Organic Letters,
Год журнала:
2023,
Номер
25(43), С. 7810 - 7815
Опубликована: Окт. 26, 2023
A
rhodium-catalyzed
enantioselective
hydroboration/cyclization
reaction
of
1,6-enynes
is
achieved
by
employing
a
spirosiladiphosphine
ligand.
The
process
allows
the
synthesis
five-membered
hetero-
and
carbocycles
bearing
boron
handle
with
high
levels
activity
selectivity.
Various
enynes
organoboranes
(HBdan,
HBpin,
HBmp,
HBamm)
have
been
accommodated,
containing
terminal
alkynes
integrated
into
for
first
time.
yields
selectivities
transformation
highlight
synthetic
utility
these
novel
ligands.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(19), С. 7306 - 7313
Опубликована: Май 5, 2021
A
Co-catalyzed
highly
regio-
and
enantioselective
reductive
coupling
of
alkynes
aldehydes
has
been
developed
under
visible
light
photoredox
dual
catalysis.
variety
enantioenriched
allylic
alcohols
have
obtained
by
using
unsymmetrical
internal
commercially
available
catalyst,
chiral
ligand,
reagents.
It
is
noteworthy
that
this
approach
considerable
advantages,
such
as
excellent
(>95:5
for
>40
examples),
stereo-
(up
to
>95:5
E/Z),
enantioselectivity
(92-99%
ee,
>35
examples)
control,
mild
reaction
conditions,
broad
substrate
scope,
good
functional
group
compatibility,
making
it
a
great
improvement
alkyne-aldehyde
reactions.
Science China Chemistry,
Год журнала:
2022,
Номер
65(3), С. 441 - 461
Опубликована: Янв. 5, 2022
Abstract
Carbonylation,
one
of
the
most
powerful
approaches
to
preparation
carbonylated
compounds,
has
received
significant
attention
from
researchers
active
in
various
fields.
Indeed,
impressive
progress
been
made
on
this
subject
over
past
few
decades.
Among
types
carbonylation
reactions,
asymmetric
is
a
straightforward
methodology
for
constructing
chiral
compounds.
Although
rhodium-catalyzed
enantioselective
hydroformylations
have
discussed
several
elegant
reviews,
general
review
palladium-catalyzed
carbonylations
still
missing.
In
review,
we
summarize
and
discuss
recent
achievements
reactions.
Notably,
review’s
contents
are
categorized
by
reaction
type.
Accounts of Chemical Research,
Год журнала:
2021,
Номер
54(24), С. 4545 - 4564
Опубликована: Ноя. 30, 2021
One
of
the
major
challenges
facing
organic
synthesis
in
21st
century
is
utilization
abundantly
available
feedstock
chemicals
for
fine
chemical
synthesis.
Regio-
and
enantioselective
union
easily
accessible
1,3-dienes
other
feedstocks
like
ethylene,
alkyl
acrylates,
aldehydes
can
provide
valuable
building
blocks
adorned
with
latent
functionalities
further
synthetic
elaboration.
Through
an
approach
that
relies
on
mechanistic
insights
systematic
examination
ligand
counterion
effects,
we
developed
efficient
cobalt-based
catalytic
system
[(P∼P)CoX2/Me3Al]
(P∼P
=
bisphosphine)
to
effect
first
heterodimerization
several
types
ethylene.
In
addition
simple
cyclic
acyclic
dienes,
siloxy-1,3-dienes
participate
this
reaction,
giving
highly
functionalized,
nearly
enantiopure
silyl
enolates,
which
be
used
subsequent
C-C
C-X
bond-forming
reactions.
As
our
understanding
mechanism
reaction
improved,
attention
was
drawn
more
challenging
partners
acrylates
(one
largest
volume
feedstocks)
as
olefin
instead
Prompted
by
intrinsic
limitations
using
aluminum
alkyls
activators
explored
fundamental
chemistry
lesser
known
(P∼P)Co(I)X
species
discovered
presence
halide
sequestering
agents,
such
sodium
tetrakis[3,5-bis(trifluoromethyl)phenyl]borate
(NaBARF)
or
(C6F5)3B,
certain
chiral
bisphosphine
complexes
are
superb
catalysts
regio-
acrylates.
