Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(8), P. 4808 - 4818
Published: Feb. 16, 2023
The
textbook
alkene
halogenation
reaction
establishes
straightforward
access
to
vicinal
dihaloalkanes.
However,
a
robust
catalytic
method
for
dihalogenizing
electron-deficient
olefins
in
an
enantioselective
manner
is
still
under
development,
and
its
mechanism
remains
controversial.
Herein,
we
disclose
efficient
regio-,
anti-diastereo-,
dibromination,
bromochlorination,
dichlorination
reactions
of
enones
catalyzed
by
chiral
N,N'-dioxide/Yb(OTf)3
complex.
With
the
combination
electrophilic
halogen
halide
salts
as
halogenating
agents,
array
homo-
heterodihalogenated
derivatives
achieved
moderate
good
enantioselectivities.
Moreover,
DFT
calculations
reveal
that
novel
triplet
halo-radical
pylon
intermediate
probable
accounting
exclusive
regio-
anti-diastereoselectivity.
Accounts of Chemical Research,
Journal Year:
2022,
Volume and Issue:
55(12), P. 1763 - 1781
Published: June 8, 2022
ConspectusOver
recent
decades,
N-sulfonylhydrazones
have
attracted
significant
attention
in
academic
and
industrial
contexts
owing
to
their
ease
of
preparation,
versatile
reactivity,
high
stability,
practicality.
In
particular,
the
use
as
precursors
for
diazo
compounds
has
paved
way
innovative
original
organic
reactions
that
are
otherwise
difficult
achieve.
Three
key
developments
noteworthy
history
N-sulfonylhydrazone
chemistry:
(1)
Bamford
Stevens
initially
disclosed
application
N-tosylhydrazones
a
source
1952;
(2)
Aggarwal
co-workers
investigated
N-tosylhydrazone
salts
sulfur
ylide-mediated
asymmetric
epoxidation
aziridination
2001;
(3)
Barluenga,
Valdés
first
reported
Pd-catalyzed
cross-coupling
with
2007,
thus
introducing
direct
carbene
transfer
reactions.
past
2
synthetic
exploration
chemistry
increased
remarkably.
N-Tosylhydrazones
most
commonly
used
N-sulfonylhydrazones,
but
they
not
easy
decompose
normally
need
relatively
temperatures
(e.g.,
90–110
°C).
Temperature,
reaction
parameter,
influence
on
selectivity
scope
reactions,
especially
enantioselectivity.
addressed
this
issue
by
using
achieved
limited
number
method
is
greatly
because
must
be
freshly
prepared
or
stored
dark
at
−20
°C
prior
use.
Hence,
easily
decomposable
those
capable
decomposing
low
temperature,
should
open
up
new
opportunities
development
chemistry.
Since
2014,
our
group
worked
toward
goal
eventually
identified
N-2-(trifluoromethyl)benzenesulfonylhydrazone
(i.e.,
N-triftosylhydrazone)
an
efficient
surrogate
can
−40
°C.
This
allowed
us
carry
out
range
challenging
transformations
broaden
applications
some
known
great
relevance.In
Account,
we
report
achievements
N-triftosylhydrazones
On
basis
types,
such
categorized
(i)
C(sp3)–H
insertion
(ii)
defluorinative
fluoroalkyl
N-triftosylhydrazones,
(iii)
cycloaddition
alkenes
alkynes,
(iv)
Additional
Doyle–Kirmse
rearrangements
isocyanides
(ours)
benzyl
chlorides
(from
Xia)
also
summarized
Account
concerning
miscellaneous
terms
efficiency,
selectivity,
functional
tolerance,
generally
superior
traditional
decomposition.
Mechanistic
investigations
theoretical
calculations
provide
insights
into
both
mechanisms
origin
selectivity.
We
hope
will
inspire
broad
interest
promote
progress
N-sulfonylhydrazones.
Chemical Science,
Journal Year:
2022,
Volume and Issue:
13(42), P. 12290 - 12308
Published: Jan. 1, 2022
Catalytic
asymmetric
sigmatropic
rearrangements
induced
by
chiral
metal
catalysis
have
been
intensively
explored.
This
review
summarizes
recent
significant
advances,
mainly
involving
[3,3],
[2,3]
and
[1,3]-rearrangements.
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(48), P. 22140 - 22149
Published: Nov. 22, 2022
Photocatalysis
opens
up
a
new
window
for
carbonyl
chemistry.
Despite
multitude
of
photochemical
reactions
compounds,
visible
light-induced
catalytic
asymmetric
transformations
remain
elusive
and
pose
formidable
challenge.
Accordingly,
the
development
simple,
efficient,
economic
systems
is
ideal
pursuit
chemists.
Herein,
we
report
an
enantioselective
radical
photoaddition
to
ketones
through
Lewis
acid-enabled
photoredox
catalysis
wherein
in
situ
formed
chiral
N,N'-dioxide/Sc(III)-ketone
complex
serves
as
temporary
photocatalyst
trigger
single-electron
transfer
oxidation
silanes
generation
nucleophilic
species,
including
primary,
secondary,
tertiary
alkyl
radicals,
giving
various
enantioenriched
aza-heterocycle-based
alcohols
good
excellent
yields
enantioselectivities.
The
results
electron
paramagnetic
resonance
(EPR)
high-resolution
mass
spectrum
(HRMS)
measurements
provided
favorable
evidence
stereocontrolled
addition
process
involved
this
reaction.
