Angewandte Chemie,
Год журнала:
2023,
Номер
135(21)
Опубликована: Март 18, 2023
Abstract
Metal‐polarized
aza‐
ortho
‐quinone
methides
(aza‐
o
‐QMs)
are
a
unique
and
efficient
handle
for
azaheterocycle
synthesis.
Despite
great
achievements,
the
potential
of
these
reactive
intermediates
has
not
yet
been
fully
exploited,
especially
new
reaction
modes.
Herein,
we
disclosed
an
unprecedented
dearomatization
process
metal‐polarized
‐QMs,
affording
transient
dearomatized
spiroaziridine
intermediates.
Based
on
this
serendipity,
accomplished
three
sequential
dearomatization‐rearomatization
reactions
benzimidazolines
with
aza‐sulfur
ylides,
enabling
divergent
synthesis
bis‐nitrogen
heterocycles
high
efficiency
flexibility.
Moreover,
experimental
theoretical
studies
were
performed
to
explain
proposed
mechanisms
observed
selectivity.
Further
cellular
evaluation
dibenzodiazepine
products
identified
hit
compound
antitumor
drugs.
Organic Letters,
Год журнала:
2023,
Номер
25(8), С. 1274 - 1279
Опубликована: Фев. 17, 2023
A
copper-catalyzed
diastereo-
and
enantioselective
decarboxylative
[3
+
2]
cyclization
reaction
of
alkyne-substituted
cyclic
carbamates
with
azlactones
has
been
established.
range
optically
pure
γ-butyrolactams
bearing
two
vicinal
tetrasubstituted
carbon
stereocenters
were
obtained
in
high
yields
good
to
excellent
stereoselectivities
(up
99%
yield,
99:1
dr,
ee).
This
is
the
first
example
asymmetric
synthesis
containing
sterically
congested
via
a
pathway.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
unknown
Опубликована: Сен. 18, 2024
A
Pd-catalyzed
asymmetric
higher-order
dipolar
cycloaddition
between
allenyl
carbonates
and
azadienes
is
achieved
by
exploiting
novel
alkylidene-π-allyl-Pd
dipoles.
This
research
provides
a
modular
platform
for
the
synthesis
of
challenging
chiral
endocyclic
allenes
bearing
medium-sized
heterocyclic
motif
centrally
stereocenter
in
good
yields
with
high
enantio-
diastereoselectivities
(29
examples,
up
to
97%
yield,
97:3
er
>19:1
dr).
Experimental
computational
studies
elucidate
possible
reaction
mechanism
observed
stereochemical
results.
Based
on
mechanistic
understanding,
new
π-propargyl-Pd
dipole
was
designed
further
extend
success
higher
order
strategy
10-membered
alkynes
from
propargyl
(13
98%
yield
94.5:5.5
er).
Organic Letters,
Год журнала:
2024,
Номер
26(15), С. 3310 - 3315
Опубликована: Апрель 8, 2024
A
catalyst
system
consisting
of
a
chiral
phosphoramidite
ligand
and
Pd2(dba)3·CHCl3
causes
the
decarboxylation
5-vinyloxazolidine-2,4-diones
to
generate
amide-containing
aza-π-allylpalladium
1,3-dipole
intermediates,
which
are
capable
triggering
dearomatization
3-nitroindoles
for
diastereo-
enantioselective
[3+2]
cycloaddition,
leading
formation
series
highly
functionalized
pyrroloindolines
containing
three
contiguous
stereogenic
centers
with
excellent
results
(up
99%
yield,
88:12
dr,
96%
ee).
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(21)
Опубликована: Март 18, 2023
Metal-polarized
aza-ortho-quinone
methides
(aza-o-QMs)
are
a
unique
and
efficient
handle
for
azaheterocycle
synthesis.
Despite
great
achievements,
the
potential
of
these
reactive
intermediates
has
not
yet
been
fully
exploited,
especially
new
reaction
modes.
Herein,
we
disclosed
an
unprecedented
dearomatization
process
metal-polarized
aza-o-QMs,
affording
transient
dearomatized
spiroaziridine
intermediates.
Based
on
this
serendipity,
accomplished
three
sequential
dearomatization-rearomatization
reactions
benzimidazolines
with
aza-sulfur
ylides,
enabling
divergent
synthesis
bis-nitrogen
heterocycles
high
efficiency
flexibility.
Moreover,
experimental
theoretical
studies
were
performed
to
explain
proposed
mechanisms
observed
selectivity.
Further
cellular
evaluation
dibenzodiazepine
products
identified
hit
compound
antitumor
drugs.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 17, 2025
Trans-cycloalkenes
are
abundant
in
bioactive
natural
products
and
have
been
used
as
powerful
tools
chemical
biology
drug
discovery.
However,
strategies
for
the
modular
synthesis
of
trans-cycloalkenes,
especially
planar-chiral
medium-sized
ones,
with
high
efficiency
selectivity,
still
remain
elusive.
Herein,
we
report
a
Pd-catalyzed
asymmetric
[7
+
2]
cyclization
strategy
to
address
this
challenge.
As
result,
two
types
trans-cyclononenes
bearing
all-carbon
chiral
quaternary
stereocenters
produced
up
85%
yield,
>99%
ee,
>19:1
dr
(42
examples).
The
key
success
is
maintenance
trans-2H
configuration
π-allyl-Pd
species
along
unusual
linear
selectivity
during
H-bond-assisted
process.
In
addition,
conversion
planar
chirality
central
its
application
selective
bioimaging
cancer
cells
via
bioorthogonal
reaction
were
performed
demonstrate
synthetic
value
methodology.
ACS Catalysis,
Год журнала:
2025,
Номер
unknown, С. 5796 - 5805
Опубликована: Март 25, 2025
The
transition
metal-catalyzed
asymmetric
[n
+
2]
cycloaddition
reaction
with
oxy-substituted
ketene
intermediates
remains
a
synthetic
challenge
due
to
the
limited
availability
of
suitable
precursors.
Herein,
we
report
visible-light-driven,
palladium-catalyzed
[4
vinyl
benzoxazinanones
siloxyketene
intermediates,
generating
structurally
diverse
chiral
quinolinone
derivatives
satisfactory
diastereo-
and
enantioselectivities.
transient
generation
siloxyketenes
from
α-ketoacylsilylanes
through
visible-light-induced
Brook
rearrangement
is
important
for
success
present
cycloaddition.
13C-labeling
experiments
reveal
pathway
involving
[1,3]-silyl
migration
process.
side
arm
effects
BOX
ligand
silyl
steric
hindrance
α-ketoacylsilanes
play
crucial
roles
in
stereoselectivity
control,
theoretical
calculations
provide
insights
into
stereochemical
outcome
reaction.