We
have
since
found
these
cationic
Co(I)
catalysts,
most
conveniently
prepared
situ
reduction
corresponding
cobalt(II)
zinc
NaBARF,
promote
[2
+
2]-cycloaddition
between
alkynes
astonishing
variety
alkenyl
derivatives
give
functionalized
cyclobutenes.
reactions
1,3-enynes
alkyne
ethylene
followed
a
1,4-addition
tandem
fashion
cyclobutanes
all-carbon
quaternary
center,
set
molecules
maps
well
into
many
medicinally
relevant
compounds.
another
application,
find
Co(I)-catalysts
selective
hydroacylation
1,2-hydroboration
prochiral
1,3-dienes.
Further,
Co(I)-catalyst
promotes
cycloisomerization
hydroalkenylation
1,6-enynes
produce
carbo-
heterocyclic
Surprisingly
regioselectivity
alkene
depends
whether
it
acrylate,
acrylate
produces
uncommon
Z-adduct.
This
Account
will
summary
enabling
basic
discoveries
attendant
developments
led
unique
Co(I)-complexes
disparate
C-B
It
hope
stimulate
work
versatile
derived
from
earth-abundant
metal.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(46)
Опубликована: Сен. 23, 2022
Abstract
The
introduction
of
fluorine‐containing
groups
into
organic
molecules
can
significantly
affect
their
physical
and
chemical
properties
has
long
been
used
as
an
effective
strategy
for
drug
discovery
development.
Consequently,
the
development
catalytic
asymmetric
methods
synthesis
heterocycles
is
highly
desirable
sought
after.
Herein,
we
describe
a
nickel‐catalyzed
defluorinative
cyclization
fluoroalkyl‐substituted
1,6‐enynes,
providing
expedient
access
to
synthetically
attractive
4‐fluorovinyl‐substituted
2‐pyrrolidones
in
good
yields
with
remarkable
high
levels
chemo‐,
regio‐,
enantioselectivities
(90–99
%
ee,>35
examples).
This
protocol
features
readily
available
starting
materials
excellent
functional
group
compatibility,
exhibits
complementary
regioselectivity.
utility
this
was
demonstrated
enantioselective
antiepileptic
Seletracetam.
Nature Communications,
Год журнала:
2023,
Номер
14(1)
Опубликована: Март 9, 2023
Transition-metal
catalyzed
asymmetric
cyclization
of
1,6-enynes
has
emerged
as
a
powerful
method
for
the
construction
carbocycles
and
heterocycles.
However,
very
rare
examples
worked
under
electrochemical
conditions.
We
report
herein
Co-catalyzed
enantioselective
intramolecular
reductive
coupling
enynes
via
electrochemistry
using
H2O
hydride
source.
The
products
were
obtained
in
good
yields
with
high
regio-
enantioselectivities.
It
represents
progress
on
cobalt-catalyzed
transformation
general
substrate
scope.
DFT
studies
explored
possible
reaction
pathways
revealed
that
oxidative
by
LCo(I)
is
more
favorable
than
addition
or
other
pathways.
Advanced Synthesis & Catalysis,
Год журнала:
2024,
Номер
366(6), С. 1220 - 1268
Опубликована: Янв. 22, 2024
Abstract
Elaborated
molecular
architectures,
specifically
those
bearing
one
or
more
carbon
stereocenters,
stand
as
an
important
class
of
carbocyclic
and
heterocyclic
frameworks
because
they
are
frequently
occurring
core
structures
in
numerous
natural
products
biologically
active
pharmaceutical
molecules.
Over
the
past
few
decades,
development
versatile
synthetic
approaches
via
cascade
cyclization
reactions
1,6‐enynes
for
construction
a
series
fused
spiro
compounds
has
been
focus
great
deal
research
initiatives.
These
synthesis
strategies
peculiarly
fascinating
context
assembly
wide
array
molecules,
products,
agrochemicals,
functional
materials.
In
this
review,
recent
developments
transformations
with
diverse
coupling
reagents
summarized
since
2018,
which
could
be
divided
into
five
categories:
1)
Introduction;
2)
Transition
metal
catalyzed
1,6‐enynes;
3)
Metal‐free
4)
Visible‐light‐induced
5)
Electrocatalytic
1,6‐enynes.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Апрель 4, 2024
Abstract
Carbo-
and
heterocycles
are
frequently
used
as
crucial
scaffolds
in
natural
products,
fine
chemicals,
biologically
pharmaceutically
active
compounds.
