Thiocyanate promoted difunctionalization and cyclization of unsaturated C–C bonds to construct 1-sulfur-2-nitrogen-functionalized alkenes and 2-thiocyanate indolines
Organic & Biomolecular Chemistry,
Год журнала:
2024,
Номер
22(6), С. 1213 - 1218
Опубликована: Янв. 1, 2024
An
unprecedented
one-pot
route
to
achieve
highly
regioselective
1-sulfur-functionalized
2-nitrogen-functionalized
alkenes
and
2-thiocyanate
indolines
from
unsymmetrical
ynamides
(readily
generally
available
amides)
using
the
commercially
inexpensive
iodobenzene
diacetate
(PIDA)
as
oxidant
potassium
thiocyanate
(KSCN)
(SCN)
source
has
been
developed.
The
interconversion
of
isothiocyanate
(NCS)
groups
simultaneously
forms
C-N
C-S
bonds
in
this
metal-free
approach,
while
introducing
important
functional
into
homemade
alkynes.
A
radical-chain
mechanism,
involving
competing
kinetically
controlled
chain
transfer
at
S
atom
sterically-controlled
N
thiocyanogen
molecule
mild
is
proposed.
Язык: Английский
Rhodium and Isothiourea Dual Catalysis: Enantiodivergent Transformation of Terminal Alkynes
Organic Letters,
Год журнала:
2024,
Номер
26(7), С. 1421 - 1425
Опубликована: Фев. 12, 2024
A
dual
rhodium/isothiourea
catalytic
system
was
developed
for
the
enantiodivergent
transformation
of
terminal
alkynes.
Under
synergistic
catalysis,
alkynes
can
be
creatively
utilized
as
precursors
C1-ammonium
enolate
species,
which
subsequently
participate
in
[4
+
2]
and
[2
annulation
reactions
with
α,β-unsaturated
ketimines
or
ketones,
respectively.
wide
range
chiral
lactams
lactones
were
obtained
excellent
yields
stereoselectivities
(up
to
>20:1
dr,
98%
ee).
Язык: Английский
Acid Promoted Tetrafunctionalization of Terminal Alkynes: Geminal Diazidation and Dibromination
Organic Letters,
Год журнала:
2024,
Номер
26(18), С. 3878 - 3882
Опубликована: Апрель 28, 2024
The
synthesis
of
complex
alkanes
by
the
tetrafunctionalization
alkynes
is
limited
and
challenging.
Herein,
an
unprecedented
efficient
geminal
diazidation
dibromination
terminal
developed,
which
provides
novel
access
to
structurally
diverse
organic
azides.
approach
has
exclusive
chemo-
regioselectivity
features
mild
reaction
conditions,
good
tolerance
various
functional
groups,
more
crucially,
no
metal
involved
in
reaction,
thereby
benefiting
late-stage
decoration
medicinal
molecules.
A
mechanistic
study
showed
that
current
proceeds
via
a
radical
pathway.
Язык: Английский