The Journal of Organic Chemistry,
Journal Year:
2024,
Volume and Issue:
89(4), P. 2190 - 2199
Published: Jan. 27, 2024
Ketenimines
represent
an
important
class
of
reactive
species,
useful
synthetic
intermediates,
and
synthons.
However,
in
general,
ketenimines
preferentially
undergoes
nucleophilic
addition
reactions
with
hydroxyl
amino
groups,
carbon
functional
groups
remain
a
less
studied
subset
such
systems.
Herein,
we
develop
straightforward
syntheses
pyridin-4(1H)-imines
that
is
achieved
by
cyclization
reacting
enaminone
unit
α-acylketenimine
which
generated
from
the
sulfonyl
azides
terminal
ynones
situ
(CuAAC/Ring
cleavage
reaction).
The
cascade
process
starts
α-C
instead
group,
attacking
electron-deficient
central
ketenimine,
chemoselectivity
unconventional
products
were
formed
intramolecular
cyclization.
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(20)
Published: March 5, 2022
In
recent
years,
asymmetric
catalysis
of
ynamides
has
attracted
much
attention,
but
these
reactions
mostly
constructed
central
chirality,
except
for
a
few
examples
on
the
synthesis
axially
chiral
compounds
which
exclusively
relied
noble-metal
catalysis.
Herein,
facile
access
to
N-heterocycles
enabled
by
Brønsted
acid-catalyzed
5-endo-dig
cyclization
is
disclosed,
represents
first
metal-free
protocol
construction
from
ynamides.
This
method
allows
practical
and
atom-economical
valuable
N-arylindoles
in
excellent
yields
with
generally
enantioselectivities.
Moreover,
organocatalysts
ligands
based
such
N-arylindole
skeletons
are
demonstrated
be
applicable
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(32)
Published: May 24, 2024
Abstract
Synthesis
of
bicyclic
scaffolds
has
gained
significant
attention
in
drug
discovery
due
to
their
potential
mimic
benzene
bioisosteres.
Here,
we
present
a
mild
and
scalable
Sc(OTf)
3
‐catalyzed
[3+2]
cycloaddition
bicyclo[1.1.0]butanes
(BCBs)
with
ynamides,
yielding
diverse
array
polysubstituted
2‐amino‐bicyclo[2.1.1]hexenes
good
excellent
yields.
These
products
offer
valuable
starting
materials
for
the
construction
novel
functionalized
bicyclo[1.1.0]butanes.
Preliminary
mechanistic
studies
indicate
that
reaction
involves
nucleophilic
addition
ynamides
bicyclo[1.1.0]butanes,
followed
by
an
intramolecular
cyclization
situ
generated
enolate
keteniminium
ion.
We
expect
these
findings
will
encourage
utilization
complex
bioisosteres
foster
further
investigation
into
BCB‐based
chemistry.
Angewandte Chemie International Edition,
Journal Year:
2021,
Volume and Issue:
60(52), P. 27164 - 27170
Published: Oct. 21, 2021
Described
herein
is
a
novel
Brønsted
acid
catalyzed
intramolecular
hydroalkoxylation/Claisen
rearrangement,
allowing
the
practical
and
atom-economic
synthesis
of
range
valuable
spirolactams
from
readily
available
ynamides
in
generally
good
to
excellent
yields
with
diastereoselectivities
broad
substrate
scope.
Importantly,
an
unexpected
dearomatization
nonactivated
arenes
heteroaromatic
compounds
involved
this
tandem
sequence.
Moreover,
asymmetric
version
cyclization
was
also
achieved
by
efficient
kinetic
resolution
chiral
phosphoric
catalysis.
In
addition,
[3,3]-rearrangement
shown
be
kinetically
preferred
over
related
[1,3]-rearrangement
theoretical
calculations.
Angewandte Chemie International Edition,
Journal Year:
2021,
Volume and Issue:
61(7)
Published: Dec. 14, 2021
Here,
we
report
a
copper-catalyzed
asymmetric
cascade
cyclization/[1,2]-Stevens-type
rearrangement
via
non-diazo
approach,
leading
to
the
practical
and
atom-economic
assembly
of
various
valuable
chiral
chromeno[3,4-c]pyrroles
bearing
quaternary
carbon
stereocenter
in
generally
moderate
good
yields
with
wide
substrate
scope
excellent
enantioselectivities
(up
99
%
ee).
