Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(20), С. 7648 - 7654
Опубликована: Май 11, 2021
Herein,
we
describe
the
formation
of
quaternary
carbon
centers
with
excellent
diastereoselectivity
via
a
strain-release
protocol.
An
organometallic
species
is
generated
by
Cp*Rh(III)-catalyzed
C–H
activation,
which
then
coupled
strained
bicyclobutanes
(BCBs)
and
prochiral
electrophile
in
three-component
reaction.
This
work
illustrates
rare
example
BCBs
transition
metal
catalysis
demonstrates
their
broad
potential
to
access
novel
reaction
pathways.
The
method
developed
exhibits
ample
functional
group
tolerance,
products
can
be
further
transformed
into
valuable
α-quaternary
β-lactones.
Preliminary
mechanistic
investigations
suggest
twofold
C–C
bond
cleavage
sequence
involving
σ-bond
insertion
an
ensuing
β-carbon
elimination
event.
Journal of the American Chemical Society,
Год журнала:
2022,
Номер
144(18), С. 7988 - 7994
Опубликована: Апрель 27, 2022
Saturated
bicycles
are
becoming
ever
more
important
in
the
design
and
development
of
new
pharmaceuticals.
Here
a
strategy
for
synthesis
bicyclo[2.1.1]hexanes
is
described.
These
significant
because
they
have
defined
exit
vectors,
yet
many
substitution
patterns
underexplored
as
building
blocks.
The
process
involves
sensitization
bicyclo[1.1.0]butane
followed
by
cycloaddition
with
an
alkene.
scope
mechanistic
details
method
discussed.
Chemical Science,
Год журнала:
2022,
Номер
13(40), С. 11721 - 11737
Опубликована: Янв. 1, 2022
A
flurry
of
reports
for
preparing,
functionalizing,
and
using
bicyclo[1.1.0]butanes
(BCBs)
have
positioned
them
to
be
powerful
synthons
with
numerous
applications.
This
review
discusses
the
recent
developments
regarding
this
strained
carbocycle.
Communications Chemistry,
Год журнала:
2023,
Номер
6(1)
Опубликована: Янв. 12, 2023
Abstract
Bicyclobutanes
are
among
the
most
highly
strained
isolable
organic
compounds
and
their
associated
low
activation
barriers
to
reactivity
make
them
intriguing
building-blocks
in
chemistry.
In
recent
years,
numerous
creative
synthetic
strategies
exploiting
heightened
have
been
presented
these
discoveries
often
gone
hand-in-hand
with
development
of
more
practical
routes
for
synthesis.
Their
proclivity
as
strain-release
reagents
through
weak
central
C–C
bond
has
harnessed
a
variety
addition,
rearrangement
insertion
reactions,
providing
rapid
access
rich
tapestry
complex
molecular
scaffolds.
This
review
will
provide
an
overview
different
options
available
bicyclobutane
synthesis,
main
classes
that
can
be
prepared
from
bicyclobutanes,
modes
used.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(22), С. 12324 - 12332
Опубликована: Май 26, 2023
Dearomative
photocycloadditions
are
valuable
chemical
transformations,
serving
as
an
efficient
platform
to
create
three-dimensional
molecular
complexity.
However,
the
photolability
of
original
addition
product
especially
within
context
ortho
cycloadditions
often
causes
undesired
consecutive
rearrangements,
rendering
these
cycloadducts
elusive.
Herein,
we
report
ortho-selective
intermolecular
photocycloaddition
bicyclic
aza-arenes
including
(iso)quinolines,
quinazolines,
and
quinoxalines
by
utilizing
a
strain-release
approach.
With
bicyclo[1.1.0]butanes
coupling
partners,
this
dearomative
[2π
+
2σ]
cycloaddition
enables
straightforward
construction
C(sp3)-rich
bicyclo[2.1.1]hexanes
directly
connected
N-heteroarenes.
Photophysical
experiments
DFT
calculations
revealed
origin
selectivity
indicate
that,
in
originally
proposed
energy
transfer
or
direct
excitation
pathways,
chain
reaction
mechanism
is
operative
depending
on
conditions.
Chemical Reviews,
Год журнала:
2024,
Номер
124(5), С. 2441 - 2511
Опубликована: Фев. 21, 2024
Boron-containing
compounds
(BCC)
have
emerged
as
important
pharmacophores.
To
date,
five
BCC
drugs
(including
boronic
acids
and
boroles)
been
approved
by
the
FDA
for
treatment
of
cancer,
infections,
atopic
dermatitis,
while
some
natural
are
included
in
dietary
supplements.
Boron's
Lewis
acidity
facilitates
a
mechanism
action
via
formation
reversible
covalent
bonds
within
active
site
target
proteins.
