Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(17), С. 3547 - 3551
Опубликована: Янв. 1, 2023
A
highly
efficient
Rh(II)
catalyzed
non-radical
protocol
to
access
NH-free
C-3
bifunctional
oxindoles,
which
possess
3-allyl
and
3-amino
simultaneously,
was
first
achieved
by
employing
an
intermolecular
[2,3]-sigmatropic
rearrangement
reaction
between
diazooxindoles
tertiary
allylic
amines.
Utilizing
readily
available
allylamines
as
the
nitrogen
allyl
source
concurrently,
a
wide
range
of
bio-active
3-allyl-3-(amino)oxindoles
were
obtained
in
excellent
yields
under
very
mild
conditions;
meanwhile,
TON
can
be
up
90
000.
Our
study
addresses
gap
literature
investigating
rearrangements
ammonium
ylides
with
diazoamides,
have
been
relatively
understudied.
Chemical Communications,
Год журнала:
2021,
Номер
57(94), С. 12607 - 12610
Опубликована: Янв. 1, 2021
A
gold
catalyzed
formal
intermolecular
[2+3]
cyclo-coupling
of
1,3-enynes
with
phenols
was
developed
to
prepare
dihydrobenzofuran
derivatives
the
addition
2,6-dichloropyridine
N-oxide,
in
which,
a
highly
ortho-selective
phenol
SEAr
functionalization
achieved
by
using
as
α-oxo
vinyl
carbenoid
surrogates.
Synthesis,
Год журнала:
2021,
Номер
53(20), С. 3639 - 3652
Опубликована: Июль 14, 2021
Abstract
This
review
summarizes
approaches
and
caveats
in
computational
modeling
of
transition-metal-catalyzed
sigmatropic
rearrangements
involving
carbene
transfer.
We
highlight
contemporary
examples
combined
synthetic
theoretical
investigations
that
showcase
the
synergy
achievable
by
integrating
experiment
theory.
1
Introduction
2
Mechanistic
Models
3
Theoretical
Approaches
Caveats
3.1
Recommended
Computational
Tools
3.2
Choice
Functional
Basis
Set
3.3
Conformations
Ligand-Binding
Modes
3.4
Solvation
4
Synergy
Experiment
Theory
–
Case
Studies
4.1
Metal-Bound
or
Free
Ylides?
4.2
Paddlewheel
Complexes
4.3
No
Metal,
Just
Light
4.4
How
To
‘Cope’
with
Nonstatistical
Dynamic
Effects
5
Outlook
Organic Letters,
Год журнала:
2024,
Номер
26(43), С. 9191 - 9197
Опубликована: Окт. 23, 2024
The
novel
reactivity
of
a
less
selective
and
more
reactive
acceptor-acceptor
kind
diazo
pyrazolone
(DIPOL)
has
been
explored
under
visible
light
for
the
first
time.
We
have
successfully
demonstrated
reaction
DIPOL
different
allyl
thioethers
blue
to
construct
wide
variety
products
including
pesticidal
analogue
exclusively
in
excellent
chemoselectivity
good
yields.
Moreover,
possible
side
emanating
from
ketene
were
not
observed.
This
protocol
works
smoothly
an
environmentally
benign
solvent
inert
free
conditions.
practicality
extended
photoflow
reaction,
also,
direct
exposure
sunlight.
Chemistry - An Asian Journal,
Год журнала:
2024,
Номер
unknown
Опубликована: Окт. 23, 2024
A
new
approach
for
the
synthetically
important
γ-functionalized
enals
has
been
developed.
The
strategy
involves
rhodium-catalyzed
direct
C-C
&
C-S
bond
forming
site-selective
γ-difunctionalization
of
diazoenals
with
aryl
propargyl
sulfides
via
sulfur
ylide
[2,3]
sigmatropic
rearrangement,
resulting
in
highly
functionalized
γ-allenyl(sulfanyl)enals
excellent
yield
at
ambient
temperature.
This
versatile
constitutes
a
viable
alternative
to
remote
carbonyl-directed
γ-functionalization
unmodified
which
suffer
from
competitive
side
reactions.
synthetic
utility
was
demonstrated
by
InCl
The Journal of Physical Chemistry A,
Год журнала:
2022,
Номер
126(45), С. 8372 - 8379
Опубликована: Ноя. 6, 2022
In
this
work,
we
studied
the
wavelength
(520
or
350
nm)
dependence
of
photochemical
decomposition
1-phenyl-1-diazopropane
(PDP)
and
1-phenyl-1-propyl
diazirine
(PED)
by
means
high-level
ab
initio
quantum
chemical
calculations
(CASSCF
MS-CASPT2)
to
obtain
qualitative
quantitative
results.
It
is
found
that
photochemistry
PDP
governed
nonradiative
deactivation
processes
can
involve
one
two
S1/S0
conical
intersections
(CI1
CI2)
depending
on
radiation;
CI2
only
accessible
at
shortest
wavelength.
demonstrated
main
intermediate
titled
compounds
1-ethyl-1-phenyl
carbene
(EPC).
Upon
irradiation
with
520
nm
light,
always
generated
in
its
ground
state
as
closed-shell
singlet
carbene.
contrast,
radiation
directly
decompose
into
S1
(open
shell)
N2
when
intersection
avoided.
Once
formed
state,
it
experience
excited
intramolecular
proton
transfer
along
a
seam
crossing
(ESIPT-SC)
S0
states
yield
alkene
derivative;
is,
reaction
takes
places
degenerate
potential
energy
surface
where
electronic
have
equal
energy.
addition,
EPC
absorbs
(double
excitations);
therefore,
there
another
possible
route
induce
well
slightly
different
changing
because
(when
intense
enough)
decreases
amount
available
generates
highly
vibrationally
carbene;
after
excitation,
deactivate
via
emission
decay
through
cascade
first
(S1),
ESIPT-SC
operative
again.
Density
functional
theory
calculations
were
applied
to
study
four
previously
published
metal-catalyzed
[2,3]-rearrangements
from
onium
ylide
intermediates,
in
pursuit
of
generalizations
about
when,
during
these
types
reactions,
catalysts
dissociate.
Our
results
corroborate
past
studies
where
free
mechanisms
proposed
be
operative.
Calculations
on
case
predict
that
the
origin
metal-catalyst
‘falling
off’
(dissociation)
can
attributed
primarily
steric
bulkiness
groups
adjacent
carbene
carbon.
