Chemistry - A European Journal,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 12, 2024
α-Diazoesters
belong
to
significantly
important
carbenoid
precursors
in
synthetic
chemistry.
Diazomethylation-based
difunctionalization
of
alkenes
is
highly
valuable
but
remain
nontrivial.
Herein,
we
reported
a
general
and
modular
approach
for
the
direct
1,2-oxydiazomethylation
through
visible-light
photoredox
catalysis.
This
process
exploits
photocatalyzed
strategy
convert
γ-formyloxyl-α-diazoesters
using
α-diazo
iodonium
salts
as
carbyne
precursors,
featuring
wide
substrate
tolerance
broad
late-stage
diversifications.
Mechanistic
studies
suggest
that
formation
γ-carbocation-tethered
α-diazoesters
plays
crucial
role
trapping
DMF
H
Chinese Journal of Chemistry,
Год журнала:
2023,
Номер
42(2), С. 177 - 189
Опубликована: Сен. 4, 2023
Comprehensive
Summary
Carbonyl
compounds
have
attracted
considerable
attention
due
to
their
extensive
applications
in
drug
discovery.
Furthermore,
they
are
important
synthetic
intermediates
for
the
construction
of
carbon‐carbon
and
carbon‐heteroatom
bonds.
Transition‐metal‐catalyzed
carbonylation
via
insertion
CO
is
one
most
efficient
straightforward
strategies
access
carbonyl
compounds.
However,
transition‐metal‐catalyzed
carbonylative
reactions
require
expensive
toxic
noble‐metal
catalysts.
Therefore,
there
a
growing
demand
exploration
nickel‐catalyzed
earth
abundance
low
cost
nickel.
Compared
with
well‐established
palladium‐catalyzed
reactions,
analogous
transformations
been
relatively
underdeveloped.
This
primarily
because
strongly
binds
nickel,
often
resulting
catalyst
poisoning.
In
recent
years,
some
research
groups
focused
on
using
surrogates
or
NN
2
pincer
nickel
circumvent
formation
Ni(CO)
4
.
Nickel‐catalyzed
has
applied
carbonyl‐containing
compounds,
such
as
ketones,
carboxylic
acids,
thioesters,
acyl
chloride
carboxamides.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(27), С. 14573 - 14580
Опубликована: Июнь 30, 2023
Chiral
N-cyclopropyl
pyrazoles
and
structurally
related
heterocycles
are
prepared
using
an
earth-abundant
copper
catalyst
under
mild
reaction
conditions
with
high
regio-,
diastereo-,
enantiocontrol.
The
observed
N2:N1
regioselectivity
favors
the
more
hindered
nitrogen
of
pyrazole.
Experimental
DFT
studies
support
a
unique
mechanism
that
features
five-centered
aminocupration.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(51)
Опубликована: Окт. 27, 2022
In
contrast
to
previous
approaches
chiral
α-aryl
carboxylic
acids
that
based
on
reactions
using
hazardous
gases,
pressurized
setup
and
mostly
noble
metal
catalysts,
in
this
work,
a
nickel-catalyzed
general,
efficient
highly
enantioselective
carboxylation
reaction
of
racemic
benzylic
(pseudo)halides
under
mild
conditions
atmospheric
CO2
has
been
developed.
A
unique
2,2'-bipyridine
ligand
named
Me-SBpy
featuring
compact
polycyclic
skeleton
enabled
both
high
reactivity
stereoselectivity.
The
utility
method
demonstrated
by
synthesis
various
(30
examples,
up
95
%
yield
99
:
1
er),
including
profen
family
anti-inflammatory
drugs
transformations
the
as
key
intermediates.
Based
mechanistic
experimental
results,
plausible
catalytic
cycle
involving
Ni-complex/radical
equilibrium
Lewis
acid-assisted
activation
proposed.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(34)
Опубликована: Июль 5, 2023
Abstract
The
asymmetric
hydrophosphination
of
cyclopropenes
with
phosphines
is
much
interest
and
importance,
but
has
remained
hardly
explored
to
date
probably
because
the
lack
suitable
catalysts.
We
report
here
diastereo‐
enantioselective
3,3‐disubstituted
by
a
chiral
lanthanocene
catalyst
bearing
C
2
‐symmetric
5,6‐dioxy‐4,7‐
trans
‐dialkyl‐substituted
tetrahydroindenyl
ligands.
