5 research outputs found
A Novel Lewis Acid Catalyzed [3 + 3]-Annulation Strategy for the Syntheses of Tetrahydro-β-Carbolines and Tetrahydroisoquinolines
No full textA novel Lewis acid catalyzed [3 + 3]-annulation process for the efficient syntheses of both tetrahydro-β-carbolines and tetrahydroisoquinolines from readily available benzylic alcohols and aziridines was developed, which would be a highly valuable complement to the widely used Pictet–Spengler reaction. A probable mechanism was proposed based on the isolation and characterization of two key intermediates. This strategy enables facile access to important alkaloid frameworks not easily available with other known methods
Lewis Acid Catalyzed Cascade Reaction to Carbazoles and Naphthalenes via Dehydrative [3 + 3]-Annulation
No full textA novel Lewis acid catalyzed dehydrative
[3 + 3]-annulation of
readily available benzylic alcohols and propargylic alcohols was developed
to give polysubstituted carbazoles and naphthalenes in moderate to
good yields with water as the only byproduct. The reaction was presumed
to proceed via a cascade process involving Friedel–Crafts-type
allenylation, 1,5-hydride shift, 6π-eletrocyclization, and Wagner–Meerwein
rearrangement
Copper(I)-Catalyzed Kinetic Resolution of <i>N</i>‑Sulfonylaziridines with Indoles: Efficient Construction of Pyrroloindolines
No full textThe first Lewis acid
catalyzed [3 + 2] annulation of indoles and
2-aryl-<i>N</i>-tosylaziridines was realized by using copper(I)/chiral
diphosphine complexes as a catalyst. With this method, a variety of
uniquely substituted chiral pyrroloindolines bearing multiple contiguous
stereogenic centers were facilely accessed in a straightforward, high-yielding,
and highly stereoselective way under mild conditions
Synthesis, Structure, and Reactivity of Lanthanide Complexes Incorporating Indolyl Ligands in Novel Hapticities
No full textThe
chemistry of interactions of 2-(2,6-diisopropylphenylaminomethylene)indole
ligand (<b>1</b>) with europium and ytterbium amides is described.
Reaction of 2-(2,6-diisopropylphenylaminomethylene)indole 2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NHCH<sub>2</sub>)C<sub>8</sub>H<sub>5</sub>NH (<b>1</b>) with europium amide
[(Me<sub>3</sub>Si)<sub>2</sub>N]<sub>3</sub>Eu<sup>III</sup>(μ-Cl)Li(THF)<sub>3</sub> afforded a novel europium(II) complex formulated as {[μ-η<sup>6</sup>:η<sup>1</sup>:η<sup>1</sup>-2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH)C<sub>8</sub>H<sub>5</sub>N]Eu[2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH)C<sub>8</sub>H<sub>5</sub>N]}<sub>2</sub> (<b>2</b>), having a bridged indolyl ligand in the novel μ-η<sup>6</sup>:η<sup>1</sup>:η<sup>1</sup> hapticities with
the reduction of europium(III) to europium(II) and the oxidation of
amino to imino group. Reaction of 2-(2,6-diisopropylphenylaminomethylene)indole
2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NHCH<sub>2</sub>)C<sub>8</sub>H<sub>5</sub>NH (<b>1</b>) with
ytterbium(III) amide [(Me<sub>3</sub>Si)<sub>2</sub>N]<sub>3</sub>Yb<sup>III</sup>(μ-Cl)Li(THF)<sub>3</sub> produced the only
deprotonated ytterbium(III) complex formulated as [2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH<sub>2</sub>)C<sub>8</sub>H<sub>5</sub>N]Yb[N(SiMe<sub>3</sub>)<sub>2</sub>](THF)<sub>2</sub> (<b>3</b>), having an η<sup>1</sup> hapticity
indolyl ligand. Reaction of <b>2</b> with formamidine [(2,6-Me<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NCHNH(C<sub>6</sub>H<sub>3</sub>Me<sub>2</sub>-2,6)] produced {[μ-η<sup>3</sup>:η<sup>1</sup>:η<sup>1</sup>-2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH)C<sub>8</sub>H<sub>5</sub>N]Eu[(2,6-Me<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NCHN(C<sub>6</sub>H<sub>3</sub>Me<sub>2</sub>-2,6)](THF)}<sub>2</sub> (<b>4</b>), which has
a bridged indolyl ligand in the novel μ-η<sup>3</sup>:η<sup>1</sup>:η<sup>1</sup> hapticities, whereas the reaction of <b>2</b> with the more sterically bulky formamidine [(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NCHNH(C<sub>6</sub>H<sub>3</sub><i>i</i>-Pr<sub>2</sub>-2,6)] afforded complex
{[μ-η<sup>2</sup>:η<sup>1</sup>:η<sup>1</sup>-2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH)C<sub>8</sub>H<sub>5</sub>N]Eu[(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NCHN(C<sub>6</sub>H<sub>3</sub><i>i</i>-Pr<sub>2</sub>-2,6)](THF)}<sub>2</sub> (<b>5</b>), having the indolyl ligand in the novel μ-η<sup>2</sup>:η<sup>1</sup>:η<sup>1</sup> hapticities. The
results represent the first example of organometallic complexes having
indolyl ligands in the novel μ-η<sup>6</sup>:η<sup>1</sup>:η<sup>1</sup>, μ-η<sup>3</sup>:η<sup>1</sup>:η<sup>1</sup>, and μ-η<sup>2</sup>:η<sup>1</sup>:η<sup>1</sup> bonding modes with metal
Synthesis, Structure, and Reactivity of Lanthanide Complexes Incorporating Indolyl Ligands in Novel Hapticities
No full textThe
chemistry of interactions of 2-(2,6-diisopropylphenylaminomethylene)indole
ligand (<b>1</b>) with europium and ytterbium amides is described.
