Angewandte Chemie,
Journal Year:
2023,
Volume and Issue:
135(45)
Published: Oct. 2, 2023
Abstract
Light
olefins
are
abundantly
manufactured
in
the
petroleum
industry
and
thus
represent
ideal
starting
materials
for
modern
chemical
synthesis.
Selective
divergent
transformations
of
feedstock
light
to
value‐added
chemicals
highly
sought‐after
but
remain
challenging.
Herein
we
report
an
exceptionally
regioselective
carbonickelation
alkenes
followed
by
situ
trapping
with
three
types
nucleophiles,
namely
a
reductant,
base,
or
Grignard
reagent.
This
protocol
enables
efficient
1,2‐hydrofunctionalization,
dicarbofunctionalization,
branched‐selective
Heck‐type
cross‐coupling
aryl
alkenyl
reagents
streamline
access
diverse
alkyl
arenes
complex
alkenes.
Harnessing
bulky
N
‐heterocyclic
carbene
ligands
acenaphthyl
backbones
nickel
catalysts
is
crucial
attain
high
reactivity
selectivity.
strategy
provides
rare,
modular,
platform
upgrading
expected
find
broad
applications
medicinal
chemistry
industrial
processes.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(16), P. 3355 - 3360
Published: April 11, 2024
A
two-step
protocol
for
the
conversion
of
alkyl-substituted
alkynes
to
1,3-enynes
is
reported.
In
this
α-methenylation
process,
an
iron-catalyzed
propargylic
C–H
functionalization
delivers
tetramethylpiperidine-derived
homopropargylic
amines
which
undergo
facile
Cope
elimination
upon
N-oxidation
afford
enyne
products.
range
aryl
alkyl
and
dialkyl
acetylenes
were
found
be
suitable
substrates
constitutes
alkyne
analogue
Eschenmoser
methenylation
carbonyl
derivatives.
addition,
a
new
bench-stable
precatalyst
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(32), P. 22122 - 22128
Published: Aug. 5, 2024
The
discovery
and
utilization
of
main-group
element
catalysts
that
behave
similarly
to
transition
metal
(TM)
complexes
have
become
increasingly
active
areas
investigation
in
recent
years.
Here,
we
report
a
series
Lewis
acidic
bismuth(III)
allow
for
the
catalytic
allylic
C(sp3)–H
functionalization
olefins
via
an
organometallic
complexation-assisted
deprotonation
mechanism
generate
products
containing
new
C–C
bonds.
This
heretofore
unexplored
mode
reactivity
was
applied
regioselective
1,4-dienes
allylbenzene
substrates.
Experimental
computational
mechanistic
studies
support
key
steps
proposed
cycle,
including
intermediacy
elusive
Bi–olefin
allylbismuth
species.
Chemistry - A European Journal,
Journal Year:
2023,
Volume and Issue:
29(45)
Published: May 19, 2023
Cyclopentadienyliron
dicarbonyl-based
complexes
present
opportunities
for
underexplored
disconnections
in
synthesis.
Access
to
challenging
dihydropyrrolone
products
is
achieved
by
propargylic
C-H
functionalization
of
alkynes
the
formation
cyclic
organoiron
species.
Excellent
regioselectivity
unsymmetrical
observed
many
cases.
Notably,
under
these
stoichiometric
conditions
diverges
from
those
previously
catalysis,
occurring
at
more-substituted
terminus
alkyne,
allowing
methine
and
quaternary
centers.
Divergent
demetallation
intermediate
gives
access
chemically
diverse
which
are
amenable
further
functionalization.
Organic Process Research & Development,
Journal Year:
2023,
Volume and Issue:
27(11), P. 1913 - 1930
Published: Sept. 13, 2023
As
the
field
of
nonprecious
metal
catalysis
continues
to
expand,
we
pursue
a
review
series
covering
selected
transformations
in
this
area
over
short
time
interval
highlight
advancements.
We
seek
raise
awareness
both
current
art
and
need
continue
development
toward
broader
application
or
earth-abundant
metals
chemical
pharmaceutical
industries.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(45)
Published: Oct. 2, 2023
Light
olefins
are
abundantly
manufactured
in
the
petroleum
industry
and
thus
represent
ideal
starting
materials
for
modern
chemical
synthesis.
Selective
divergent
transformations
of
feedstock
light
to
value-added
chemicals
highly
sought-after
but
remain
challenging.
Herein
we
report
an
exceptionally
regioselective
carbonickelation
alkenes
followed
by
situ
trapping
with
three
types
nucleophiles,
namely
a
reductant,
base,
or
Grignard
reagent.