This
protocol
offers
selective
efficient
route
for
synthesis
new
family
phosphinocyclopropane
derivatives,
featuring
100
%
atom
efficiency,
good
enantioselectivity,
broad
substrate
scope,
no
need
directing
group.
ACS Catalysis,
Год журнала:
2024,
Номер
14(11), С. 8730 - 8738
Опубликована: Май 21, 2024
A
Cu-catalyzed
cyclopropanation
of
γ-bromocrotonate
derivatives
via
a
hydrocupration–alkylation
sequence
is
described.
This
hydroalkylation
process
good
generality
and
allows
access
to
chiral
cyclopropanes
bearing
aryl,
heteroaryl,
N-indole,
alkenyl,
alkyl
substituents,
all
with
complete
trans-diastereoselectivity,
enantioselectivities
up
>99:1
er,
high
yields.
An
experimental
computational
mechanistic
analysis
was
undertaken,
which
provided
full
understanding
the
factors
affecting
reaction's
diastereo-
enantioselectivity.
More
specifically,
it
found
that
Cu-catalyst
drives
both
conjugate
hydride
addition
alkylation
steps
reaction
enantioselectivity
governed
by
distortion
effects
metal
coordination
sphere
at
diastereomeric
TSs.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Авг. 23, 2024
Atropisomeric
biaryls
bearing
carbonyl
groups
have
attracted
increasing
attention
due
to
their
prevalence
in
diverse
bioactive
molecules
and
crucial
role
as
efficient
organo-catalysts
or
ligands
asymmetric
transformations.
However,
preparation
often
involves
tedious
multiple
steps,
the
direct
synthesis
via
carbonylation
has
scarcely
been
investigated.
Herein,
we
report
an
palladium-catalyzed
enantioconvergent
aminocarbonylation
of
racemic
heterobiaryl
triflates
with
amines
dynamic
kinetic
transformation
(DyKAT).
This
protocol
features
a
broad
substrate
scope
excellent
compatibility
for
rapid
construction
axially
chiral
amides
good
high
yields
enantioselectivities.
Detailed
mechanistic
investigations
discover
that
base
can
impede
intramolecular
hydrogen
bond-assisted
axis
rotation
products,
thus
allowing
success
achieve
enantioselectivity.
Moreover,
achieved
be
directly
utilized
N,N,N-pincer
copper-catalyzed
enantioselective
formation
C(sp3)-N
C(sp3)-P
bonds.
Axially
containing
not
only
exist
various
drug
candidates
but
also
serve
authors
transformation.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
62(4)
Опубликована: Ноя. 25, 2022
We
herein
disclose
a
mild
and
efficient
access
to
chiral
3-azabicyclo[3.1.0]hexanes
via
Pd-catalyzed
asymmetric
5-exo-trig
cyclization/cyclopropanation/carbonylation
of
1,6-enynes.
Various
nucleophiles,
such
as
alcohols,
phenols,
amines
water,
are
well
compatible
with
the
reaction
system.
This
forms
three
C-C
bonds,
two
rings,
adjacent
quaternary
carbon
stereocenters
one
C-O/C-N
bond
excellent
regio-
enantioselectivities.
The
products
could
be
further
functionalized
generate
library
3-azabicyclo[3.1.0]hexane
frameworks.
Chinese Journal of Chemistry,
Год журнала:
2022,
Номер
41(3), С. 294 - 300
Опубликована: Окт. 17, 2022
Comprehensive
Summary
NiH‐catalyzed
multicomponent
reductive
hydrofunctionalization
of
alkenes
is
an
attractive
but
poorly
explored
approach
to
rapidly
increasing
molecular
complexity.
In
this
process,
the
selective
generation
desired
product
can
be
challenging.
Herein,
we
report
that
a
highly
chemo‐,
regio‐
and
enantioselective
hydrocarbonylation
has
been
achieved
using
chloroformate
ester
as
source
CO.
A
wide
range
structurally
diverse
α‐hydroxy
ketones,
privileged
structural
elements
in
bioactive
molecules
useful
building
blocks,
were
obtained
from
such
reactions
with
high
enantiomeric
purity.