- or thermal.
Reactions can be
either ring-opening or ring-closing (
electrocyclization).
Depending on the type of
reaction (photochemical or thermal) and...
- 3-butadiene (a 4π-
electrocyclization) is [π4a]. The
conrotatory electrocyclic ring
opening of
cyclobutene (a
reverse 4π-
electrocyclization) is [σ2a + π2s]...
- g. 65 kJ mol−1 for 4-aminostilbene). The
activation energy of the
electrocyclization is 73 kJ mol−1 for stilbene. Both
processes are
often applied in molecular...
-
azomethine ylides are
capable of [1,5]- and [1,7]-
electrocyclizations. An
example of a [1,7]-
electrocyclization of a diphenylethenyl-substituted azomethine...
-
demonstrated experimentally by
Charles Shoppee to be an
intramolecular electrocyclization and is
outlined below.
Activation of the
ketone by the acid catalyst...
- nucleophile. Its
formation can
otherwise be
viewed as a 2-electron
electrocyclization of a 1,3-dipole,
which can be
captured in
Diels Alder reactions. The...
-
therefore the intermediate's
formation cannot be
viewed as a 2-electron
electrocyclization reaction. The
selectivity is
similar to the
Favorskii rearrangement...
- reactions,
including sigmatropic reactions and cycloadditions, and
electrocyclizations, can be
classified as
either suprafacial or antarafacial, and this...
-
equilibrated to
conformer 8,
which more
readily underwent an 8π-conrotatory
electrocyclization to the
highly strained intermediate 9. The
potential to
release strain...
-
allenyl azide. This
allene rearranges to the
triazafulvene in a 6 pi
electrocyclization. The
exocyclic alkene in this
intermediate is very
electrophilic because...
