Here
we
present
an
enantioselective
intramolecular
hydroamination
reaction
of
o-aminophenyl-1,3-enynes
via
cooperative
catalysis
Pd(0)
and
chiral
phosphoric
acid.
This
approach
enables
the
efficient
construction
N–N/C–N
axially
stereogenic
indoles
with
broad
skeletal
diversity
high
levels
enantioselectivity
in
a
completely
atom-economic
manner.
Mechanistic
studies
indicate
that
protonation
alkyne
moiety
π-Lewis
base
activation
is
favored,
phosphate
counteranion
plays
crucial
role
controlling
atroposelectivity
ring-closure
step.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(7), С. 4727 - 4740
Опубликована: Фев. 8, 2024
Cooperative
bimetallic
catalysis
to
access
novel
reactivities
is
a
powerful
strategy
for
reaction
development
in
transition-metal-catalyzed
chemistry.
Particularly,
elucidation
of
the
evolution
two
transition-metal
catalysts
and
understanding
their
roles
dual
are
among
most
fundamental
goals
catalysis.
Herein,
three-component
terminal
alkyne,
diazo
ester,
an
allylic
carbonate
was
successfully
developed
via
cooperative
Cu/Rh
with
Xantphos
as
ligand,
providing
highly
efficient
1,5-enynes
all-carbon
quaternary
center
that
can
be
used
immediate
synthetic
precursors
complex
cyclic
molecules.
Notably,
Meyer–Schuster
rearrangement
involved
reactions
using
propargylic
alcohols,
resulting
unprecedented
acylation–allylation
carbenes.
Mechanistic
studies
suggested
course
Cu(I)
species
might
aggregate
some
types
Cu
clusters
nanoparticles
(NPs),
while
Rh(II)2
precursor
dissociate
mono-Rh
species,
wherein
NPs
proposed
responsible
alkynylation
carbenes
work
cooperation
Xantphos-coordinated
dirhodium(II)
or
Rh(I)-catalyzed
alkylation.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 7, 2025
The
ever-increasing
demand
in
chemical
biology
and
medicinal
research
requires
the
development
of
new
synthetic
methods
for
rapid
construction
libraries
heterocycles
from
simple
raw
materials.
In
this
context,
utilization
primary
amines
or
H2O
as
N-
O-sources
assembly
a
heterocyclic
ring
skeleton
is
highly
desirable
viewpoint
atom-
step-economy.
Herein,
we
describe
efficient
three-component
reaction
diazo,
allylic
diacetates,
commercially
available
anilines
(or
H2O)
to
access
structurally
diverse
pyrrolidine
tetrahydrofuran
derivatives.
This
formal
[1
+
1
3]
annulation
features
high
efficiency,
good
yields,
broad
functional
group
compatibility,
making
it
versatile
robust
platform
(formal)
synthesis
several
important
bioactive
molecules.
Mechanistic
studies
suggested
that
dirhodium–palladium
bimetallic
relay
catalysis
should
play
key
role
successive
steps
current
reaction,
including
sequential
carbene
insertion
into
X–H
bond
double
substitutions,
thus
allowing
building
up
molecular
complexity
these
ACS Central Science,
Год журнала:
2022,
Номер
8(5), С. 581 - 589
Опубликована: Апрель 20, 2022
Para-selective
C-H
functionalization
of
free
phenols
by
metal
carbenoids
is
rather
challenging
due
to
the
generally
more
favorable
competing
O-H
insertion.
Herein,
with
use
combination
Rh(II)
and
a
Xantphos
ligand
as
catalyst,
novel
multicomponent
reaction
phenols,
diazoesters,
allylic
carbonates
was
successfully
developed,
affording
wide
variety
phenol
derivatives,
bearing
an
all-carbon
quaternary
center
synthetically
useful
unit.
This
likely
occur
through
tandem
process
carbene-induced
para-selective
functionalization,
followed
Rh(II)/Xantphos-catalyzed
allylation.
The
distinctive
reactivity
than
insertion
for
carbenoid
intermediate,
combined
features
excellent
functional
group
compatibility,
high
atom
step
economy,
ease
in
further
diversification
products,
might
render
this
protocol
highly
attractive
facile
unprotected
phenols.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(42)
Опубликована: Авг. 4, 2022
Abstract
We
reported
herein
an
iridium/silver/acid
ternary
catalytic
system
to
access
bisbenzannulated
[6,6]‐spiroketals
in
high
efficiency
with
generally
diastereo‐
and
enantioselectivities
(up
>20
:
1
dr,
>99
%
ee).
