Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
60(43), С. 23187 - 23192
Опубликована: Авг. 26, 2021
Abstract
An
unprecedented
enantioselective
synthesis
of
spiro‐γ‐lactams
via
a
sequential
C−H
olefination/asymmetric
[4+1]
spirocyclization
under
simple
Co
II
/chiral
spiro
phosphoric
acid
(SPA)
binary
system
is
reported.
A
range
biologically
important
are
obtained
with
high
levels
enantioselectivity
(up
to
98
%
ee
).
The
concise,
asymmetric
an
aldose
reductase
inhibitor
was
successfully
achieved.
Notably,
contrast
previous
reports
that
relied
on
the
use
cyclopentadienyl
or
its
derivatives
(achiral
Cp*,
Cp
tBu
,
chiral
x
)
ligated
III
complexes
requiring
tedious
steps
prepare,
cheap
and
commercially
available
cobalt(II)
acetate
tetrahydrate
used
as
efficient
precatalyst.
Journal of the American Chemical Society,
Год журнала:
2020,
Номер
143(2), С. 604 - 611
Опубликована: Дек. 31, 2020
Arene
dearomatization
is
a
straightforward
method
for
converting
an
aromatic
feedstock
into
functionalized
carbocycles.
Enantioselective
dearomatizations
of
chemically
inert
arenes,
however,
are
quite
limited
and
underexplored
relative
to
those
phenols
indoles.
We
developed
diazo-free
generation
silver-carbene
species
from
ynamide
applied
it
the
nonactivated
arenes.
Transiently
generated
norcaradiene
could
be
trapped
by
intermolecular
[4
+
2]
cycloaddition,
synthesizing
polycycles
with
five
consecutive
stereogenic
centers.
This
protocol
constitutes
first
highly
enantioselective
reaction
based
on
species.
Mechanistic
investigations
revealed
followed
two
different
classes
pericyclic
reactions,
as
well
origin
chemo-
enantioselectivity.
Angewandte Chemie International Edition,
Год журнала:
2020,
Номер
59(18), С. 7193 - 7197
Опубликована: Фев. 19, 2020
Abstract
Dearomative
annulation
of
indoles
has
emerged
as
a
powerful
tool
for
the
preparation
polycyclic
indoline‐based
alkaloids.
Compared
with
well‐established
methods
towards
five‐membered‐ring‐fused
indolines,
six‐membered‐ring‐fused
indolines
are
rarely
accessed
under
thermal
conditions.
Herein,
dearomative
[4+2]
between
different
is
developed
through
an
electrochemical
pathway.
This
transformation
offers
remarkably
regio‐
and
stereoselective
route
to
highly
functionalized
pyrimido[5,4‐
b
]indoles
oxidant‐
metal‐free
Notably,
this
approach
maintains
excellent
functional‐group
tolerance
can
be
extended
modification
tactic
pharmaceutical
research.
Preliminary
mechanism
studies
indicate
that
electrooxidation
proceeds
radical–radical
cross‐coupling
indole
radical
cation
N‐centered
generated
in
situ.
Angewandte Chemie International Edition,
Год журнала:
2020,
Номер
59(10), С. 4121 - 4130
Опубликована: Янв. 8, 2020
Abstract
The
construction
of
diverse
sp
3
‐rich
skeletal
ring
systems
is
importance
to
drug
discovery
programmes
and
natural
product
synthesis.
Herein,
we
report
the
photocatalytic
2,7‐diazabicyclo[3.2.1]octanes
(bridged
1,3‐diazepanes)
via
a
reductive
diversion
Minisci
reaction.
fused
tricyclic
proposed
form
radical
addition
C4
position
4‐substituted
quinoline
substrates,
with
subsequent
Hantzsch
ester‐promoted
reduction
dihydropyridine
intermediate
which
undergoes
in
situ
two‐electron
closure
bridged
diazepane
architecture.
A
wide
scope
N‐arylimine
derivatives
was
demonstrated
good
efficiency
observed
sterically
congested
all‐carbon
quaternary
centers.
Computational
experimental
mechanistic
studies
provided
insights
into
reaction
mechanism
regioselectivity/diastereoselectivity.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
60(13), С. 7036 - 7040
Опубликована: Янв. 15, 2021
Abstract
Herein
we
report
visible‐light‐induced
intramolecular
double
dearomative
cycloaddition
of
arenes.
Compared
with
the
well‐known
photodimerization
arenes
under
ultraviolet
irradiation,
current
reactions
are
carried
out
mild
conditions
and
feature
wide
substrate
scope.
A
large
array
structurally‐diverse
polycyclic
indoline
derivatives
is
afforded
in
high
yields
(up
to
98
%)
exclusive
diastereoselectivity
(>20:1
dr)
via
[4+2]
or
[2+2]
pathway.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
60(43), С. 23187 - 23192
Опубликована: Авг. 26, 2021
Abstract
An
unprecedented
enantioselective
synthesis
of
spiro‐γ‐lactams
via
a
sequential
C−H
olefination/asymmetric
[4+1]
spirocyclization
under
simple
Co
II
/chiral
spiro
phosphoric
acid
(SPA)
binary
system
is
reported.
A
range
biologically
important
are
obtained
with
high
levels
enantioselectivity
(up
to
98
%
ee
).
The
concise,
asymmetric
an
aldose
reductase
inhibitor
was
successfully
achieved.
Notably,
contrast
previous
reports
that
relied
on
the
use
cyclopentadienyl
or
its
derivatives
(achiral
Cp*,
Cp
tBu
,
chiral
x
)
ligated
III
complexes
requiring
tedious
steps
prepare,
cheap
and
commercially
available
cobalt(II)
acetate
tetrahydrate
used
as
efficient
precatalyst.
