The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(6), С. 4244 - 4248
Опубликована: Фев. 23, 2024
Herein,
we
report
a
synthetic
method
to
access
range
of
highly
substituted
indoles
via
the
B(C6F5)3-catalyzed
transfer
2°
alkyl
groups
from
amines.
The
transition-metal-free
catalytic
approach
has
been
demonstrated
across
broad
and
amine
donors,
including
various
substituents
on
both
reacting
components,
useful
C(3)-alkylated
indole
products.
process
can
be
performed
using
Schlenk
line
techniques
in
combination
with
commercially
available
B(C6F5)3·nH2O
solvents,
which
obviates
requirement
for
specialized
equipment
(e.g.,
glovebox).
Chemical Reviews,
Год журнала:
2019,
Номер
119(14), С. 8231 - 8261
Опубликована: Янв. 14, 2019
The
study
of
main-group
molecules
that
behave
and
react
similarly
to
transition-metal
(TM)
complexes
has
attracted
significant
interest
in
recent
decades.
Most
notably,
the
attractive
idea
replacing
all-too-often
rare
costly
metals
from
catalysis
motivated
efforts
develop
main-group-element-mediated
reactions.
Main-group
elements,
however,
lack
electronic
flexibility
TM
arises
combinations
empty
filled
d
orbitals
seem
ideally
suited
bind
activate
many
substrates.
In
this
review,
we
look
at
boron,
an
element
despite
its
nonmetal
nature,
low
atomic
weight,
relative
redox
staticity
achieved
great
milestones
terms
TM-like
reactivity.
We
show
how
interelement
cooperative
systems,
diboron
molecules,
hypovalent
fifth
can
acquire
a
truly
metallomimetic
character.
As
discuss,
character
is
powerfully
demonstrated
by
reactivity
boron-based
with
H2,
CO,
alkynes,
alkenes
even
N2.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(48), С. 20002 - 20014
Опубликована: Ноя. 17, 2021
The
articulation
of
the
notion
"frustrated
Lewis
pairs"
(FLPs)
emerged
from
discovery
that
H2
can
be
reversibly
activated
by
combinations
sterically
encumbered
main
group
acids
and
bases.
This
has
prompted
numerous
studies
focused
on
various
perturbations
acid/base
applications
to
organic
reductions.
Perspective
focuses
new
directions
developments
are
emerging
this
FLP
chemistry
involving
hydrogen.
Three
areas
discussed
including
approaches
reductions,
reductions
small
molecules,
advances
in
heterogeneous
systems.
These
foci
serve
illustrate
despite
having
its
roots
chemistry,
simple
concept
FLPs
is
being
applied
across
discipline.
ACS Catalysis,
Год журнала:
2019,
Номер
9(9), С. 8575 - 8580
Опубликована: Авг. 21, 2019
Herein
we
report
the
iron-catalyzed
β-C(sp3)-methylation
of
primary
alcohols
using
methanol
as
a
C1
building
block.
This
borrowing
hydrogen
approach
employs
well-defined
bench-stable
(cyclopentadienone)iron(0)
carbonyl
complex
precatalyst
(5
mol
%)
and
enables
diverse
selection
substituted
2-arylethanols
to
undergo
in
good
isolated
yields
(24
examples,
65%
average
yield).
Angewandte Chemie International Edition,
Год журнала:
2019,
Номер
58(13), С. 4248 - 4253
Опубликована: Янв. 23, 2019
Abstract
The
alkene
transfer
hydrogenation
(TH)
of
a
variety
alkenes
has
been
achieved
with
simple
AeN′′
2
catalysts
[Ae=Ca,
Sr,
Ba;
N′′=N(SiMe
3
)
]
using
1,4‐cyclohexadiene
(1,4‐CHD)
as
H
source.
Reaction
1,4‐CHD
gave
benzene,
N′′H,
and
the
metal
hydride
species
N′′AeH
(or
aggregates
thereof),
which
is
catalyst
for
hydrogenation.
BaN′′
by
far
most
active
catalyst.
Hydrogenation
activated
C=C
bonds
(e.g.
styrene)
proceeded
at
room
temperature
without
polymer
formation.
Unactivated
(isolated)
1‐hexene)
needed
higher
(120
°C)
but
double‐bond
isomerization.
ligands
fully
control
course
catalytic
reaction,
can
be:
1)
TH,
2)
dehydrogenation,
or
3)
polymerization.
DFT
calculations
support
formation
deprotonation
followed
transfer.
Convenient
access
to
larger
quantities
,
its
high
activity
selectivity,
many
advantages
TH
make
this
attractive
procedure
ACS Catalysis,
Год журнала:
2020,
Номер
10(8), С. 4835 - 4840
Опубликована: Апрель 9, 2020
The
direct
C3
alkylation
of
indoles
and
oxindoles
is
a
challenging
transformation,
only
few
methods
exist.
Utilizing
the
underexplored
ability
triaryl
boranes
to
mediate
heterolytic
cleavage
α-nitrogen
C-H
bonds
in
amines,
we
have
developed
catalytic
approach
for
wide
range
using
amine-based
alkylating
agents.
We
also
employed
this
borane-catalyzed
strategy
an
alkylation-ring
opening
cascade.
Chemical Communications,
Год журнала:
2018,
Номер
55(9), С. 1217 - 1220
Опубликована: Дек. 21, 2018
A
transition
metal-free
intermolecular
redox-neutral
β-alkylation
of
acyclic
tertiary
amines
via
borrowing
hydrogen
catalyzed
by
commercially
available
B(C6F5)3
was
achieved.
