
yields.
