Angewandte Chemie,
Journal Year:
2019,
Volume and Issue:
131(17), P. 5795 - 5799
Published: Feb. 27, 2019
Abstract
Dearomatization
of
anthranils
with
vinylcyclopropanes
(VCPs)
by
Pd‐catalyzed
[4+3]
cyclization
reaction
has
been
realized.
In
the
presence
a
catalytic
amount
borane
as
an
activator,
bridged
cyclic
products
were
obtained
in
good
to
excellent
yields
stereoselectivities.
By
introducing
chiral
PHOX
ligand
(
L5
),
asymmetric
dearomatization
reactions
proceeded
enantioselectivity.
Borane
plays
key
role
for
reactivity,
likely
owing
formation
borane–anthranil
complex
which
confirmed
NMR
experiments.
Organic Letters,
Journal Year:
2018,
Volume and Issue:
21(1), P. 330 - 334
Published: Dec. 26, 2018
The
first
highly
stereoselective
intermolecular
catalytic
asymmetric
dearomatization
(CADA)
of
α-naphthols
through
C-C
formation
and
the
allylic
naphthols
by
chiral
organocatalysis
have
been
achieved.
These
new
complete
atom-economic
reactions
provide
enantioriched
α-
β-naphthalenones
bearing
an
all-carbon
quaternary
center.
ACS Catalysis,
Journal Year:
2018,
Volume and Issue:
8(11), P. 10888 - 10894
Published: Oct. 22, 2018
The
organocatalyzed
asymmetric
dearomative
addition
of
phenols
to
indol-2-ones
generated
in
situ
from
3-bromooxindoles
was
reported.
This
methodology
leads
the
efficient
construction
a
series
enantioenriched
3,3′-disubstituted
oxindoles
bearing
vicinal
all-carbon
quaternary
stereocenters
via
dearomatization
process
under
mild
reaction
conditions.
Additionally,
representative
large-scale
reactions
and
related
transformations
dearomatized
products
reveal
potential
synthetic
utility
this
protocol.
Organic Letters,
Journal Year:
2019,
Volume and Issue:
21(14), P. 5452 - 5456
Published: June 28, 2019
Organocatalytic
asymmetric
dearomatization
of
3-nitroindoles
and
3-nitrobenzothiophenes
by
reaction
with
ethyl
4-mercapto-2-butenoate
has
been
developed.
A
range
chiral
tetrahydrothiopheneindolines
tetrahydrothiophenebenzothiophenes
bearing
three
contiguous
stereocenters
are
obtained
in
high
yields
good
diastereoselectivities
excellent
enantioselectivities.
This
is
the
first
example
thiol-triggered
catalytic
3-nitrobenzothiophenes.
Angewandte Chemie,
Journal Year:
2018,
Volume and Issue:
130(8), P. 2156 - 2160
Published: Jan. 13, 2018
Abstract
A
stereodivergent
synthesis
of
tetrahydrofuroindoles
through
palladium‐catalyzed
asymmetric
dearomative
formal
[3+2]
cycloaddition
nitroindoles
with
epoxybutenes
was
developed.
The
polarity
the
solvent
found
to
play
a
key
role
in
diastereoselectivity.
In
toluene,
good
excellent
yields
(70–99
%),
diastereoselectivity
(87/13‐>95/5
d.r.),
and
enantioselectivity
(85/15–94/6
e.r.)
were
obtained,
regardless
properties
substituents
on
nitroindoles.
acetonitrile,
different
diastereoisomer
produced
(75–98
%)
stereoselectivity
(78/22–93/7
d.r.,
93/7–99/1
e.r.).
Mechanistic
studies
conducted
illustrate
origin
diastereodivergency.
kinetic
experiments
indicate
that
rate‐determining
step
this
reaction
is
solvents.
ESI‐MS
also
support
existence
palladium
complex
intermediates
catalytic
cycle
reaction.
Angewandte Chemie,
Journal Year:
2019,
Volume and Issue:
131(16), P. 5476 - 5480
Published: Feb. 12, 2019
Abstract
Over
the
past
years,
metal‐catalyzed
dearomative
cycloaddition
of
3‐nitroindoles
and
2‐nitrobenzofurans
have
emerged
as
a
powerful
protocol
to
construct
chiral
fused
heterocyclic
rings.