In
this
procedure,
readily
available
o
‐alkynylacetophenones
undergo
cycloisomerization
generate
isochromenes
situ
that
participate
stereoselective
allylation/spiroketalization
sequence
2‐(1‐hydroxyallyl)phenols.
Meanwhile,
2‐(1‐hydroxyallyl)anilines
were
also
compatible
cascade
reaction,
furnishing
structurally
novel
[6,6]‐spiroaminals
good
diastereoselectivities
(8
1–12
dr)
excellent
(98
%–>99
Moreover,
experimental
studies
theoretical
calculations
performed
illustrate
the
reaction
mechanism
stereochemistry.
ACS Catalysis,
Год журнала:
2022,
Номер
12(22), С. 14185 - 14193
Опубликована: Ноя. 4, 2022
Herein,
we
report
an
achiral
dirhodium
complex
and
chiral
phosphoric
acid
cooperatively
catalyzed
asymmetric
three-component
reaction
of
enynal
with
alcohol
imine,
affording
α-furyl-β-amino
carboxylates
in
good
to
high
yields
generally
excellent
stereoselectivity.
The
successful
introduction
as
a
carbene
precursor
this
provides
expeditious
track
prepare
furan
derivatives
adjacent
quaternary
tertiary
stereocenters.
starting
materials
are
stable
readily
available,
the
method
features
100%
atom
economy
bond-formation
efficiency.
This
is
highly
enantioselective
gem-difunctionalization
metal
generated
situ
from
enynal.
These
products
could
be
smoothly
converted
polycyclic
frameworks
drug-conjugated
through
different
cycloaddition
reactions.
Organic Chemistry Frontiers,
Год журнала:
2023,
Номер
10(12), С. 3080 - 3109
Опубликована: Янв. 1, 2023
Chiral
phosphates
have
successfully
been
used
as
ligands
in
asymmetric
metal-catalysis.
This
Minireview
discusses
the
most
recent
examples,
including
main-group
catalysis,
transition-metal
catalysis
and
by
rare-earth
metals.
Abstract
Multicomponent
reactions
provide
an
excellent
approach
toward
quaternary
carbon
centres
utilizing
convergent
chemical
in
a
highly
selective
manner
under
one‐pot
conditions.
The
reactivity
of
substrates
and
metal
catalysts
is
carefully
controlled,
precluding
the
formation
side‐products.
In
this
context,
transition
catalyzed
onium
ylides
generated
via
diazo
precursors
nucleophiles
with
third
component
(an
electrophile)
have
garnered
significant
attention.
Using
allylic
precursor
as
electrophilic
partner
provides
opportunities
to
construct
all‐carbon
centres.
Furthermore,
presence
allyl
fragment
multicomponent
product
serves
pivotal
handle
for
carrying
out
subsequent
modifications.
Several
recent
studies
employed
Rh,
Pd,
dual
Rh/Pd
catalytic
systems
involving
alkylation
that
proceed
synergistic
or
relay
pathway.
Although
not
significantly
successful,
few
cases,
asymmetric
induction
achieved
through
chiral
phosphoric
acids
phosphine
ligands.
Limited
substrate
catalyst
scope
underlying
mechanistic
complexities
posed
formidable
challenges,
slowing
advancement
reactions.
This
review
details
using
readily
available
like
compounds,
carbonates,
(R‐OH,
R‐NH
2
,
etc
.)
forming
complex
organic
compounds.
Our
primary
objective
discuss
issues
may
facilitate
progress
field.
A
robust
and
practical
difluoroalkylation
synthon,
α,α-difluoroenol
species,
which
generated
in
situ
from
trifluoromethyl
diazo
compounds
water
the
presence
of
dirhodium
complex,
is
disclosed.
As
compared
to
presynthesized
difluoroenoxysilane
formed
difluoroenolate
under
basic
conditions,
this
difluoroenol
intermediate
displayed
versatile
reactivity,
resulting
dramatically
improved
enantioselectivity
mild
conditions.
demonstrated
catalytic
asymmetric
aldol
reaction
Mannich
reactions
with
ketones
or
imines
chiral
organocatalysts,
quinine-derived
urea,
phosphoric
acid
(CPA),
respectively,
relay
catalysis
strategy
provides
an
effective
platform
for
applying
fluorination
chemistry.
Moreover,
method
features
a
novel
1,2-difunctionalization
process
via
installation
carbonyl
motif
alkyl
group
on
two
vicinal
carbons,
complementary
protocol
metal
carbene
gem-difunctionalization
reaction.