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(29)
Published: April 21, 2022
Abstract
The
ubiquity
of
sulfur‐containing
molecules
in
biologically
active
natural
products
and
pharmaceuticals
has
long
attracted
synthetic
chemists
to
develop
efficient
strategies
towards
their
synthesis.
strategy
direct
α‐C(sp
3
)−H
modification
sulfides
provides
a
streamlining
access
complex
molecules.
Herein,
we
report
photoinduced
chemo‐,
site‐
stereoselective
functionalization
using
isatins
as
the
photoredox
reagent
coupling
partner
catalyzed
by
chiral
gallium(III)‐
N,N
′‐dioxide
complex.
reaction
proceeds
through
verified
single‐electron
transfer
(SET)
mechanism
with
high
efficiency,
excellent
functional
group
tolerance,
well
broad
substrate
scope.
Importantly,
this
cross‐coupling
protocol
is
highly
selective
for
late‐stage
methionine‐related
peptides,
regardless
inherent
structural
similarity
complexity
diverse
residues.
Organic Chemistry Frontiers,
Journal Year:
2023,
Volume and Issue:
10(14), P. 3676 - 3683
Published: Jan. 1, 2023
Privileged
Feng
ligands
feature
designer
N
,
’-dioxide
amides
with
a
unique
conformational
and
coordination
flexibility.
This
highlight
summarizes
the
increasingly
profound
impact
of
on
modern
catalytic
asymmetric
synthesis.
European Journal of Organic Chemistry,
Journal Year:
2022,
Volume and Issue:
2022(44)
Published: Oct. 21, 2022
Abstract
Cyclopropanes
are
one
of
the
most
important
strained
rings
existing
in
various
pharmaceutical
products
and
secondary
metabolites.
They
also
widely
used
total
synthesis
natural
products,
medicinal
chemistry,
materials
science.
In
past
years,
photochemical
cyclopropanation
has
been
gradually
developed
as
a
robust
attractive
synthetic
method
to
prepare
diverse
cyclopropane
backbones.
this
review,
we
summarize
recent
advances
visible
light‐mediated
synthesis,
especially
using
carbene
transfer
strategy
photocatalytic
radical
reactions.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(10)
Published: Jan. 14, 2023
[2,3]-Sigmatropic
rearrangement
reaction
involving
sulfonium
ylide
(Doyle-Kirmse
reaction)
generated
from
metal
carbenes
represents
one
of
the
powerful
methods
for
construction
C(sp3
)-S
and
C-C
bonds.
Although
significant
advances
have
been
achieved,
asymmetric
versions
via
generation
ylides
rarely
reported
to
date,
they
so
far
limited
diazo
compounds
as
carbene
precursors.
Here,
we
describe
a
copper-catalyzed
enantioselective
Doyle-Kirmse
azide-ynamide
cyclization,
leading
practical
divergent
assembly
an
array
chiral
[1,4]thiazino[3,2-b]indoles
bearing
quaternary
carbon
stereocenter
in
generally
moderate
excellent
yields
enantioselectivities.
Importantly,
this
protocol
unique
catalytic
non-diazo
approach
unprecedented
[2,3]-sigmatropic
α-imino
carbenes.
Nature Communications,
Journal Year:
2023,
Volume and Issue:
14(1)
Published: March 17, 2023
With
the
fast
development
of
synthetic
chemistry,
introduction
functional
group
into
organic
molecules
has
attracted
increasing
attention.
In
these
reactions,
difunctionalization
unsaturated
bonds,
traditionally
with
one
nucleophile
and
electrophile,
is
a
powerful
strategy
for
chemical
synthesis.
this
work,
we
develop
different
path
electrochemical
oxidative
diazo
compounds
two
nucleophiles.
Under
metal-free
external
oxidant-free
conditions,
series
structurally
diverse
heteroatom-containing
hardly
synthesized
by
traditional
methods
(such
as
high-value
alkoxy-substituted
phenylthioacetates,
α-thio,
α-amino
acid
derivatives
well
α-amino,
β-amino
derivatives)
are
obtained
in
synthetically
useful
yields.
addition,
procedure
exhibits
mild
reaction
excellent
functional-group
tolerance
good
efficiency
on
large-scale
Importantly,
protocol
also
amenable
to
key
intermediate
bioactive
simple
practical
process.
Organic Chemistry Frontiers,
Journal Year:
2023,
Volume and Issue:
11(2), P. 597 - 630
Published: Nov. 23, 2023
This
review
highlights
the
recent
progress
in
electrochemical
difunctionalization
of
alkenes
and
alkynes
involving
C–S/Se
bond
formation
to
access
organochalcogen
frameworks.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(28), P. 15611 - 15618
Published: July 5, 2023
Asymmetric
epoxidation
of
alkenes
catalyzed
by
nonheme
chiral
Mn–O
and
Fe–O
catalysts
has
been
well
established,
but
Co–O
for
the
purpose
remain
virtually
undeveloped
due
to
oxo
wall.
Herein
is
first
reported
a
cobalt
complex
realize
enantioselective
cyclic
acyclic
trisubstituted
using
PhIO
as
oxidant
in
acetone,
wherein
tetra-oxygen-based
N,N′-dioxide
with
sterically
hindered
amide
subunits
plays
crucial
role
supporting
formation
intermediate
electrophilic
oxygen
transfer.
Mechanistic
studies,
including
HRMS
measurements,
UV–vis
absorption
spectroscopy,
magnetic
susceptibility,
DFT
calculations,
were
carried
out,
confirming
species
quartet
Co(III)-oxyl
tautomer.
The
mechanism
origin
enantioselectivity
also
elucidated
based
on
control
experiments,
nonlinear
effects,
kinetic
calculations.