Frontiers in Chemistry,
Год журнала:
2022,
Номер
10
Опубликована: Сен. 13, 2022
A
metal-free
catalytic
approach
for
the
remote
C6-functionalization
of
2,3-disubstituted
indoles
has
been
developed.
In
presence
amounts
Brønsted
acid,
β,γ-unsaturated
α-ketoesters
react
with
at
C6
position
selectively.
Under
mild
reaction
conditions,
a
range
C6-functionalized
were
prepared
good
yields
and
excellent
regioselectivity.
This
methodology
provides
concise
efficient
route
synthesis
indole
derivatives.
Abstract
Indole
is
a
significant
structural
moiety
and
functionalization
of
the
C−H
bond
in
indole‐containing
molecules
expands
their
chemical
space,
modifies
properties
and/or
activities.
prenyltransferases
(IPTs)
catalyze
direct
regiospecific
installation
prenyl
moieties
on
indole‐derived
compounds.
IPTs
have
shown
relaxed
substrate
flexibility
enabling
them
to
be
used
as
tools
for
indole
functionalization.
However,
mechanism
by
which
certain
target
specific
carbon
position
not
fully
understood.
Herein,
we
use
structure‐guided
site‐directed
mutagenesis,
vitro
enzymatic
reactions,
kinetics
structural‐elucidation
analogs
verify
key
catalytic
residues
that
control
regiospecificity
all
characterized
C6
IPTs.
The
presented
results
also
demonstrate
substitution
PriB_His312
Tyr
leads
synthesis
prenylated
at
different
positions
than
C6.
This
work
contributes
understanding
how
can
access
challenging
Journal of Heterocyclic Chemistry,
Год журнала:
2022,
Номер
59(6), С. 1116 - 1122
Опубликована: Янв. 9, 2022
Abstract
A
facile
method
for
the
synthesis
of
pyrrolo[2,3‐
j
]phenanthridines
from
indoleanilines
and
aldehydes
in
presence
Brønsted
acid
catalyst
benzoquinone
oxidant
has
been
established.
This
approach
features
excellent
yields,
high
efficiency
a
wide
range
substrate
scope.
Mechanism
studies
exhibited
that
this
reaction
was
cascade
process
including
acid‐catalyzed
condensation
with
aldehydes,
cyclization
oxidative
aromatization.
Molecules,
Год журнала:
2023,
Номер
28(8), С. 3380 - 3380
Опубликована: Апрель 11, 2023
A
green
one-pot
2,3,6-trifunctionalization
of
N-alkyl/aryl
indoles
was
achieved
by
adding
three
equivalents
N-Br
sulfoximine
to
the
indole
solution.
variety
2-sulfoximidoyl-3,6-dibromo
were
prepared
with
38-94%
yields
using
sulfoximines
as
both
brominating
and
sulfoximinating
reagents.
Based
on
results
controlled
experiments,
we
propose
that
a
radical
substitution
involving
3,6-dibromination
2-sulfoximination
occurs
in
reaction
process.
This
is
first
time
one
pot
has
been
achieved.
European Journal of Organic Chemistry,
Год журнала:
2023,
Номер
unknown
Опубликована: Ноя. 16, 2023
Abstract
Herein
we
report
the
first
synthesis
of
tetrahydrocarbazole
embedded
styrene
atropisomers
via
reaction
between
1‐(aryl‐ethynyl)‐naphthalen‐2‐ol
and
2,3,4,9‐tetrahydro‐1
H
‐carbazole.
The
proceeds
through
in
situ
vinylidene
ortho
‐quinone
methide
(VQM)
intermediate
formation.
derivatives
were
obtained
good
to
high
yields
with
diastereoselectivities
a
catalytic
amount
PTSA.
A
asymmetric
version
is
also
reported.
European Journal of Organic Chemistry,
Год журнала:
2023,
Номер
26(11)
Опубликована: Янв. 13, 2023
Abstract
A
metal‐free
1,4‐allylation
of
azadienes
with
allyltrimethylsilanes
catalyzed
by
B(C
6
F
5
)
3
has
been
developed.
The
high
Lewis
acidity,
good
thermal
stability,
and
hydrolytic
stability
the
catalyst
make
this
reaction
efficient
operationally
simple.
In
contrast
to
previously
reported
1,2‐allylation
α,β‐unsaturated
imines,
is
described
here
for
first
time.
Benzofuran‐,
indene‐,
dihydronaphthalene‐,
chromene‐,
benzothiophene‐based
allyl
arylmethanes
have
obtained
in
up
95
%
yield.
Synthesis,
Год журнала:
2023,
Номер
55(21), С. 3417 - 3433
Опубликована: Март 8, 2023
Abstract
Indoles
are
valuable
precursors
in
medicinal,
bioorganic,
and
material
chemistry
particularly
serve
as
a
platform
for
diversity.
However,
the
scope
of
C6-functionalization
indoles
was
limited
until
recently.
In
this
short
review,
we
summarize
developments
reactions
involving
transition-metal-catalyzed
functionalization
Brønsted
Lewis
acid
catalyzed
processes.
The
regioselectivity
is
controlled
by
remote-C–H
activation
hydrogen
bond
formation.
1
Introduction
2
Transition-Metal-Catalyzed
Functionalization
3
Acid-Catalyzed
Processes
4
Conclusion
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(17), С. 3691 - 3696
Опубликована: Янв. 1, 2023
The
construction
of
cyano-substituted
all-carbon
quaternary
centers
via
Brønsted
acid-catalyzed
direct
C6
functionalization
2,3-disubstituted
indoles
with
2,2-diarylacetonitriles
is
reported.
Abstract
We
describe
herein
the
additive‐controlled
divergent
[4+2]
cycloaddition
and
1,4‐Michael
addition
reaction
of
benzofuran‐derived
azadienes
(BDAs)
with
enamides.
An
unprecedented
BDAs
enamide
compounds
was
developed
in
presence
4
Å
MS,
providing
a
variety
structurally
complex
decahydrobenzofuro[3,2‐
b
]quinolines
(13
examples)
moderate
to
excellent
yields
(59–98
%
yields)
single
diastereoisomer
obtained.
While
employing
MgSO
as
desiccant,
chemoselectivity
switched
1,4‐addition
reactions,
leading
wide
range
highly
functionalized
hybrids
benzofurans
(25
25–94
under
mild
conditions.
Abstract
A
novel
and
efficient
method
has
been
established
for
synthesizing
a
variety
of
heterotriarylmethanes
with
good
yields
by
employing
metal-free
self-coupling
reaction
benzofuran
azadienes.
The
involvement
t-BuONa
is
essential
in
this
process.
Remarkably,
technique
boasts
mild
conditions
exceptional
compatibility
various
functional
groups,
rendering
it
versatile
invaluable
asset
the
realm
organic
synthesis.