Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(24), P. 5192 - 5195
Published: June 10, 2024
A
double
deoxygenative
C-N
coupling
protocol
has
been
developed
by
employing
acyloxyamines
through
N-O
bond
activation.
The
formation
under
mild
reaction
conditions,
NiCl
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(18)
Published: Feb. 25, 2023
Herein,
we
describe
a
practical
protocol
for
the
removal
of
alcohol
functional
groups
through
reductive
cleavage
their
benzoate
ester
analogs.
This
transformation
requires
strong
single
electron
transfer
(SET)
reductant
and
means
to
accelerate
slow
fragmentation
following
substrate
reduction.
To
accomplish
this,
developed
photocatalytic
system
that
generates
potent
from
formate
salts
alongside
Brønsted
or
Lewis
acids
promote
reduced
intermediate.
deoxygenation
procedure
is
effective
across
structurally
electronically
diverse
alcohols
enables
variety
difficult
net
transformations.
no
precautions
exclude
air
moisture
remains
efficient
on
multigram
scale.
Finally,
can
be
adapted
one-pot
benzoylation-deoxygenation
sequence
enable
direct
deletion.
Mechanistic
studies
validate
role
acidic
additives
key
C(sp
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: March 9, 2024
Abstract
Achieving
selective
hydrodeoxygenation
of
α,
β-unsaturated
carbonyl
groups
to
alkenes
poses
a
substantial
challenge
due
the
presence
multiple
functional
groups.
In
this
study,
we
develop
ZnNC-X
catalyst
(X
represents
calcination
temperature)
that
incorporates
both
Lewis
acidic-basic
sites
and
Zn-N
x
address
challenge.
Among
variants,
ZnNC-900
exhibits
impressive
selectivity
for
in
compounds,
achieving
up
94.8%
selectivity.
Through
comprehensive
mechanism
investigations
characterization,
identify
as
responsible
hydrogenation
C=O
bonds,
while
facilitate
subsequent
step.
Furthermore,
displays
broad
applicability
across
diverse
range
unsaturated
compounds.
These
findings
not
only
offer
valuable
insights
into
design
effective
catalysts
controlling
alkene
but
also
extend
scope
sustainable
transformations
synthetic
chemistry.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(20), P. 11449 - 11456
Published: May 4, 2023
Perfluoroalkyl
compounds
are
persistent
environmental
pollutants
due
to
their
strong
C(sp3)-F
bonds.
Hydrodefluorination
has
emerged
as
a
potential
alternative
disposal
method
for
perfluoroalkyl
compounds.
Although
the
transformation
of
trifluoromethyl
arenes
into
corresponding
methyl
been
studied
by
several
research
groups,
hydrodefluorination
reactions
longer
chains
remain
rare.
Herein,
we
report
exhaustive
pentafluoroethyl
and
longer-chain
analogues
using
molecular
nickel
catalysis.
Despite
cleavage
multiple
bonds,
reaction
already
proceeds
upon
gentle
heating
(60
°C).
A
mechanistic
investigation
indicated
that
via
benzylic
followed
homobenzylic
ones.
We
reveal
roles
Ni
catalyst,
which
include
C-F
bond
cleavage,
promotion
HF
elimination,
hydrosilylation.
ACS Catalysis,
Journal Year:
2023,
Volume and Issue:
13(10), P. 6787 - 6794
Published: May 3, 2023
Efficient
deoxygenative
silylation
of
C(sp3)–O
bonds
with
hydrosilanes
by
supported
Au
catalysts
is
described.
Gold
nanoparticles
on
TiO2
enabled
various
to
be
used
as
sources
silyl
groups
in
C–Si
cross-coupling
reactions.
A
variety
alkyl
acetates
and
propargyl
carbonates
participated
the
Au-catalyzed
reactions
furnish
corresponding
allenylsilanes
high
yields.
In
addition,
Au/TiO2
was
also
effective
for
ring-opening
cyclic
ethers.
detailed
mechanistic
investigation
corroborated
that
title
reaction
involves
formation
radical
intermediates,
cooperation
single-electron
transfer
Lewis
acid
sites
at
surface
metal
oxides
responsible
unusual
reactivity
specific
C(sp3)–Si
bond
formation.