Reaction of 2-(2,6-diisopropylphenylaminomethylene)indole 2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NHCH<sub>2</sub>)C<sub>8</sub>H<sub>5</sub>NH (<b>1</b>) with europium amide
[(Me<sub>3</sub>Si)<sub>2</sub>N]<sub>3</sub>Eu<sup>III</sup>(μ-Cl)Li(THF)<sub>3</sub> afforded a novel europium(II) complex formulated as {[μ-η<sup>6</sup>:η<sup>1</sup>:η<sup>1</sup>-2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH)C<sub>8</sub>H<sub>5</sub>N]Eu[2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH)C<sub>8</sub>H<sub>5</sub>N]}<sub>2</sub> (<b>2</b>), having a bridged indolyl ligand in the novel μ-η<sup>6</sup>:η<sup>1</sup>:η<sup>1</sup> hapticities with
the reduction of europium(III) to europium(II) and the oxidation of
amino to imino group. Reaction of 2-(2,6-diisopropylphenylaminomethylene)indole
2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NHCH<sub>2</sub>)C<sub>8</sub>H<sub>5</sub>NH (<b>1</b>) with
ytterbium(III) amide [(Me<sub>3</sub>Si)<sub>2</sub>N]<sub>3</sub>Yb<sup>III</sup>(μ-Cl)Li(THF)<sub>3</sub> produced the only
deprotonated ytterbium(III) complex formulated as [2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH<sub>2</sub>)C<sub>8</sub>H<sub>5</sub>N]Yb[N(SiMe<sub>3</sub>)<sub>2</sub>](THF)<sub>2</sub> (<b>3</b>), having an η<sup>1</sup> hapticity
indolyl ligand. Reaction of <b>2</b> with formamidine [(2,6-Me<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NCHNH(C<sub>6</sub>H<sub>3</sub>Me<sub>2</sub>-2,6)] produced {[μ-η<sup>3</sup>:η<sup>1</sup>:η<sup>1</sup>-2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH)C<sub>8</sub>H<sub>5</sub>N]Eu[(2,6-Me<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NCHN(C<sub>6</sub>H<sub>3</sub>Me<sub>2</sub>-2,6)](THF)}<sub>2</sub> (<b>4</b>), which has
a bridged indolyl ligand in the novel μ-η<sup>3</sup>:η<sup>1</sup>:η<sup>1</sup> hapticities, whereas the reaction of <b>2</b> with the more sterically bulky formamidine [(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NCHNH(C<sub>6</sub>H<sub>3</sub><i>i</i>-Pr<sub>2</sub>-2,6)] afforded complex
{[μ-η<sup>2</sup>:η<sup>1</sup>:η<sup>1</sup>-2-(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>NCH)C<sub>8</sub>H<sub>5</sub>N]Eu[(2,6-<i>i</i>-Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)NCHN(C<sub>6</sub>H<sub>3</sub><i>i</i>-Pr<sub>2</sub>-2,6)](THF)}<sub>2</sub> (<b>5</b>), having the indolyl ligand in the novel μ-η<sup>2</sup>:η<sup>1</sup>:η<sup>1</sup> hapticities. The
results represent the first example of organometallic complexes having
indolyl ligands in the novel μ-η<sup>6</sup>:η<sup>1</sup>:η<sup>1</sup>, μ-η<sup>3</sup>:η<sup>1</sup>:η<sup>1</sup>, and μ-η<sup>2</sup>:η<sup>1</sup>:η<sup>1</sup> bonding modes with metal
