Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(30)
Опубликована: Май 25, 2023
Abstract
Hydrofunctionalization
of
alkynes
is
one
the
most
efficient
ways
to
access
axially
chiral
styrenes
with
open‐chained
olefins.
While
great
advances
have
been
achieved
for
1‐alkynylnaphthalen‐2‐ols
and
analogues,
atroposelective
hydrofunctionalization
unactivated
internal
lags.
Herein
we
reported
a
platinum‐catalyzed
hydrosilylation
first
time.
With
monodentate
TADDOL‐derived
phosphonite
L1
used
as
ligand,
various
were
in
excellent
enantioselectivities
high
E
‐selectivities.
Control
experiments
showed
that
N
H‐arylamide
groups
significant
effects
on
both
yields
could
act
directing
groups.
The
potential
utilities
products
shown
by
transformations
amide
motifs
products.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(17)
Опубликована: Янв. 26, 2022
Abstract
The
first
highly
atroposelective
construction
of
N−N
axially
chiral
indole
scaffolds
was
established
via
a
new
strategy
de
novo
ring
formation.
This
makes
use
the
organocatalytic
asymmetric
Paal–Knorr
reaction
well‐designed
N
‐aminoindoles
with
1,4‐diketones,
thus
affording
‐pyrrolylindoles
in
high
yields
and
excellent
atroposelectivities
(up
to
98
%
yield,
96
ee).
In
addition,
this
is
applicable
for
synthesis
bispyrroles
97
More
importantly,
such
heterocycles
can
be
converted
into
organocatalysts
applications
catalysis,
some
molecules
display
potent
anticancer
activity.
work
not
only
provides
but
also
offers
members
atropisomer
family
promising
synthetic
medicinal
chemistry.
Nature Communications,
Год журнала:
2022,
Номер
13(1)
Опубликована: Янв. 10, 2022
Abstract
Axially
chiral
styrenes
bearing
a
axis
between
sterically
non-congested
acyclic
alkene
and
an
aryl
ring
are
difficult
to
prepare
due
low
rotational
barrier
of
the
axis.
Disclosed
here
is
N
-heterocyclic
carbene
(NHC)
catalytic
asymmetric
solution
this
problem.
Our
reaction
involves
ynals,
sulfinic
acids,
phenols
as
substrates
with
NHC
catalyst.
Key
steps
involve
selective
1,4-addition
anion
acetylenic
acylazolium
intermediate
sequential
E
-selective
protonation
set
up
affords
axially
product
>
99:1
e.r
.,
20:1
/
Z
selectivity,
excellent
yields.
The
sulfone
carboxylic
ester
moieties
in
our
styrene
products
common
bioactive
molecules
catalysis.
Tetrahedron Chem,
Год журнала:
2022,
Номер
1, С. 100009 - 100009
Опубликована: Март 1, 2022
Axial
chirality
is
historically
epitomized
by
biaryl
compounds
containing
rotationally
impeded
aryl-aryl
linkage.
As
the
field
of
atroposelective
catalysis
advances,
synthesis
and
application
less
common
scaffolds
such
as
alkenes
have
now
come
to
fore.
The
manifestation
axial
in
aryl
was
hypothesized
1928
first
resolution
achieved
nearly
a
decade
later.
However,
catalytic
asymmetric
construction
axially
chiral
open-chain
appeared
only
2017
which
ushered
renewed
focus
on
these
structures.
In
principle,
possess
an
alkene
group
tethered
at
one
end
stereogenic
axis,
greatly
reduces
overall
rigidity.
To
date,
atropisomers
with
C
(vinyl)-C
(aryl)
(vinyl)-heteroatom
bond
been
reported.
Considering
rapid
growth
synthetic
utility
alkenes,
this
review
intends
provide
historical
overview
discusses
new
developments.
It
hope
that
timely
discussion
would
motivate
continued
nascent
field.
ACS Catalysis,
Год журнала:
2023,
Номер
13(4), С. 2565 - 2575
Опубликована: Фев. 6, 2023
We
present
herein
an
unprecedented
stereoselective
synthesis
of
triaryl-2-pyrones
with
monoaxial
or
contiguous
diaxes
from
readily
available
starting
materials.
This
N-heterocyclic
carbene
catalysis
method
adopts
atroposelective
annulation
2-aryketones
ynals
under
oxidative
conditions.
The
includes
the
construction
one
two
axes
in
a
single
operation,
achieves
step
economy,
and
affords
axially
chiral
moderate
to
good
yields,
high
excellent
enantioselectivities.
DFT
calculations
relative
energies
stereoisomers
rotational
barriers
were
performed.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Апрель 16, 2024
Abstract
The
past
century
has
witnessed
a
large
number
of
reports
on
the
Z
/
E
isomerization
alkenes.
However,
vast
majority
them
are
still
limited
to
di-
and
tri-substituted
stereospecific
tetrasubstituted
alkenes
remains
be
an
underdeveloped
area,
thus
lacking
in
stereodivergent
synthesis
axially
chiral
Herein
we
report
atroposelective
alkene
analogues
by
asymmetric
allylic
substitution-isomerization,
followed
their
via
triplet
energy
transfer
photocatalysis.
In
this
regard,
N
-vinylquinolinones
is
achieved
efficiently.
Mechanistic
studies
indicate
that
benzylic
radical
generation
distribution
two
key
factors
for
preserving
enantioselectivities
compounds.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
61(1)
Опубликована: Окт. 22, 2021
Axially
chiral
open-chain
olefins
represent
an
underexplored
class
of
platform.
In
this
report,
two
classes
tetrasubstituted
axially
acyclic
have
been
accessed
in
excellent
enantioselectivity
and
regioselectivity
via
C-H
activation
(hetero)arenes
assisted
by
a
migratable
directing
group
en
route
to
coupling
with
sterically
hindered
alkynes.
The
indoles
bearing
N-aminocarbonyl
afforded
C-N
acrylamides
the
assistance
racemic
zinc
carboxylate
additive.
DFT
studies
suggest
β-nitrogen
elimination-reinsertion
pathway
for
migration.
Meanwhile,
employment
N-phenoxycarboxamide
delivered
C-C
enamides
migration
oxidizing
group.
Experiments
that
both
cases
(hetero)arene
substrate
adopts
well-defined
orientation
during
activation,
which
turn
determines
disposition
alkyne
migratory
insertion.
Synthetic
applications
representative
are
demonstrated.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
61(7)
Опубликована: Ноя. 30, 2021
A
new
class
of
axially
chiral
styrene-based
thiourea
tertiary
amine
catalysts,
which
have
unique
characteristics
such
as
an
efficient
synthetic
route,
multiple
elements,
and
activating
groups,
has
been
rationally
designed.
These
catalysts
proven
to
be
organocatalysts,
enabling
the
chemo-,
diastereo-,
enantioselective
(2+4)
cyclization
2-benzothiazolimines
with
homophthalic
anhydrides
in
good
yields
(up
96
%)
excellent
stereoselectivities
(all
>95:5
dr,
up
98
%
ee).
More
importantly,
theoretical
calculations
elucidated
important
role
styrene
moiety
controlling
both
reactivity
enantioselectivity.
This
work
not
only
represents
first
design
catalytic
asymmetric
2-benzothiazolimines,
but
also
gives
in-depth
understanding
organocatalysts.