Transition-metal-catalyzed
cyclization
of
1,6-enynes
has
emerged
a
powerful
strategy
for
constructing
functionalized
carbo-
heterocycles.
Despite
significant
progress,
the
regioselectivity
alkyne
functionalization
is
entirely
substrate-dependent.
And
only
exo
-cyclization/cross-coupling
products
can
be
obtained,
while
endo
-selective
cyclization/cross-coupling
remains
elusive
still
poses
formidable
challenge.
In
this
study,
we
disclose
nickel-catalyzed
switchable
arylation/cyclization
which
nature
ligand
dictates
arylation,
electrophilic
trapping
reagents
determine
selectivity
mode.
Specifically,
using
commercially
available
1,10-phenanthroline
facilitates
trans
-arylation/cyclization
to
obtain
seven-membered
ring
2-naphthyl-substituted
bisbox
promotes
cis
access
six-membered
products.
Diastereoselective
cyclizations
have
also
been
developed
synthesis
enantioenriched
piperidines
azepanes,
core
structural
elements
pharmaceuticals
possessing
important
biological
activities.
Furthermore,
experimental
density
functional
theory
studies
reveal
that
arylation
process
controlled
by
steric
hindrance
ligand;
reaction
mechanism
involves
-cyclization
followed
Dowd-Beckwith-type
expansion
form
Journal of the American Chemical Society,
Год журнала:
2020,
Номер
143(1), С. 53 - 59
Опубликована: Дек. 24, 2020
Spirocycles
play
an
important
role
in
drug
discovery
and
development
owing
to
their
inherent
three-dimensionality
structural
novelty.
Despite
the
recent
significant
progress,
straightforward
catalytic
asymmetric
assembly
of
spirocyclic
scaffolds
with
multiple
stereocenters
from
readily
available
starting
materials
remains
a
formidable
challenge.
Herein,
we
develop
unprecedented
nickel-catalyzed
one-pot
synthesis
enantioenriched
spiroindanones
easily
1,6-enynes
o-formylarylboronic
acids.
The
reaction
proceeds
smoothly
under
redox-neutral
conditions,
without
need
for
additional
hydrogen
donor,
features
broad
substrate
scope
excellent
regio-,
enantio-,
diastereoselectivity.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(32), С. 12825 - 12835
Опубликована: Авг. 5, 2021
Ketones
are
among
the
most
widely
used
intermediates
in
organic
synthesis,
and
their
synthesis
from
inexpensive
feedstocks
could
be
quite
impactful.
Regio-
enantioselective
hydroacylation
reactions
of
dienes
provide
facile
entry
into
useful
ketone-bearing
chiral
motifs
with
an
additional
latent
functionality
(alkene)
suitable
for
further
elaboration.
Three
classes
dienes,
2-
or
4-monosubstituted
2,4-disubstituted
1,3-dienes,
undergo
cobalt(I)-catalyzed
regio-
hydroacylation,
giving
products
high
enantiomeric
ratios
(er).
These
highly
dependent
on
ligands,
we
have
identified
ligands
reaction
conditions
each
class
dienes.
2-Substituted
predominantly
1,2-addition,
whereas
4-substituted
terminal
give
4,1-
4,3-hydroacylation
depending
aldehyde,
aliphatic
aldehydes
4,1-addition
aromatic
4,3-addition.
Included
substrates
feedstock
isoprene
(US$1.4/kg)
myrcene
(US$129/kg),
several
common
aldehydes.
We
propose
oxidative
dimerization
mechanism
that
involves
a
Co(I)/Co(III)
redox
cycle
appears
to
initiated
by
cationic
Co(I)
intermediate.
Studies
using
isolated
neutral
complexes
confirm
critical
role
these
reactions.
Enantioselective
1,2-hydroacylation
2-trimethylsiloxy-1,3-diene
reveals
hitherto
undisclosed
route
siloxy-protected
aldols.
Finally,
syntheses
anti-inflammatory
drug
(S)-Flobufen
(2
steps,
92%
yield,
>99:1
er)
food
additive
(S)-Dihydrotagetone
(1
step,
83%
yield;
96:4
illustrate
power
this
method
preparation
commercially
relevant
compounds.