3-Alkyl-1,2,4-triazines as Heterocyclic Platforms for Organocatalytic Enantioselective Benzylic C–H Functionalization
Organic Letters,
Год журнала:
2025,
Номер
27(6), С. 1504 - 1510
Опубликована: Янв. 31, 2025
The
α-3-(1,2,4-triazine)-α-cyanoacetate
derivatives
exhibit
a
unique
and
well-defined
dearomatized
structure
undergoing
efficient
organocatalytic
aromatization–alkylation
sequences
with
Michael
acceptors
in
order
to
construct
an
all-carbon
tetrasubstituted
stereocenter
high
ee
values.
These
new
players
the
field
of
enantioselective
catalytic
benzylic
C–H
functionalization
afford
versatile
molecular
platforms
toward
construction
valuable
3D-heterocycles.
Язык: Английский
Catalytic Fluorination of α-Branched Ketones with Nucleophilic Fluorine
Organic Letters,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 24, 2025
We
herein
disclose
the
first
example
of
metal-free,
redox-umpolung-enabled
catalytic
fluorination
α-branched
ketones
with
nucleophilic
fluorine
by
judicious
choice
an
oxidant.
The
strategic
use
cyclopropyl
malonoyl
peroxide
in
hypervalent
iodine(III)
catalysis
expands
modularity
and
generality
construction
α-fluorinated
ideally
orthogonal
reactivity
space,
avoiding
competing
oxidation
processes.
Characteristic
for
this
transformation
is
its
operational
simplicity,
mild
reaction
conditions,
gram-scale
synthetic
ability.
Язык: Английский
Asymmetric Cobalt Catalysis for the Construction of Quaternary Stereogenic Centers with Fluorine Atoms
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 17, 2025
The
advancement
of
robust
synthetic
methodologies
for
generating
fluorinated
quaternary
carbon
chiral
centers
is
highly
sought
after
in
the
fields
organic
and
medicinal
chemistry.
This
study
successfully
provides
such
compounds
through
cobalt-catalyzed
asymmetric
Negishi
coupling
reactions
α-bromo-α-fluoro
ketones
with
aryl/alkenyl
zinc
reagents.
adjustment
unsymmetric
N,N,N-tridentate
(CUT)
ligands
played
a
key
role
improving
reactivity
selectivity
cobalt
catalysis,
preventing
formation
hydrodebromination
byproducts,
accommodating
sterically
hindered
substrates
heterocycles.
Control
kinetic
experiments
reveal
that
transmetalation
serves
as
rate-limiting
step,
mechanistic
characteristic
sets
newly
developed
cross-couplings
apart
from
previous
methodologies.
Язык: Английский
Copper-Catalyzed Asymmetric Tertiary Radical Cyanation for the Synthesis of Chiral Tetrasubstituted Monofluoroacyl Nitriles
Organic Letters,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 10, 2024
The
construction
of
chiral
tetrasubstituted
α-fluoro-α-cyano
carbonyl
compounds
remains
a
key
challenge
in
synthetic
organic
chemistry
because
their
popularity
multiple
disciplines.
In
this
paper,
we
report
the
copper-catalyzed
asymmetric
fluorinated
tertiary
radical
cyanation
reaction
cyclic
α-iodo-α-fluoroindanones
with
TMSCN
to
achieve
nitriles
carbon–fluorine
quaternary
stereogenic
centers.
Thus,
an
array
optically
active
monofluoroacyl
were
synthesized
high
efficiency
and
excellent
enantioselectivities
(up
91%
yield,
99%
ee).
Moreover,
mechanistic
investigations,
including
experiments,
conducted
clarify
pathway
stereochemical
outcomes.
Язык: Английский
Base‐Promoted Diastereoselective Addition of 2‐Aryloxy‐2‐Fluoroketones to N‐(tert‐Butylsulfinyl)Imines
ChemistrySelect,
Год журнала:
2024,
Номер
9(46)
Опубликована: Дек. 1, 2024
Abstract
The
asymmetric
construction
of
a
quaternary
fluorine‐containing
stereogenic
carboncenter
is
highly
valuable
for
the
development
fluoroine‐containing
bioactive
molecules.
Herein,
base‐promoted,
diastereoselective
Mannich‐type
reaction
2‐aryloxy‐2‐fluoroketones
with
N
‐(
tert
‐butylsulfinyl)imines
has
been
developed.
A
number
addition
products
featuring
fluorinated
stereocarbon
centre
and
β‐fluoroamine
structural
motif
have
readily
obtained
in
good
yields
moderate
to
diastereoselectivities.
absolute
configuration
major
diasteromer
was
determined
by
X‐ray
crystallography
analysis,
closed
transition‐state
mode
proposed
explain
stereochemical
outcome
this
reaction.
In
addition,
product
efficiently
converted
into
α‑fluoro‐β‐amino
alcohol
through
desulfinylation
followed
reduction
carbonyl
group.
Язык: Английский