Angewandte Chemie,
Год журнала:
2023,
Номер
136(2)
Опубликована: Ноя. 13, 2023
Abstract
Herein
we
report
the
first
enantioselective
total
synthesis
of
(+)‐incargranine
A,
in
nine
steps.
The
was
enabled
by
an
intramolecular
organocatalysed
desymmetrising
Michael
addition
a
malonamate
ester
to
linked
dienone
substrate
that
established
pivotal
stereocentres
with
excellent
enantio‐
and
complete
diastereoselectivity.
Furthermore,
key
hemiaminal
intermediate
accessed
developing
iridium‐catalysed
reductive
cyclisation,
scope
this
transformation
explored
produce
range
bicyclic
motifs.
Once
installed,
motif
used
initiate
biomimetic
cascade
access
natural
product
directly
single
step.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(37)
Опубликована: Июнь 25, 2024
Abstract
Chiral
allylic
alcohols
are
highly
prized
in
synthetic
chemistry
due
to
their
versatile
reactivity
stemming
from
both
alkenyl
and
hydroxyl
functionalities.
While
the
Nozaki–Hiyama–Kishi
(NHK)
reaction
is
a
widely
used
method
for
synthesis
of
alcohols,
it
suffers
drawbacks
such
as
use
toxic
chromium
salts,
high
amounts
metal
reductants,
poor
enantiocontrol.
To
address
these
limitations,
we
present
novel
approach
involving
metallaphotoredox‐catalyzed
asymmetric
NHK
production
chiral
alcohols.
This
marries
(pseudo)halides
with
aldehydes,
leveraging
synergistic
blend
nickel
catalyst
photocatalyst.
innovative
technique
enables
oxidative
addition
insertion
just
using
nickel,
diverging
significantly
conventional
pathway
mediated
by
salts.
The
adoption
this
methodology
holds
immense
promise
crafting
spectrum
intricate
compounds,
particularly
those
significance
pharmaceuticals.
Detailed
experimental
investigations
have
shed
light
on
metallaphotoredox
process,
further
enhancing
our
understanding
enabling
advancements.
Total
synthesis
of
melonine
was
accomplished.
A
cycloheptene
unit
and
a
quinoline
were
connected
via
Stille
coupling.
The
core
cleaved
with
thiophosgene
to
liberate
the
arylamine
moiety.
Oxidative
intramolecular
aziridination,
followed
by
nucleophilic
attack
moiety
aziridine
ring,
constructed
characteristic
cyclic
system
trans-1,2-diamine
structure.
Stereoselective
hydrogenation
formation
piperidine
ring
led
melonine.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
63(2)
Опубликована: Ноя. 13, 2023
Herein
we
report
the
first
enantioselective
total
synthesis
of
(+)-incargranine
A,
in
nine
steps.
The
was
enabled
by
an
intramolecular
organocatalysed
desymmetrising
Michael
addition
a
malonamate
ester
to
linked
dienone
substrate
that
established
pivotal
stereocentres
with
excellent
enantio-
and
complete
diastereoselectivity.
Furthermore,
key
hemiaminal
intermediate
accessed
developing
iridium-catalysed
reductive
cyclisation,
scope
this
transformation
explored
produce
range
bicyclic
motifs.
Once
installed,
motif
used
initiate
biomimetic
cascade
access
natural
product
directly
single
step.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(41), С. 22335 - 22340
Опубликована: Окт. 4, 2023
The
first
enantioselective
total
syntheses
of
(-)-caulamidine
D
(5)
and
(-)-isocaulamidine
(6)
were
accomplished.
Their
absolute
configurations
unambiguously
elucidated
through
X-ray
crystallography.
isolated
natural
samples
both
5
6
are
determined
to
be
the
TFA
salts
instead
neutral
forms.
It
took
16
steps
(longest
linear
sequence)
divergently
access
following
a
unified
strategy.
key
reactions
include
(1)
development
application
an
asymmetric
Meerwein-Eschenmoser-Claisen
rearrangement
construct
challenging
C10,
C23
consecutive
stereocenters
(2)
cascade
6-exo-dig/6-exo-tet
amine/nitrile
cyclization
reaction.
Organic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(11), С. 3186 - 3195
Опубликована: Янв. 1, 2024
Three
typical
substrates
for
the
Mannich
reaction,
p
-anisidine,
aldehyde,
and
a
nucleophile,
did
not
afford
predictable
linear
base
under
an
aerobic
copper
oxidation
condition,
but
rendering
2,2-disubstituted
indolin-3-one
product.
ACS Catalysis,
Год журнала:
2024,
Номер
14(12), С. 9207 - 9216
Опубликована: Июнь 3, 2024
Highly
enantioselective
[1,3]
sigmatropic
rearrangement
represents
a
grand
challenge
in
asymmetric
organocatalysis.
Herein,
we
disclose
chiral
phosphoramide
(R)-NPA-Cy
mediated
of
2-alkoxy
indoles
to
access
diverse
array
highly
enantio-enriched
oxindoles.
The
catalyst
displayed
good
high
control
(89–99%
ee)
while
maintaining
efficiency
(up
99%
yield).
More
than
60
examples
were
demonstrated.
Mechanistic
and
computational
studies
revealed
that
the
C–O
bond
cleavage
indole
ether
substrates
can
generate
contact
ion
pairs
stabilized
by
via
noncovalent
interactions.
Different
catalyst–substrate
interactions
observed
competing
transition
states
leading
enantiomeric
oxindoles,
serving
as
major
factor
determining
enantioselectivity.
In
addition,
this
reaction
was
applied
total
syntheses
both
enantiomers
(−)-
(+)-fusaspoid
A
only
five
steps
reassigned
their
rotation
values,
correcting
original
misassignments.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
64(1)
Опубликована: Сен. 26, 2024
Geometrically
defined
allylic
alcohols
with
SE,
SZ,
RE
and
RZ
stereoisomers
serve
as
valuable
intermediates
in
synthetic
chemistry,
attributed
to
the
stereoselective
transformations
enabled
by
alkenyl
hydroxyl
functionalities.
When
an
ideal
scenario
presents
itself
four
distinct
potential
products,
simultaneous
control
vicinal
stereochemistry
a
single
step
would
offer
direct
pathway
any
desired
stereoisomer.
Here,
we
unveil
metallaphotoredox
migration
strategy
access
stereodefined
through
vinylic
C-H
activation
aldehydes.
This
method
harnesses
chiral
nickel
catalyst
concert
photocatalyst
enable
1,4-Ni
using
readily
accessible
2-vinyl
iodoarenes
starting
materials.
The
efficacy
of
this
methodology
is
highlighted
precise
construction
all
bearing
analogous
substituents
efficient
synthesis
key
en
route
Myristinin
family.
Experimental
computational
studies
have
shed
light
on
pivotal
aspects
including
synergy
metal
catalysis
photocatalysis,
driving
forces
behind
migration,
determination
absolute
configuration
addition
process.
Chemistry - A European Journal,
Год журнала:
2023,
Номер
30(11)
Опубликована: Ноя. 22, 2023
In
this
work,
a
straightforward
synthesis
of
C3-N1'
bisindolines
is
achieved
by
formal
umpolung
strategy.
The
protocols
were
tolerant
wide
variety
substituents
on
the
indole
and
indoline
ring.
addition,
could
be
converted
to
indole-indolines
C3-N1'-bisindoles.
Also,
we
have
successfully
synthesized
(±)-rivularin
A
through
biomimetic
late-stage
tribromination
as
key
step.
