Angewandte Chemie,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Nov. 7, 2024
Abstract
A
strategy
for
the
photosensitized
[2+2]‐cycloaddition
between
styrenyl
dihaloboranes
and
unactivated
allylamines
to
access
cyclobutylboronates
with
control
of
stereochemistry
regiochemistry
is
presented.
The
success
reaction
relies
on
temporary
coordination
in
situ
generated
amines
under
mild
conditions.
In
addition,
cyclobutanes
varying
substitution
patterns
have
been
prepared
using
N
‐heterocycles
as
directing
group.
Manipulation
C−B
bond
allows
synthesis
a
diverse
class
from
simple
precursors.
Moreover,
these
reactions
lead
complex
heteroaromatic
compounds,
which
significant
utility
medicinal
chemistry.
Finally,
dearomative
[4+2]‐cycloaddition
naphthalenes
boron‐enabled
tethering
has
also
uncovered
synthesize
3‐dimensional
borylated
building
blocks.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(14), P. 10142 - 10149
Published: March 27, 2024
Saturated
bicyclic
compounds
make
up
a
valuable
class
of
building
blocks
in
the
development
agrochemicals
and
pharmaceuticals.
Here,
we
present
synthesis
borylated
bicyclo[2.1.1]hexanes
via
crossed
[2
+
2]-cycloaddition.
Due
to
presence
C–B
bond,
variety
structures
can
be
easily
prepared
that
are
not
accessible
by
other
methods.
Moreover,
rare
photo-ene
reaction
is
also
disclosed,
allowing
for
diastereoselective
trisubstituted
cyclopentanes.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(8), P. 5366 - 5374
Published: Feb. 14, 2024
Two
enantioselective
approaches
to
synthesize
chiral
skipped
diboronate
compounds
have
been
developed,
relying
on
copper-catalyzed
one-pot
asymmetric
ring-opening
diboration
of
arylidenecyclopropanes.
A
wide
range
arylidenecyclopropanes
react
smoothly
with
HBpin
in
the
presence
CuOAc
and
(R)-DTBM-Segphos,
affording
1,4-diboronates
high
enantioselectivity
(up
99%
ee).
Meanwhile,
a
variety
selectively
B2pin2
(S,S)-Ph-BPE
sequential
addition
MeOH,
providing
1,3-diboronates
98%
These
enantioenriched
1,3-
can
undergo
various
enantiospecific
transformations
minimal
loss
their
enantiopurity.
Mechanistic
studies
reveal
that
these
two
processes
start
CuH-catalyzed
hydroboration
form
mixture
Z/E-homoallyl
boronate
intermediates,
which
subsequently
second
or
Cu-Bpin-catalyzed
protoboration
produce
1,3-diboronates,
respectively.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(38), P. 20755 - 20760
Published: Aug. 31, 2023
Activation
of
enantiomerically
enriched
tertiary
alkylboronic
esters
with
adamantyllithium
generated
in
situ
enables
stereoretentive
boron-to-copper
transmetalation.
The
resulting
alkylcopper
species
can
undergo
cross-coupling
reactions
an
array
electrophiles
to
furnish
synthetically
useful
compounds
bearing
quaternary
stereocenters.
DFT
calculations
the
transmetalation
process
provide
insights
for
reactivity
and
selectivity.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(44), P. 23899 - 23904
Published: Oct. 25, 2023
The
first
oxidative
chloro-
and
bromodifluoromethylation
of
phenols
with
(CH3)3SiCF2X
CuX
(X
=
Cl
or
Br)
in
the
presence
Selectfluor
under
mild
reaction
conditions
was
developed.
This
protocol
provided
a
practical
efficient
method
for
synthesis
diverse
range
biologically
valuable
synthetically
challenging
bromodifluoromethyl
aryl
ethers.
Preliminary
mechanistic
studies
suggest
that
this
proceeded
through
difluorocarbene-involved
coupling
process.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(25)
Published: April 19, 2024
The
reaction
regioselectivity
of
gem-difluoroalkenes
is
dependent
on
the
intrinsic
polarity.
Thus,
reversal
addition
remains
a
formidable
challenge.
