Organic Reaction Mechanisms/Organic reaction mechanisms,
Journal Year:
2020,
Volume and Issue:
unknown, P. 501 - 526
Published: July 24, 2020
This
Chapter
Contains
Sections
titled:
2
+
2-Cycloaddition
3-Cycloaddition
4-Cycloaddition
Miscellaneous
References
chapter
presents
an
extensive
review
of
the
use
organocatalysts,
such
as
diarylpropinol
silyl
ethers,
in
asymmetric
cycloaddition
reactions.
The
includes
2+2-,
3+2-,
and
4+2-cycloadditions
which
do
not
require
loss
a
leaving
group
to
form
cyclic
compound.
reports
comprehensive
gold-catalysed
enantioselective
annulations
including
cycloadditions,
cyclizations
C–C
multiple
bonds
with
tethered
nucleophiles,
cycloisomerization
or
cyclization
enynes,
tandem
annulations.
photosensitized
regioselective
2+2-cycloaddition
cinnamates,
chalcones,
styrenes
produced
substituted
cyclobutanes
high
yields
good
regioselectivity.
stereoselective
organo-catalysed
3+2-cycloaddition
donor–acceptor
cyclopropanes
mono-
poly-substituted
nitroolefins
functionalized
cyclopentanes
three
contiguous
stereocentres
stereoselectivity.
A
4+2-cycloaddition
reactions
ynamines
ynamides
providing
complex
aromatics
N-containing
heterocycles
single
step
has
been
published.
Angewandte Chemie International Edition,
Journal Year:
2018,
Volume and Issue:
57(32), P. 10338 - 10342
Published: June 24, 2018
The
first
example
of
(3+3)-annulation
two
different
three-membered
rings
is
reported
herein.
Donor-acceptor
cyclopropanes
in
reaction
with
diaziridines
were
found
to
afford
perhydropyridazine
derivatives
high
yields
and
diastereoselectivity
under
mild
Lewis
acid
catalysis.
disclosed
applicable
for
the
broad
substrate
scope
exhibits
an
excellent
functional
group
tolerance.
Angewandte Chemie,
Journal Year:
2018,
Volume and Issue:
130(32), P. 10495 - 10499
Published: June 24, 2018
Abstract
The
first
example
of
(3+3)‐annulation
two
different
three‐membered
rings
is
reported
herein.
Donor‐acceptor
cyclopropanes
in
reaction
with
diaziridines
were
found
to
afford
perhydropyridazine
derivatives
high
yields
and
diastereoselectivity
under
mild
Lewis
acid
catalysis.
disclosed
applicable
for
the
broad
substrate
scope
exhibits
an
excellent
functional
group
tolerance.
Organic Letters,
Journal Year:
2019,
Volume and Issue:
21(10), P. 3822 - 3827
Published: May 8, 2019
For
the
first
time,
an
efficient
one-pot
method
for
construction
of
angularly
fused
5–6–5
aza-tricyclic
framework
has
been
developed
in
a
highly
stereoselective
manner.
This
domino
reaction
is
novel
combination
aza-Piancatelli
rearrangement
and
intramolecular
Diels–Alder
reaction,
which
readily
furnishes
hexahydro-2a,5-epoxy-cyclopenta[cd]isoindole
adducts,
bearing
six
contiguous
stereogenic
centers
very
good
yields.
The
BBr3-mediated
cleavage
oxa-bridged
adduct
results
formation
octahydro-1H-cyclopenta[cd]isoindole,
BCE
core
gracilamine
alkaloid.
Organic Letters,
Journal Year:
2018,
Volume and Issue:
20(9), P. 2517 - 2521
Published: April 17, 2018
(−)-Englerin
A
was
synthesized
in
20
steps
from
the
commercially
available
material
(R)-(+)-limonene.
In
addition,
(−)-englerin
B,
(+)-orientalol
E/F
and
(−)-oxyphyllol
were
obtained
intermediate
route.
The
key
include
a
hydroxyl-directing
stereoselective
regioselective
intramolecular
cyclopropanation
multi-gram-scale
formal
[3
+
2]
cross
cycloaddition
([3
2]-IMCC)
of
cyclopropane
1,1-diester
with
carbonyl.
precursor
7,10-diastereoisomer
englerins
also
obtained.
Organic Letters,
Journal Year:
2019,
Volume and Issue:
21(7), P. 2356 - 2359
Published: March 20, 2019
An
impressive
and
new
[3
+
3]-cycloaddition
of
α-diazocarbonyl
compounds
with
N-tosylaziridines
via
synergetic
catalysis
AgOTf
Cu(OAc)2
has
been
well
described,
which
offers
efficient
access
to
highly
substituted
2
H-1,4-oxazine
derivatives.
A
variety
were
compatible
substrates
convenient
operations
under
mild
reaction
conditions.
Chemical Communications,
Journal Year:
2021,
Volume and Issue:
57(84), P. 11092 - 11095
Published: Jan. 1, 2021
Tandem
reactions
of
the
yttrium(iii)
catalyzed
ring-opening
reaction
2,2'-diester
aziridines
with
3-(2-isocyanoethyl)indoles
and
subsequent
Friedel-Crafts/Mannich/desulfonylation
were
reported.
A
series
polycyclic
spiroindolines
containing
tetrahydro-β-carbolines
obtained
in
moderate
to
excellent
yields
(56-92%)
one
step
under
mild
conditions.
possible
catalytic
mechanism
was
also
proposed.
Chemical Communications,
Journal Year:
2023,
Volume and Issue:
59(55), P. 8572 - 8575
Published: Jan. 1, 2023
A
new
type
of
metal-free
[5+1]
cycloaddition
reaction
donor-acceptor
aziridines
with
2-(2-isocyanoethyl)indoles
is
reported
herein.
This
method
exhibits
broad
substrate
scope
and
atom-economy.
series
2H-1,4-oxazines
containing
an
indole
heterocycle
skeleton
were
obtained
in
up
to
92%
yield
under
mild
conditions.
Control
experiments
revealed
that
free
N-H
crucial
for
the
above
transformations.
The
theoretical
calculation
studies
provided
guidance
on
in-depth
insight
into
mechanism
hydrogen-bond
between
carbonyl
group
was
identified
lower
energy
barrier
transition
states.
Advanced Synthesis & Catalysis,
Journal Year:
2021,
Volume and Issue:
363(10), P. 2619 - 2624
Published: Feb. 26, 2021
Abstract
A
Y(OTf)
3
‐catalyzed
[3+2]
cycloaddition
of
1,3,5‐triazinanes
with
donor‐acceptor
aziridines
has
been
developed,
accessing
diversely
substituted
imidazolidines
high
efficiency.
Mechanistic
investigations
support
the
formation
through
an
S
N
1‐like
pathway.
Furthermore,
these
exhibit
promising
anti‐tumor
activity
against
a
series
human
cancer
cell
lines.
magnified
image
