Enantioselective Synthesis of Allylic Sulfones via Rhodium-Catalyzed Direct Hydrosulfonylation of Allenes and Alkynes
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(25), С. 16996 - 17002
Опубликована: Июнь 14, 2024
A
highly
regio-
and
enantioselective
hydrosulfonylation
using
commercially
available
sodium
sulfinates
is
reported,
providing
the
first
direct
asymmetric
rhodium-catalyzed
of
allenes/alkynes
to
synthesize
chiral
allylic
sulfones.
Ligand
screening
studies
demonstrated
indispensable
role
C1-symmetric
P,N-ligand
(Rax,S,S)-StackPhim
for
achieving
both
high
regioselecitivity
(>20:1)
enantioselectivity
(up
97%
ee).
Notably,
operationally
simple
method
mild
conditions
allow
rapid
preparation
sulfones
with
a
wide
scope
functional
groups.
Moreover,
use
tert-butyldimethylsilyloxymethanesulfinate
enables
collective
synthesis
various
sulfone
derivatives
after
transformations
protected
hydroxymethyl
product.
Язык: Английский
Catalytic Enantioselective Friedel-Crafts Allenylic Alkylation
Опубликована: Ноя. 9, 2023
The
first
catalytic
enantioselective
Friedel-Crafts
(FC)
allenylic
alkylation
for
the
creation
of
central
chirality
has
been
developed
under
cooperative
Ir(I)/(phosphoramidite,olefin)
and
Lewis
acid
catalysis.
Using
racemic
alcohol
as
electrophile,
this
enantioconvergent
reaction
proceeds
through
an
Ir(I)-stabilized
carbocation
intermediate,
which
is
intercepted
with
a
variety
electron-rich
arenes
heteroarenes.
resulting
highly
enantioenriched
(up
to
>99.5:0.5
er)
1,1-disubstituted
methanes,
bearing
benzylic
carbon
stereocenter,
are
obtained
complete
regiocontrol
–
both
on
(hetero)arenes
well
fragment.
This
protocol
allows
formal
introduction
4
alkane
chains
into
stereocenter.
An
intramolecular
version
FC
also
shown
proceed
promising
enantioselectivity
same
conditions.
Язык: Английский
Rhodium‐Catalyzed Enantioselective Intramolecular Hydroalkoxylation of Allenes and Application in the Total Synthesis of (R,R,R)‐α‐Tocopherol
Chemistry - A European Journal,
Год журнала:
2024,
Номер
30(46)
Опубликована: Июнь 10, 2024
We
report
herein
of
a
novel,
enantioselective
and
rhodium-
catalyzed
cyclisation
allenyl
alcohols
towards
chiral
α-vinylic,
cyclic
ethers
employing
rhodium/(R,R)-Me-ferrocelane
catalyst.
The
corresponding
products
were
obtained
in
general
high
yields
enantioselectivities.
synthetic
value
our
was
further
exemplified
by
transformations
the
allylic
ether
function.
Furthermore,
applying
newly
developed
method
previously
reported
route
total
synthesis
(R,R,R)-α-tocopherol,
we
accomplished
significantly
improved
2
Язык: Английский
Catalytic Enantioselective Friedel‐Crafts Allenylation
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(47)
Опубликована: Авг. 7, 2024
Abstract
The
first
enantioselective
Friedel‐Crafts
(FC)
allenylation
reaction
for
the
creation
of
central
chirality
is
developed
under
cooperative
Ir(I)/(phosphoramidite,olefin)
and
Lewis
acid
catalysis.
This
enantioconvergent
utilizes
racemic
allenylic
alcohol
as
electrophile
shows
compatibility
with
a
variety
electron‐rich
arenes
heteroarenes.
resulting
highly
enantioenriched
(up
to
>99.5
:
0.5
e.r.)
1,1‐disubstituted
methanes,
bearing
benzylic
carbon
stereocenter,
are
obtained
complete
regiocontrol
–
both
on
(hetero)arenes
well
fragment.
protocol
allows
formal
introduction
4‐carbon
alkyl
chain
into
(hetero)arenes,
along
stereocenter.
Judicious
synthetic
elaborations
not
only
lead
FC
alkylation
products
less
but
also
substituted
in
ortho
‐
even
meta
‐selective
fashion.
An
intramolecular
version
this
shown
proceed
promising
enantioselectivity
same
catalytic
conditions.
Mechanistic
studies
revealed
involvement
dynamic
kinetic
asymmetric
transformation
(DyKAT)
alcohols
reaction.
Язык: Английский
Catalytic Enantioselective Friedel‐Crafts Allenylation
Angewandte Chemie,
Год журнала:
2024,
Номер
136(47)
Опубликована: Авг. 7, 2024
Abstract
The
first
enantioselective
Friedel‐Crafts
(FC)
allenylation
reaction
for
the
creation
of
central
chirality
is
developed
under
cooperative
Ir(I)/(phosphoramidite,olefin)
and
Lewis
acid
catalysis.
This
enantioconvergent
utilizes
racemic
allenylic
alcohol
as
electrophile
shows
compatibility
with
a
variety
electron‐rich
arenes
heteroarenes.
resulting
highly
enantioenriched
(up
to
>99.5
:
0.5
e.r.)
1,1‐disubstituted
methanes,
bearing
benzylic
carbon
stereocenter,
are
obtained
complete
regiocontrol
–
both
on
(hetero)arenes
well
fragment.
protocol
allows
formal
introduction
4‐carbon
alkyl
chain
into
(hetero)arenes,
along
stereocenter.
Judicious
synthetic
elaborations
not
only
lead
FC
alkylation
products
less
but
also
substituted
in
ortho
‐
even
meta
‐selective
fashion.
An
intramolecular
version
this
shown
proceed
promising
enantioselectivity
same
catalytic
conditions.
Mechanistic
studies
revealed
involvement
dynamic
kinetic
asymmetric
transformation
(DyKAT)
alcohols
reaction.
Язык: Английский
Hydrooxygenation of C–C π-Bonds
Elsevier eBooks,
Год журнала:
2024,
Номер
unknown
Опубликована: Янв. 1, 2024
Язык: Английский
Selective Catalysts for the Homogeneous Semi‐Hydrogenation
Advanced Synthesis & Catalysis,
Год журнала:
2023,
Номер
365(24), С. 4538 - 4543
Опубликована: Сен. 5, 2023
Abstract
An
efficient
and
highly
selective
semi‐hydrogenation
of
terminal
alkynes
to
alkenes
using
neutral
dimeric
rhodium(I)
complexes
the
type
[Rh(
μ
‐Cl)(PP)]
2
is
presented.
Dehydroisophytol
(DIP)
was
chosen
as
alkyne
for
this
study
because
its
high
importance
in
industrial
production
synthetic
vitamin
E.
Excellent
selectivity
over
91%
towards
alkene
achieved
with
known
new
rhodium
catalysts.
No
deactivation
observed
molar
Rh:DIP
ratio
could
be
increased
1:20
000,
importantly,
no
reduction
observed.
The
results
presented
open
door
application
homogeneous
alkynes.
Язык: Английский