This
protocol
enables
efficient
1,2-hydrofunctionalization,
dicarbofunctionalization,
branched-selective
Heck-type
cross-coupling
aryl
alkenyl
reagents
streamline
access
diverse
alkyl
arenes
complex
alkenes.
Harnessing
bulky
N-heterocyclic
carbene
ligands
acenaphthyl
backbones
nickel
catalysts
is
crucial
attain
high
reactivity
selectivity.
strategy
provides
rare,
modular,
platform
upgrading
expected
find
broad
applications
medicinal
chemistry
industrial
processes.
Organometallics,
Journal Year:
2024,
Volume and Issue:
43(4), P. 449 - 456
Published: Feb. 15, 2024
Density
functional
theory
studies
for
the
role
of
N,N,N′,N′-tetramethylethylenediamine
(TMEDA)
in
iron-catalyzed
cross-coupling
reactions
between
phenylmagnesium
bromide
and
bromocycloheptane
have
been
investigated
using
B3LYP-D3BJ
functionals
SMD
(tetrahydrofuran)
model.
The
results
reveal
that
whole
catalytic
cycle
has
two
possible
pathways:
one
which
main
product
P1,
named
Path
A,
is
obtained
or
another
byproduct
P2,
B,
obtained.
TMEDA-bound
iron
intermediates
are
responsible
products
P1
P2.
radical
intermediate
initiated
by
TMEDA–iron
species
starts
reaction,
just
highlights
central
TMEDA
cycle.
Different
spin
states
checked.
calculated
helpful
understanding
mechanisms
involved
reactions.
It
shows
rate-determining
step
to
obtain
A
a
reductive
elimination
where
Gibbs
free
energy
solvent
THF,
ΔGsol,
9.5
kcal/mol,
rate-limiting
P2
B
initiation
26.4
means
favored,
meets
experimental
results.
ChemCatChem,
Journal Year:
2023,
Volume and Issue:
15(16)
Published: July 4, 2023
Abstract
In
recent
decades,
density
functional
theory
(DFT)
calculations
have
been
extensively
employed
to
investigate
the
mechanism
of
transition
metal‐catalyzed
C−O
activation
reactions.
These
studies
provide
valuable
insights
into
structure‐reactivity/selectivity
correlations
via
theoretical
simulations
and
energy
profile
analysis.
Alcohols,
a
category
molecules
that
are
readily
available
from
biomass
low
cost,
represent
one
most
studied
compounds
in
organic
synthesis.
this
review,
we
brief
overview
DFT
conducted
since
2017
on
C−OH
bond
alcohols
catalyzed
by
metals.
Specifically,
can
be
mainly
divided
four
categories:
free
radical
cleavage,
metal
insertion,
nucleophilic
attack,
β‐OH
elimination.
We
will
also
cover
some
promising
strategies
give
perspective
regarding
future
research
directions
field.
Angewandte Chemie,
Journal Year:
2024,
Volume and Issue:
136(16)
Published: Feb. 13, 2024
Abstract
We
report
a
highly
enantioselective
intermolecular
C−H
bond
silylation
catalyzed
by
phosphoramidite‐ligated
iridium
catalyst.
Under
reagent‐controlled
protocols,
propargylsilanes
resulting
from
C(sp
3
)−H
functionalization,
as
well
the
regioisomeric
and
synthetically
versatile
allenylsilanes,
could
be
obtained
with
excellent
levels
of
enantioselectivity
good
to
control
propargyl/allenyl
selectivity.
In
case
unsymmetrical
dialkyl
acetylenes,
selectivity
for
functionalization
at
less‐hindered
site
was
also
observed.
A
variety
electrophilic
silyl
sources
(R
SiOTf
R
SiNTf
2
),
either
commercial
or
in
situ
‐
generated,
were
used
reagents,
broad
range
simple
functionalized
alkynes,
including
aryl
alkyl
1,3‐enynes,
drug
derivatives
successfully
employed
substrates.
Detailed
mechanistic
experiments
DFT
calculations
suggest
that
an
η
‐propargyl/allenyl
Ir
intermediate
is
generated
upon
π‐complexation‐assisted
deprotonation
undergoes
outer‐sphere
attack
silylating
reagent
give
propargylic
silanes,
latter
step
identified
enantiodetermining
step.
Organic & Biomolecular Chemistry,
Journal Year:
2024,
Volume and Issue:
22(35), P. 7121 - 7127
Published: Jan. 1, 2024
We
introduced,
for
the
first
time,
N
-methoxyamide
directed
proximal
C–H
bond
activation
of
imidazo[1,2-
a
]pyridines
C(sp
2
)–C(sp
)
formation
via
transition
metal
catalysed
approach
to
obtain
C-5
arylated
]pyridines.