However,
organocatalytic
reaction
these
two
classes
heteroarenes
has
become
long‐standing
challenging
task.
Herein,
we
report
first
example
phosphine‐catalyzed
asymmetric
[3+2]‐cycloadditio
2‐nitrobenzofurans,
which
provide
new,
facile,
efficient
for
synthesis
2,3‐fused
cyclopentannulated
indolines
dihydrobenzofurans
by
reacting
with
allenoates
MBH
carbonates,
respectively
through
[3+2]‐cycloaddition.
The Journal of Organic Chemistry,
Journal Year:
2018,
Volume and Issue:
83(8), P. 4730 - 4738
Published: March 29, 2018
An
enantioselective
sulfenylation
of
β-naphthols
has
been
developed
for
the
first
time
using
a
newly
synthesized
cinchona-derived
thiourea
as
catalyst
and
N-(arylthio)
succinimide
(or
phthalimide)
an
electrophilic
sulfur
source.
Various
enantioenriched
naphthalenones
with
S-containing
all-substituted
stereocenter
were
prepared
via
dearomatization
strategy
under
mild
reaction
conditions.
Chinese Journal of Chemistry,
Journal Year:
2018,
Volume and Issue:
36(10), P. 925 - 928
Published: July 28, 2018
Abstract
An
asymmetric
fluorinative
dearomatization
reaction
of
tryptophol
derivatives
was
developed
via
chiral
anion
phase‐transfer
catalysis.
Various
fluorinated
furoindolines
were
obtained
in
moderate
to
excellent
yields
and
enantioselectivity
the
presence
Selectfluor.
The
preliminary
mechanistic
studies
suggested
existence
an
situ
formed
boronic
ester
plays
a
critical
role
determining
enantioselectivity.
This
method
features
facile
introduction
fluorine
atom
highly
enantioselective
manner
construction
two
contiguous
quaternary
stereogenic
centers.
Organic Letters,
Journal Year:
2019,
Volume and Issue:
21(18), P. 7315 - 7319
Published: Sept. 2, 2019
The
first
example
of
copper-catalyzed
enantioselective
dearomative
azidation
β-naphthols
using
a
readily
available
N3-transfer
reagent
is
reported.
A
series
2-hydroxy-1-naphthamides
bearing
complex
N-substituent
were
converted
to
the
corresponding
products
in
high
yields
with
up
96%
ee,
and
chiral
1-azido-2-hydroxy-1-naphthoates
obtained
90%
ee
under
mild
reaction
conditions.
azides
could
be
further
transformed
into
1,2,3-triazoles
smoothly
via
"click"
reaction.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(20), P. 7865 - 7872
Published: Sept. 28, 2021
A
palladium-catalyzed
enantioselective
Heck
cyclization/dearomatization
cascade
via
capturing
the
cyclized
π-allylpalladium
intermediate
by
β-naphthols
is
reported,
which
provides
a
new
strategy
for
construction
of
chiral
indole-terpenoid
frameworks.
This
method
affords
indole-functionalized
β-naphthalenone
compounds
bearing
an
all-carbon-substituted
quaternary
center
in
excellent
yields
(up
to
92%)
and
enantioselectivities
94%
ee).
In
addition,
utility
this
showcased
gram-scale
syntheses
diverse
transformations
dearomatized
products.
Chinese Journal of Chemistry,
Journal Year:
2020,
Volume and Issue:
38(7), P. 683 - 689
Published: March 30, 2020
Summary
of
main
observation
and
conclusion
Asymmetric
arylative
dearomatization
reactions
para
‐aminophenols
are
realized
by
a
Pd‐catalyst
consisting
TADDOL
(α,α,α',α'‐tetraaryl‐2,2‐disubstituted
1,3‐dioxolane‐4,5‐dimethanol)‐derived
chiral
phosphoramidite
ligand.
The
tetracyclic
products
bearing
the
key
skeleton
Erythrina
alkaloids
afforded
in
reasonable
yields
(up
to
73%)
with
good
excellent
enantioselectivity
97%
ee).
Concise
total
synthesis
(–)‐3‐demethoxyerythratidinone
is
achieved
employing
this
method
as
step.
