Synergistic catalysis for stereocontrol of prochiral nucleophiles in palladium-catalyzed asymmetric allylic substitution
Science China Chemistry,
Год журнала:
2023,
Номер
66(8), С. 2238 - 2255
Опубликована: Июль 20, 2023
Язык: Английский
Catalytic Stereoselective 1,2-cis-Furanosylations Enabled by Enynal-Derived Copper Carbenes
ACS Catalysis,
Год журнала:
2024,
Номер
14(2), С. 1037 - 1049
Опубликована: Янв. 8, 2024
1,2-cis-Furanosides
are
present
in
various
biomedically
relevant
glycosides,
and
their
stereoselective
synthesis
remains
a
significant
challenge.
In
this
vein,
we
have
developed
approach
to
1,2-cis-furanosylations
using
earth-abundant
copper
catalysis.
This
protocol
proceeds
under
mild
conditions
at
room
temperature
employs
readily
accessible
benchtop
stable
enynal-derived
furanose
donors.
chemistry
accommodates
variety
of
alcohols,
including
primary,
secondary,
tertiary,
as
well
mannosyl
alcohol
acceptors,
which
been
incompatible
with
most
known
methods
furanosylation.
The
resulting
1,2-cis-furanoside
products
exhibit
high
yields
anomeric
selectivity
both
the
ribose
arabinose
series.
Furthermore,
is
independent
C2
oxygen-protecting
group
configuration
starting
donor.
Experimental
evidence
computational
studies
support
our
hypothesis
that
chelation
between
oxygen
donor
an
incoming
nucleophile
responsible
for
observed
1,2-cis-stereoselectivity.
Язык: Английский
Overview of Transition Metal Catalyzed Multicomponent Reactions Based on Trapping of Allylic Electrophiles
ChemCatChem,
Год журнала:
2024,
Номер
16(4)
Опубликована: Янв. 11, 2024
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.
Язык: Английский
Catalytic Orthogonal Glycosylation Enabled by Enynal‐Derived Copper Carbenes
Advanced Synthesis & Catalysis,
Год журнала:
2024,
Номер
366(8), С. 1847 - 1856
Опубликована: Фев. 17, 2024
Abstract
Herein,
we
present
an
approach
for
catalytic
orthogonal
glycosylation
utilizing
earth‐abundant
copper
carbenes.
This
method
operates
under
mild
conditions
and
employs
readily
accessible
starting
materials,
including
benchtop
stable
enynal‐derived
glycosyl
donors,
synthesized
at
the
gram
scale.
The
reaction
accommodates
a
variety
of
acceptors,
primary,
secondary,
tertiary
alcohols.
carbenes
exhibit
remarkable
reactivity
selectivity,
allowing
formation
glycosidic
linkages
with
different
protecting
groups
stereochemical
patterns.
provides
access
to
both
1,2‐
cis
‐
trans
‐glycosidic
linkages.
product
stereoselectivity
is
independent
anomeric
configuration
donor,
which
also
has
widely
used
alkynes
thioglycoside
donors.
An
iterative
synthesis
trisaccharide
further
demonstrates
application
this
reactivity.
Язык: Английский
CuX Dual Catalysis: Construction of Oxazolo[2,3-b][1,3]oxazines via a Tandem CuAAC/Ring Cleavage/[4+2+3] Annulation Reaction
Xiai Luo,
Zhong‐Tao Yang,
Jia Zheng
и другие.
Organic Letters,
Год журнала:
2022,
Номер
24(40), С. 7300 - 7304
Опубликована: Сен. 30, 2022
CuX
as
a
simple
dual
catalyst
strategy
that
promotes
the
tandem
transformations
of
fused
oxazolo[2,3-b][1,3]oxazines
has
been
developed.
Copper
catalyzed
terminal
ynones,
sulfonyl
azides,
and
nitriles
for
CuAAC/ring
cleavage/[4+2]
annulation
reaction,
while
halogen
ring
cleavage
[2+3]
oxiranes
to
form
final
products.
This
study
provides
four-component,
one-pot
synthesizing
complex
heterocycles
from
ingredients
expands
application
CuAAC
in
organic
synthesis.
Язык: Английский
Rh(II)/Pd(0) Dual Catalysis: Interception of Ammonium Ylide with Allyl Palladium to Construct 2,2-Disubstituted Tetrahydroquinoline Derivatives
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(13), С. 9496 - 9504
Опубликована: Июнь 10, 2023
New
synthetic
methods
to
construct
2,2-disubstituted
tetrahydroquinoline
derivatives
are
of
significant
value
in
pharmaceutical
chemistry.
Herein,
a
Rh(II)/Pd(0)
dual-catalyzed
diazo
α-aminoallylation
reaction
has
been
developed
between
allylpalladium(II)
and
ammonium
ylides
derived
from
the
Rh2(OAc)4-mediated
intramolecular
N-H
bond
insertion
compounds,
affording
various
good
yields
up
93%
with
high
chemoselectivities
under
mild
conditions.
A
substrate
scope
investigation
reveals
broad
ester
substituent
tolerance,
control
experiments
provide
basis
for
proposed
mechanism.
Язык: Английский
Synergistic Rh(II)- and Zn(II)-Catalyzed [3 + 3] Annulation of Diazoenals and α-Hydroxy Ketones for the Direct Synthesis of 2H-Pyrans, A Gateway Toward γ-Pyrones
Organic Letters,
Год журнала:
2024,
Номер
26(43), С. 9227 - 9232
Опубликована: Окт. 21, 2024
A
new
synergistic
Rh(II)/Zn(II)-catalyzed
[3
+
3]
annulation
has
been
developed
between
diazoenals
and
α-hydroxy
ketones
enabling
the
direct
synthesis
of
4-formyl-2H-pyrans.
The
reaction
involves
formation
protic
oxonium
ylides
from
highly
electrophilic
Rh-enalcarbenoids
followed
by
Zn-templated
regioselective
intramolecular
aldol
condensation.
Subsequent
investigations
demonstrated
that
4-formyl-2H-pyrans
are
unique
precursors
γ-pyrones.
γ-pyrones
were
obtained
via
Et3N-mediated
oxidative
deformylation.
Further,
triflic-acid-promoted
double
Schmidt
provides
synthetically
important
carboxamide-substituted
4-cyano
2H-pyrans.
Язык: Английский
Rhodium(II)‐Catalyzed Denitrogenative Transformations of N‐Sulfonyl‐1,2,3‐triazoles
European Journal of Organic Chemistry,
Год журнала:
2024,
Номер
unknown
Опубликована: Окт. 21, 2024
Abstract
N
‐Sulfonyl‐1,2,3‐triazoles
are
valuable
precursors
for
the
generation
of
α‐imino
carbene
intermediates
in
presence
metal
catalysts,
especially
rhodium(II)
complexes.
Due
to
electrophilic
and
nucleophilic
nitrogen,
these
reactive
can
easily
be
incorporated
into
many
annulations,
cycloadditions,
C−H
or
O/N/S−H
bond
insertions
functionalization
reactions.
A
large
number
pharmaceutically
important
nitrogen‐based
building
blocks
constructed
via
this
direct
atom‐economical
strategy.
In
review,
we
have
described
transformations
‐sulfonyl‐1,2,3‐triazoles
based
on
intermediates.
Язык: Английский