Highly Regio-selective Hydration of Ynamides under Catalyst-Free Conditions
Organic & Biomolecular Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
The
highly
regio-selective
hydration
of
ynamides
under
catalyst-free
conditions
has
been
demonstrated
for
easily
accessing
α-amidoketones
in
51-99%
yields.
excellent
regio-selectivity
is
believed
to
be
controlled
by
the
amide
group,
which
just
opposite
that
observed
Brønsted
acid-mediated
ynamides.
This
approach
convenient,
easy
operate,
and
exhibits
good
functionality
tolerance.
Язык: Английский
Nickel-Catalyzed Cross-Coupling Reaction of Aryl Bromides/Nitriles with Imidazolium Salts Involving Inert C–N Bond Cleavage
Organic Letters,
Год журнала:
2024,
Номер
26(21), С. 4520 - 4525
Опубликована: Май 16, 2024
We
herein
present
a
nickel-catalyzed
cross-coupling
reaction
of
aryl
halides
and
nitriles
with
imidazolium
salts.
A
series
2-arylated
imidazoles
could
be
obtained
in
moderate
to
good
yields
through
inert
C-N
bond
cleavage.
The
salt
this
acts
as
both
coupling
partner
Язык: Английский
Mechanisms and Stereoselectivities in the NHC-Catalyzed [4 + 2] Annulation of 2-Bromoenal and 6-Methyluracil-5-carbaldehyde
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(18), С. 12997 - 13008
Опубликована: Авг. 29, 2023
To
disclose
the
reaction
mechanism
and
selectivity
in
NHC-catalyzed
of
2-bromoenal
6-methyluracil-5-carbaldehyde,
a
systematic
computational
study
has
been
performed.
According
to
DFT
computations,
catalytic
cycle
is
divided
into
eight
elementary
steps:
nucleophilic
attack
NHC
on
2-bromoenal,
1,2-proton
transfer,
C–Br
bond
dissociation,
1,3-proton
addition
[2
+
2]
cycloaddition,
decarboxylation.
The
Bronsted
acid
DABCO·H+
plays
crucial
role
proton
transfer
decarboxylation
steps.
6-methyluracil-5-carbaldehyde
determines
both
chemoselectivity
stereoselectivity,
leading
R-configured
carbocycle-fused
uracil,
agreement
with
experimental
results.
NCI
analysis
indicates
that
CH···N,
CH···π,
LP···π
interactions
should
be
key
factor
for
determining
stereoselectivity.
ELF
shows
main
promoting
dissociation.
mechanistic
insights
obtained
present
work
may
guide
rational
design
potential
catalysts.
Язык: Английский
Theoretical study of [3 + 3] annulation reaction of bromoenal with β-tetralone catalysed by N-heterocyclic carbene
Molecular Physics,
Год журнала:
2024,
Номер
unknown
Опубликована: Июнь 3, 2024
N-heterocyclic
carbenes
(NHCs)
are
effective
organocatalysts,
which
widely
used
in
various
cycloaddition
reactions.
Among
them,
the
[3
+
3]
reaction
type
can
be
for
synthesis
of
six-membered
ring,
is
also
one
most
important
methods
formation
carbon–carbon
bonds
organic
chemistry.
In
this
paper,
a
possible
pathway
stereoselective
bromoenal
and
β-tetralone
have
been
investigated
at
M06-2X/6–31G(d,p)/IEFPCM(THF)
level.
Our
suggested
mechanism
includes
binding
NHC
to
bromoenal,
1,2-proton
transfer,
debromination,
1,3-proton
shift,
Michael
addition,
protonation,
deprotonation
cyclisation,
regeneration.
The
stereochemistry
determined
by
addition
step,
favourable
generates
R-configurational
dihydropyranone.
Furthermore,
through
use
global
reactivity
indexes
(GRIs),
we
able
demonstrate
that
nucleophilicity
increased
NHC.
mechanistic
insights
gained
work
should
helpful
rational
design
potential
catalysts
analogous
Язык: Английский