The application and development of cyanating reagents in asymmetric cyanation reactions
Tetrahedron Letters,
Journal Year:
2025,
Volume and Issue:
unknown, P. 155549 - 155549
Published: March 1, 2025
Language: Английский
N-Heterocyclic Carbene-Carbodiimide (NHC-CDI) Adducts: A Systematic Investigation of Electronic Modifications on Kinetic and Thermodynamic Properties of Adduct Association and Dissociation
The Journal of Organic Chemistry,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 20, 2025
N-Heterocyclic
carbene-carbodiimide
(NHC-CDI)
adducts
are
versatile
compounds
that
can
be
used
as
ligands
and
(pre)catalysts,
but
their
systematic
structure-property
relationships
underexplored.
Herein,
we
investigated
how
structural
electronic
variations
on
both
the
NHC
CDI
affect
inherent
kinetic
thermodynamic
properties
of
adducts.
Using
in
situ
carbene
trapping
variable-temperature
NMR
spectroscopy,
measured
rates
dissociation
equilibrium
constants
then
Eyring
van't
Hoff
analyses
to
calculate
ΔG‡
ΔG,
respectively.
Linear
free-energy
indicate
changing
para
position
substituents
yields
a
similar
effect
core.
These
modifications
affected
adducts'
thermodynamics
(ΔG)
more
than
kinetics
(ΔG‡)
were
found
influenced
by
inductive,
rather
resonance,
factors.
Preliminary
results
suggest
steric
threshold
beyond
which
effects
dominate
governing
strength
adduct
bond.
This
investigation
provides
valuable
insight
into
design
NHC-CDIs
for
current
future
applications.
Language: Английский
Hydrocyanation of Non‐Activated Alkenes Without Handling HCN
European Journal of Organic Chemistry,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Aug. 19, 2024
Abstract
The
hydrocyanation
of
alkenes
can
be
considered
a
straightforward
methodology
that
gives
access
to
different
functionalized
organic
chemistry
entities.
This
is
due
nitrile's
high
versatility,
which
easily
undergo
further
transformations.
However,
this
process
has
traditionally
employed
hazardous
hydrogen
cyanide
as
the
agent.
Therefore,
in
last
decades,
protocols
have
been
developed
accomplish
key
transformation
without
needing
handle
HCN.
In
review,
we
aim
gather
most
recent
works
published
couple
decades
regarding
non‐activated
olefins
absence
gaseous
nitrile
source.
addition,
special
attention
paid
reaction
mechanism
working
each
case.
Language: Английский
Reversible C–CN Bond Cleavage by a Formal Dinickel(I) Hydride Cation
Yu Cao,
No information about this author
Neil A. Dodd,
No information about this author
John Bacsa
No information about this author
et al.
Organometallics,
Journal Year:
2024,
Volume and Issue:
43(22), P. 2895 - 2905
Published: Nov. 1, 2024
An
N-heterocyclic
carbene
(NHC)
ligand
supports
a
stable
[Ni2H]+
core,
formally
dinickel(I).
This
diamagnetic
cation
complex
features
bent
hydride
bridge
and
Ni···Ni
distance,
2.9926(5)
Å,
larger
than
two
covalent
radii.
The
displays
weakly
protic
character,
undergoing
deprotonation
by
strong
base
to
form
the
corresponding
(NHC)nickel(0)
dimer.
Its
reaction
with
aliphatic
nitriles
results
in
C–CN
bond
cleavage.
organic
products
of
this
suggest
that
bond-breaking
step
involves
reactive
nickel
alkyl
intermediates
occurs
reversibly.
Language: Английский