Chemical Science,
Год журнала:
2019,
Номер
10(11), С. 3401 - 3407
Опубликована: Янв. 1, 2019
A
quinone-mediated
general
synthetic
platform
for
the
construction
of
primary
α-tertiary
amines
from
abundant
α-branched
amine
starting
materials
is
described.
This
procedure
pivots
on
efficient
in
situ
generation
reactive
ketimine
intermediates
and
subsequent
reaction
with
carbon-centered
nucleophiles
such
as
organomagnesium
organolithium
reagents,
TMSCN,
creating
quaternary
centers.
Furthermore,
extension
to
reverse
polarity
photoredox
catalysis
enables
reactivity
electrophiles,
via
a
nucleophilic
α-amino
radical
intermediate.
efficient,
broadly
applicable
scalable
amine-to-amine
was
successfully
applied
library
API
synthesis
functionalization
drug
molecules.
Journal of the American Chemical Society,
Год журнала:
2019,
Номер
141(36), С. 14062 - 14067
Опубликована: Сен. 3, 2019
The
functionalization
of
unactivated
C(sp3)-H
bonds
poses
a
significant
challenge
due
to
their
ubiquity
and
relative
similarity
in
most
organic
frameworks.
Herein,
we
describe
the
use
combined
photoredox
nickel
catalytic
system
for
regioselective
C(sp3)-C(sp3)
coupling
alkyl
bromides.
Positional
selectivity
is
dictated
by
1,5-hydrogen
atom
transfer
(HAT)
reaction
pendent
amide.
Interception
this
radical
Ni
catalyst
allows
distal
alkylation
occur
good
yield
excellent
selectivity.
Nature Communications,
Год журнала:
2020,
Номер
11(1)
Опубликована: Янв. 21, 2020
Abstract
Transition
metal
catalyzed
Sonogashira
cross-coupling
of
terminal
alkynes
with
aryl(vinyl)
(pseudo)halides
has
been
successfully
extended
to
alkyl
halides
for
the
synthesis
functionalized
internal
alkynes.
The
direct
alkynylation
remote
unfunctionalized
sp
3
carbon
by
remains
difficult
realize.
We
report
herein
an
approach
this
synthetic
challenge
developing
two
catalytic
protocols.
In
presence
a
amount
Cu(I)
salt
and
tridentate
ligand
(
t
Bu
-terpyridine),
O
-acyloximes
derived
from
cycloalkanones
acyclic
ketones
are
efficiently
coupled
afford
variety
γ-
δ-alkynyl
nitriles
γ-alkynyl
ketones,
respectively.
These
reactions
proceed
through
domino
sequence
involving
copper-catalyzed
reductive
generation
iminyl
radical
followed
translocation
via
either
β-scission
or
1,5-hydrogen
atom
transfer
(1,5-HAT)
resulting
translocated
radicals.
protocols
applicable
complex
natural
products.
Angewandte Chemie International Edition,
Год журнала:
2019,
Номер
58(26), С. 8912 - 8916
Опубликована: Апрель 18, 2019
The
dual
function
of
the
N-F
bond
as
an
effective
oxidant
and
subsequent
nitrogen
source
in
intramolecular
aliphatic
C-H
functionalization
reactions
is
explored.
Copper
catalysis
demonstrated
to
exercise
full
regio-
chemoselectivity
control,
which
opens
new
synthetic
avenues
nitrogenated
heterocycles
with
predictable
ring
sizes.
For
first
time,
a
uniform
manifold
has
been
identified
for
construction
both
pyrrolidine
piperidine
cores.
individual
steps
this
copper
oxidation
were
elucidated
by
control
experiments
computational
studies,
clarifying
singularity
characterizing
catalytic
cycle
be
based
on
copper(I/II)
manifold.
Chemical Science,
Год журнала:
2019,
Номер
10(11), С. 3401 - 3407
Опубликована: Янв. 1, 2019
A
quinone-mediated
general
synthetic
platform
for
the
construction
of
primary
α-tertiary
amines
from
abundant
α-branched
amine
starting
materials
is
described.
This
procedure
pivots
on
efficient
in
situ
generation
reactive
ketimine
intermediates
and
subsequent
reaction
with
carbon-centered
nucleophiles
such
as
organomagnesium
organolithium
reagents,
TMSCN,
creating
quaternary
centers.
Furthermore,
extension
to
reverse
polarity
photoredox
catalysis
enables
reactivity
electrophiles,
via
a
nucleophilic
α-amino
radical
intermediate.
efficient,
broadly
applicable
scalable
amine-to-amine
was
successfully
applied
library
API
synthesis
functionalization
drug
molecules.