Organic Letters,
Journal Year:
2023,
Volume and Issue:
25(35), P. 6571 - 6576
Published: Aug. 30, 2023
A
practical
and
precise
method
for
visible-light-promoted
deoxygenative
deuteration
of
common
aliphatic
alcohols
using
D2O
as
the
deuterium
source
is
reported.
Upon
intermediacy
xanthate
anions,
a
variety
primary,
secondary,
tertiary
can
be
facilely
transformed
into
deuterioalkanes
with
excellent
D-incorporation
at
predicted
sites.
The
deoxygenation
sequence
catalyzed
by
in
situ
formed
deuterated
2-mercaptopyridine,
which
plays
dual
roles
atom
transfer
catalyst
an
electron
shuttle
well.
ACS Catalysis,
Journal Year:
2024,
Volume and Issue:
14(6), P. 4249 - 4264
Published: March 5, 2024
The
development
of
simple
and
general
catalytic
methods
using
abundant
base
metal
catalysts
for
the
deoxygenation
organic
compounds
valorization
biomass
chemical
synthesis
remains
a
formidable
challenge.
Cobalt
pincer-catalyzed
reductive
aldehydes,
ketones,
alcohols,
ethers
to
their
corresponding
alkanes
is
reported.
Biomass-derived
were
deoxygenated
methylarenes.
This
system
employs
diethylsilane
as
reductant
requires
substoichiometric
amount
base.
Investigations
revealed
initial
deprotonation
amine
arm
on
catalyst,
catalysis
begins
with
Si–H
activation
silane
facilitated
by
amine-amide
metal–ligand
cooperation.
In
situ-formed
Co–H
species
carry
out
hydrosilylation
carbonyl
compounds,
dehydrosilylation
hydrosilanolysis
ethers,
resulting
in
common
arylmethylsilyl
or
alkylsilyl
ether
intermediates.
Further,
reaction
leads
formation
siloxane
oligomers.
DFT
study
reveals
closely
lying
singlet–triplet
electronic
states
different
intermediates
facilitating
mechanism
spin
surfaces,
verified
through
located
minimum
energy
crossing
points
(MECPs).
case
alcohol,
another
low
pathway
where
amide
pincer,
instead
hydride,
can
abstract
hydroxy
proton
enable
ChemSusChem,
Journal Year:
2022,
Volume and Issue:
15(9)
Published: April 7, 2022
Biobased
raw
materials,
such
as
carbohydrates,
amino
acids,
nucleotides,
or
lipids
contain
valuable
functional
groups
with
oxygen
and
nitrogen
atoms.
An
abundance
of
many
the
same
type,
primary
secondary
hydroxy
in
however,
limits
synthetic
usefulness
if
similar
reactivities
cannot
be
differentiated.
Therefore,
selective
defunctionalization
highly
functionalized
biobased
starting
materials
to
differentially
compounds
can
provide
a
sustainable
access
chiral
synthons,
even
case
products
fewer
groups.
Selective
reactions,
without
affecting
other
are
fundamental
interest
for
biocatalytic
reactions.
Controlled
defunctionalizations
attractive
obtaining
platform
chemicals
building
blocks.
The
removal
groups,
an
important
feature
natural
metabolic
pathways,
also
utilized
systemic
strategy
metabolite
synthesis.
Organic Letters,
Journal Year:
2022,
Volume and Issue:
24(46), P. 8459 - 8464
Published: Nov. 10, 2022
Herein
we
report
a
Ti-catalyzed
direct
dehydroxylation
of
tertiary
aliphatic
alcohols
under
mild
reaction
conditions,
forging
Barton-type
deoxygenation
products.
This
protocol
tolerates
wide
range
functional
groups,
including
primary
alkyl
chloride
and
carbonyl
groups.
It
allows
for
selective
in
diols
the
formation
deuterated
products
with
moderate
deuterium
incorporation.
The
efficient
modification
several
drugs
natural
(or
their
derivatives)
highlights
synthetic
utility
this
method.