Boron
has
also
employed
development
fluorophores,
such
BODIPY
imaging,
carboranes
that
potential
neutron
capture
therapy
agents
well
novel
diagnostics
therapy.
The
utility
synthetic
become
multifaceted,
breadth
their
applications
continues
to
expand.
This
review
covers
many
uses
targets
boron
medicinal
chemistry.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(48)
Опубликована: Авг. 16, 2023
Abstract
Herein,
we
develop
a
new
approach
to
directly
access
architecturally
complex
polycyclic
indolines
from
readily
available
indoles
and
bicyclo[1.1.0]butanes
(BCBs)
through
formal
cycloaddition
promoted
by
commercially
Lewis
acids.
The
reaction
proceeded
stepwise
pathway
involving
nucleophilic
addition
of
BCBs
followed
an
intramolecular
Mannich
form
rigid
indoline‐fused
structures,
which
resemble
indole
alkaloids.
This
tolerated
wide
range
BCBs,
thereby
allowing
the
one‐step
construction
various
indoline
polycycles
containing
up
four
contiguous
quaternary
carbon
centers.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(30), С. 16508 - 16516
Опубликована: Июль 20, 2023
Enantioenriched
organoboron
intermediates
are
important
building
blocks
in
organic
synthesis
and
drug
discovery.
Recently,
transition
metal-catalyzed
enantioselective
1,2-metalate
rearrangements
of
alkenylboronates
have
emerged
as
an
attractive
protocol
to
access
these
valuable
reagents
by
installing
two
different
carbon
fragments
across
C═C
π-bonds.
Herein,
we
report
the
development
iridium-catalyzed
asymmetric
allylation-induced
rearrangement
bicyclo[1.1.0]butyl
(BCB)
boronate
complexes
enabled
strain
release,
which
allows
difunctionalization
C-C
σ-bonds,
including
dicarbonation
carboboration.
This
provides
a
variety
enantioenriched
three-dimensional
1,1,3-trisubstituted
cyclobutane
products
bearing
boronic
ester
that
can
be
readily
derivatized.
Notably,
reaction
gives
trans
diastereoisomers
result
from
anti-addition
σ-bond,
is
contrast
syn-additions
observed
for
reactions
promoted
PdII-aryl
other
electrophiles
our
previous
works.
The
diastereoselectivity
has
been
rationalized
based
on
combination
experimental
data
density
functional
theory
calculations,
suggest
BCB
highly
nucleophilic
react
via
early
states
with
low
activation
barriers.
Chemistry - A European Journal,
Год журнала:
2023,
Номер
29(29)
Опубликована: Фев. 14, 2023
The
use
of
metalated
(aza)bicyclo[1.1.0]butanes
in
synthesis
is
currently
experiencing
a
renaissance,
as
evidenced
by
the
numerous
reports
last
5
years
that
have
relied
on
such
intermediates
to
undergo
unique
transformations
or
generate
novel
fragments.
Since
their
discovery,
these
species
been
demonstrated
participate
wide
range
reactions
with
carbon
and
heteroatom
electrophiles,
well
metal
complexes,
facilitate
rapid
diversification
(aza)bicyclo[1.1.0]butane-containing
compounds.
Key
this
relative
acidity
bridgehead
C-H
bonds
which
promotes
facile
deprotonation
subsequent
functionalization
an
unsubstituted
position
framework
via
intermediacy
(aza)bicyclo[1.1.0]butane.
Additionally,
late-stage
incorporation
deuterium
atoms
strained
fragments
has
led
elucidation
reaction
mechanisms
involve
bicycles.
continued
investigation
into
inimitable
reactivity
bicycles
will
cement
importance
within
field
organometallic
chemistry.
Tetrahedron Chem,
Год журнала:
2024,
Номер
9, С. 100070 - 100070
Опубликована: Фев. 28, 2024
Bicyclo[1.1.0]butanes
(BCBs)
and
[1.1.1]propellanes
(tricyclo[1.1.1.01,3]pentanes,
TCPs)
are
structurally
unique
compounds
with
different
chemical
properties.
Strain-release
driven
reactions
have
emerged
as
an
atom-
step-economic
strategy
for
the
organic
synthesis.
Using
this
strategy,
a
variety
of
functional
ring
molecules
been
efficiently
synthesized,
including
various
cyclobutane
molecules,
bicyclo[2.1.1]hexanes,
bicyclo[1.1.1]pentanes,
others.
More
specifically,
these
strain
release-driven
include
aspects
nucleophilic
addition,
radical
electrophilic
or
transition
metal
catalysis.
This
review
will
discuss
recent
developments
in
strain-release
transformations
bicyclo[1.1.0]butanes
[1.1.1]propellanes.