Importantly,
this
protocol
not
only
represents
first
example
catalytic
[1,2]-Stevens-type
based
on
alkynes
but
also
constitutes
formal
carbene
insertion
into
Si-O
bond.
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(4), P. 1962 - 1970
Published: Jan. 19, 2022
N-CF3
compounds
constitute
valuable
targets
in
medicinal
chemistry.
Extensive
studies
have
been
reported
for
the
preparation
of
through
fluorination
and
trifluoromethylation
N-containing
compounds.
The
development
new
synthetic
methods
from
abundant
easily
available
substrates
is
highly
desirable
but
still
challenging.
Herein,
we
report
design
synthesis
novel
N-Cbz-
N-Boc-N-trifluoromethyl
hydroxylamine
reagents
by
silver-mediated
oxidative
trifluoromethylation.
These
successfully
applied
to
direct
incorporation
a
NCF3
moiety
into
commonly
used
unsaturated
under
photoredox
catalysis.
This
protocol
enables
efficient
regioselective
C-H
trifluoromethylamination
various
(hetero)arenes,
including
complex
bioactive
molecules.
Furthermore,
variety
alkenes,
dienes,
isonitriles
undergo
tandem
trifluoromethylamination/functionalization
delivering
structurally
diverse
N-trifluoromethyl
aliphatic
heteroaromatic
amines.
Notably,
previously
unknown
cyclic
oxazolidinones
oxazolones
were
conveniently
prepared
with
reagents.
diversification
resulting
α-trifluoromethylamino
ketones
afforded
largely
underexplored
N-alkenyl-
N-alkynyl-N-CF3
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(43)
Published: Aug. 17, 2022
Carbonyl
ylides
have
proven
to
be
powerful
synthons
for
the
efficient
construction
of
various
valuable
O-heterocycles,
and
formation
carbonyl
by
reaction
metal
carbenes
with
carbonyls
has
attracted
increasing
attention
over
past
decades.
However,
a
catalyst-controlled
highly
enantioselective
from
is
extremely
challenging.
Herein,
we
report
novel
copper-catalyzed
asymmetric
formal
[2+1]
[4+1]
annulations
diynes
ketones
via
ylides.
Importantly,
this
protocol
not
only
represents
first
example
successful
epoxidation
ylides,
but
also
constitutes
vinyl
cations
compounds.
This
method
leads
divergent,
practical
atom-economical
synthesis
range
chiral
oxiranes
dihydrofurans
in
moderate
excellent
yields
generally
enantioselectivities
diastereoselectivities
remote-stereocontrol
strategy.
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(28)
Published: April 27, 2022
Medium-sized
N,S-heterocycles
have
received
tremendous
interest
due
to
their
biological
activities
and
potential
medical
applications.
However,
asymmetric
synthesis
of
these
compounds
are
extremely
rare.
Described
herein
is
a
catalyst-dependent
[3,3]-sigmatropic
rearrangement
sulfoxide-ynamides,
enabling
divergent
atom-economic
series
valuable
medium-sized
in
moderate
good
yields
with
broad
substrate
scope.
Importantly,
excellent
enantioselectivities
been
achieved
via
an
unprecedented
chirality-transfer.
Moreover,
theoretical
calculations
employed
elucidate
the
origins
stereospecific
[3,3]-rearrangement.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(23)
Published: March 30, 2023
Axially
chiral
biaryls
widely
exist
in
natural
products
and
pharmaceuticals
are
used
as
ligands
catalysts
asymmetric
synthesis.
Compared
to
the
well-established
axially
6-membered
biaryl
skeletons,
examples
of
5-membered
have
been
quite
scarce,
mono-substituted
3-arylpyrrole
atropisomers
not
reported.
Here,
we
disclose
a
copper-catalyzed
atroposelective
diyne
cyclization
for
construction
range
arylpyrrole
good
excellent
yields
with
generally
enantioselectivities
via
oxidation
X-H
insertion
vinyl
cations.
Importantly,
this
protocol
only
represents
first
synthesis
atropisomers,
but
also
constitutes
example
atropisomer
Theoretical
calculations
further
support
mechanism
cation-involved
elucidate
origin
enantioselectivity.