Herein,
we
described
an
unprecedented
hydrogen
atom
transfer
(HAT)
to
triggered
by
Fe-H
species
for
formation
difluoroalkyl
radicals.
Hydrogenation
in
situ
generated
radicals
gave
difluoromethylated
products.
Mechanism
experiments
and
theoretical
studies
revealed
that
kinetic
effect
irreversible
HAT
process
resulted
this
scenario,
leading
less
stable
α-difluoroalkyl
radical
regioisomer.
On
basis
new
gem-difluoroalkene,
iron-promoted
hydrohalogenation
efficient
synthesis
aliphatic
chlorodifluoromethyl-,
bromodifluoromethyl-
iododifluoromethyl-containing
compounds
was
developed.
Particularly,
novel
provided
large-scale
access
various
iododifluoromethylated
high
value
synthetic
application.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(20), P. 13719 - 13726
Published: May 9, 2024
With
increasing
interest
in
constructing
more
three-dimensional
entities,
there
has
been
growing
cross-coupling
reactions
that
forge
C(sp3)–C(sp3)
bonds,
which
leads
to
additional
challenges
as
it
is
not
just
a
difficult
bond
construct
but
issues
of
stereocontrol
also
arise.
Herein,
we
report
the
stereocontrolled
enantioenriched
boronic
esters
with
racemic
allylic
carbonates
enabled
by
iridium
catalysis,
leading
formation
bonds
single
or
vicinal
stereogenic
centers.
The
method
shows
broad
substrate
scope,
enabling
primary,
secondary,
and
even
tertiary
be
employed,
can
used
prepare
any
four
possible
stereoisomers
coupled
product
chiral
new
method,
combines
simultaneous
enantiospecific
reaction
nucleophile
enantioselective
electrophile
process,
offers
solution
for
stereodivergent
two
C(sp3)
fragments.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(28), P. 18873 - 18878
Published: July 2, 2024
Alkyllithium-activated
organoboronic
esters
are
found
to
undergo
stereospecific
phosphination
with
copper
chloride
and
chlorophosphines.
They
also
react
thiolsulfonate
electrophiles
under
catalysis.
These
reactions
enable
thiolation
of
esters,
which
further
applied
in
preparation
chiral
ligands
biologically
active
molecules.
Science,
Journal Year:
2024,
Volume and Issue:
386(6718), P. 167 - 175
Published: Oct. 10, 2024
Polycyclic
polyprenylated
acylphloroglucinols
(PPAPs)
are
a
class
of
>400
natural
products
with
broad
spectrum
bioactivity,
ranging
from
antidepressant
and
antimicrobial
to
anti-obesity
anticancer
activity.
Here,
we
present
scalable,
regio-,
site-,
enantioselective
catalytic
method
for
synthesis
cyclic
β-prenyl
ketones,
compounds
that
can
be
used
efficient
syntheses
many
PPAPs
in
high
enantiomeric
purity.
The
transformation
is
prenyl
conjugate
addition
β-ketoesters
promoted
by
readily
accessible
chiral
copper
catalyst
involving
an
easy-to-prepare
isolable
organoborate
reagent.
Reactions
reach
completion
just
few
minutes
at
room
temperature.
importance
this
advance
highlighted
the
preparation
intermediates
previously
generate
racemic
PPAPs.
We
also
nemorosonol
(14
steps,
20%
yield)
its
one-step
conversion
another
PPAP,
garcibracteatone
(52%
yield).
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 6, 2025
The
stereocontrolled
C(sp3)–C(sp3)
cross-coupling
represents
a
considerable
challenge
of
great
contemporary
interest.
While
this
has
been
achieved
through
the
reactions
boronate
complexes
with
π-allyl
iridium
complexes,
such
suffered
from
limited
substrate
scope.
We
now
report
that
following
transmetalation
to
organozinc
reagents
enables
previously
unreactive
substrates
engage
in
cross-coupling.
broader
scope
enabled
their
application
synthesis
biologically
active
molecules.
react
stereoinvertive
coupling
pathway
contrast
other
electrophiles
occur
retention
stereochemistry.
reaction
uniquely
combines
enantiospecific
reactivity
an
enantioenriched
organometallic
nucleophile
enantioselective
engagement
racemic
electrophile,
enabling
access
all
stereoisomers.
