Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 1, 2025
A
new
class
of
binaphthyl
unit-enhanced
pyridine-oxazoline
ligands
was
developed
to
promote
the
Pd-catalyzed
enantioselective
intramolecular
7-exo
aminoacetoxylation
unactivated
biaryl
alkenes.
Biaryl-bridged
7-membered
N-heterocycles
bearing
a
chiral
center
were
obtained
in
good
yields
with
excellent
enantioselectivities
(up
99:1
er).
Computational
investigations
on
series
biaryl-bridged
rings
provided
insights
into
rotational
barrier
potentially
unit
by
substituent
effect
including
heteroatom,
protecting
group,
and
center.
The
kinetic
resolution
racemic
axially
biaryls
via
alkenes
has
also
been
achieved,
affording
previously
inaccessible
both
axis,
as
well
amino
alcohols.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(29), P. 19621 - 19628
Published: May 13, 2024
For
nearly
60
years,
significant
research
efforts
have
been
focused
on
developing
strategies
for
the
cycloaddition
of
bicyclobutanes
(BCBs).
However,
higher-order
and
catalytic
asymmetric
BCBs
long-standing
formidable
challenges.
Here,
we
report
Pd-catalyzed
ligand-controlled,
tunable
cycloadditions
divergent
synthesis
bridged
bicyclic
frameworks.
The
dppb
ligand
facilitates
formal
(5+3)
vinyl
oxiranes,
yielding
valuable
eight-membered
ethers
with
scaffolds
in
100%
regioselectivity.
Cy-DPEphos
promotes
selective
hetero-[2σ+2σ]
to
access
pharmacologically
important
2-oxabicyclo[3.1.1]heptane
(O-BCHeps).
Furthermore,
corresponding
O-BCHeps
94–99%
ee
has
achieved
using
chiral
(S)-DTBM-Segphos,
representing
first
cross-dimerization
two
strained
rings.
obtained
are
promising
bioisosteres
ortho-substituted
benzenes.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(26)
Published: April 20, 2024
Photoinduced
Pd-catalyzed
bisfunctionalization
of
butadienes
with
a
readily
available
organic
halide
and
nucleophile
represents
an
emerging
attractive
method
to
assemble
versatile
alkenes
bearing
various
functional
groups
at
the
allylic
position.
However,
enantiocontrol
and/or
diastereocontrol
in
C-C
or
C-X
bond-formation
step
have
not
been
solved
due
open-shell
process.
Herein,
we
present
cascade
asymmetric
dearomatization
reaction
indoles
via
photoexcited
1,2-biscarbonfunctionalization
1,3-butadienes,
wherein
control
on
both
electrophile
part
is
achieved
for
first
time
photoinduced
butadienes.
This
delivers
structurally
novel
chiral
spiroindolenines
two
contiguous
stereogenic
centers
high
diastereomeric
ratios
(up
>20
:
1
dr)
good
excellent
enantiomeric
97
3
er).
Experimental
computational
studies
mechanism
confirmed
radical
pathway
involving
excited-state
palladium
catalysis.
The
alignment
non-covalent
interactions
between
substrate
catalyst
were
found
be
essential
stereocontrol.
Chemical Society Reviews,
Journal Year:
2024,
Volume and Issue:
53(19), P. 9560 - 9581
Published: Jan. 1, 2024
Chiral
amine
scaffolds
are
among
the
most
important
building
blocks
in
natural
products,
drug
molecules,
and
functional
materials,
which
have
prompted
chemists
to
focus
more
on
their
synthesis.
Among
accomplishments
chiral
synthesis,
transition-metal-catalyzed
enantioselective
C-N
cross-coupling
is
considered
one
of
efficient
protocols.
This
approach
combines
traditional
C(sp
ACS Catalysis,
Journal Year:
2025,
Volume and Issue:
unknown, P. 5796 - 5805
Published: March 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.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(24), P. 16892 - 16901
Published: June 6, 2024
The
development
of
a
catalytic
method
for
stereogenic
carbon
center
formation
holds
immense
significance
in
organic
synthesis.
Transition-metal-catalyzed
cross-coupling
reaction
has
been
regarded
as
straightforward
and
efficient
tool
stereoselectively
forging
C–C
bond.
Nevertheless,
the
creation
acyclic
all-carbon
quaternary-containing
vicinal
stereocenters
remains
notoriously
challenging
within
domain
chemistry
despite
their
prominence
various
bioactive
small
molecules.
Herein,
we
describe
palladium-catalyzed
asymmetric
multicomponent
trisubstituted
alkene
with
aryl
diazonium
salts
arylboronic
acids
to
realize
tertiary-quaternary
centers
high
regio-,
distereo-,
enantioselectivity.
Specifically,
precise
manipulation
stereoconfiguration
alkenes
enables
divergent
stereoselective
reaction,
thus
allowing
facile
construction
all
four
enantiomers.
Harnessing
ligand-swap
strategy
involving
chiral
bisoxazoline
an
achiral
fumarate
individually
accelerates
enantioselective
migratory
insertion
reductive
elimination
step
process,
supported
by
density
functional
theory
(DFT)
calculations,
obviating
requirement
neighboring
directing
group
internal
olefin
skeleton.