3 research outputs found
Heterobi- and Trimetallic Cerium(IV) <i>tert</i>-Butoxides with Mono‑, Di‑, and Trivalent Metals (<i>M</i> = K(I), Ge(II), Sn(II), Pb(II), Al(III), Fe(III))
The
reaction of <i>C</i>erium <i>A</i>mmonium <i>N</i>itrate (CAN) with varying amounts of KO<sup><i>t</i></sup>Bu produced homometallic Ce(O<sup><i>t</i></sup>Bu)<sub>4</sub>(NC<sub>5</sub>H<sub>5</sub>)<sub>2</sub> (<b>1</b>)
and the heterometallic derivative KCe<sub>2</sub>(O<sup><i>t</i></sup>Bu)<sub>10</sub> (<b>3</b>) characterized by X-ray diffraction
and NMR spectroscopy. The oxo-alkoxide cluster Ce<sub>3</sub>O(O<sup><i>t</i></sup>Bu)<sub>9</sub> (<b>2</b>) was obtained
from a solution of cerium(IV) tetrakis(<i>tert</i>-butoxide)
in <i>n</i>-heptane under stringent precautions to avoid
any adventitious hydrolysis. Lewis acid-base reactions of in situ
generated Ce(O<sup><i>t</i></sup>Bu)<sub>4</sub>(THF)<sub>2</sub> (THF = tetrahydrofuran) with bi- and trivalent metal alkoxides
[<i>M</i>(O<sup><i>t</i></sup>Bu)<sub><i>x</i></sub>]<sub><i>n</i></sub> (<i>M</i> = Ge, Sn; <i>x</i> = 2; <i>n</i> = 2; <i>M</i> = Pb, <i>x</i> = 2; <i>n</i> = 3; <i>M</i> = Al, Fe; <i>x</i> = 3; <i>n</i> =
2) resulted in volatile products of the general formula <i>M</i>Ce(O<sup><i>t</i></sup>Bu)<sub>4+<i>x</i></sub> (<i>M</i> = Al (<b>4</b>), Fe (<b>5</b>); <i>x</i> = 3; <i>M</i> = Ge (<b>8</b>), Sn (<b>9</b>), Pb (<b>10</b>); <i>x</i> = 2) in high
yields. By dissolving <b>4</b> and <b>5</b> in pyridine
the solvent adducts <i>M</i>Ce(O<sup><i>t</i></sup>Bu)<sub>7</sub>(NC<sub>5</sub>H<sub>5</sub>) (<i>M</i> =
Al (<b>6</b>), Fe (<b>7</b>)) were formed, whereas <b>8</b> and <b>9</b> reacted with Mo(CO)<sub>6</sub> in boiling
toluene to yield the termetallic complexes (CO)<sub>5</sub>Mo<i>M</i>(μ<sub>2</sub>-O<sup><i>t</i></sup>Bu)<sub>3</sub>Ce(O<sup><i>t</i></sup>Bu)<sub>3</sub> (<i>M</i> = Ge (<b>11</b>), Sn (<b>12</b>)). The new
compounds were characterized by comprehensive spectral studies, mass
spectroscopy, and single crystal X-ray diffraction analysis
Heterobi- and Trimetallic Cerium(IV) <i>tert</i>-Butoxides with Mono‑, Di‑, and Trivalent Metals (<i>M</i> = K(I), Ge(II), Sn(II), Pb(II), Al(III), Fe(III))
The
reaction of <i>C</i>erium <i>A</i>mmonium <i>N</i>itrate (CAN) with varying amounts of KO<sup><i>t</i></sup>Bu produced homometallic Ce(O<sup><i>t</i></sup>Bu)<sub>4</sub>(NC<sub>5</sub>H<sub>5</sub>)<sub>2</sub> (<b>1</b>)
and the heterometallic derivative KCe<sub>2</sub>(O<sup><i>t</i></sup>Bu)<sub>10</sub> (<b>3</b>) characterized by X-ray diffraction
and NMR spectroscopy. The oxo-alkoxide cluster Ce<sub>3</sub>O(O<sup><i>t</i></sup>Bu)<sub>9</sub> (<b>2</b>) was obtained
from a solution of cerium(IV) tetrakis(<i>tert</i>-butoxide)
in <i>n</i>-heptane under stringent precautions to avoid
any adventitious hydrolysis. Lewis acid-base reactions of in situ
generated Ce(O<sup><i>t</i></sup>Bu)<sub>4</sub>(THF)<sub>2</sub> (THF = tetrahydrofuran) with bi- and trivalent metal alkoxides
[<i>M</i>(O<sup><i>t</i></sup>Bu)<sub><i>x</i></sub>]<sub><i>n</i></sub> (<i>M</i> = Ge, Sn; <i>x</i> = 2; <i>n</i> = 2; <i>M</i> = Pb, <i>x</i> = 2; <i>n</i> = 3; <i>M</i> = Al, Fe; <i>x</i> = 3; <i>n</i> =
2) resulted in volatile products of the general formula <i>M</i>Ce(O<sup><i>t</i></sup>Bu)<sub>4+<i>x</i></sub> (<i>M</i> = Al (<b>4</b>), Fe (<b>5</b>); <i>x</i> = 3; <i>M</i> = Ge (<b>8</b>), Sn (<b>9</b>), Pb (<b>10</b>); <i>x</i> = 2) in high
yields. By dissolving <b>4</b> and <b>5</b> in pyridine
the solvent adducts <i>M</i>Ce(O<sup><i>t</i></sup>Bu)<sub>7</sub>(NC<sub>5</sub>H<sub>5</sub>) (<i>M</i> =
Al (<b>6</b>), Fe (<b>7</b>)) were formed, whereas <b>8</b> and <b>9</b> reacted with Mo(CO)<sub>6</sub> in boiling
toluene to yield the termetallic complexes (CO)<sub>5</sub>Mo<i>M</i>(μ<sub>2</sub>-O<sup><i>t</i></sup>Bu)<sub>3</sub>Ce(O<sup><i>t</i></sup>Bu)<sub>3</sub> (<i>M</i> = Ge (<b>11</b>), Sn (<b>12</b>)). The new
compounds were characterized by comprehensive spectral studies, mass
spectroscopy, and single crystal X-ray diffraction analysis
Novel Air-Stable and Volatile Bis(pyridylalkenolato)palladium(II) and -platinum(II) Derivatives
Six novel homoleptic palladium(II) and platinum(II) complexes
of
donor-substituted alkenol ligands [PyCHC(R)OH; Py = pyridine, R =
CH<sub>3</sub>, CF<sub>3</sub>, C<sub>2</sub>F<sub>5</sub>, C<sub>3</sub>F<sub>7</sub>] of the general formula M[PyCHC(R)O]<sub>2</sub> (M = Pd, Pt) were synthesized by reacting the deprotonated ligands
with PdCl<sub>2</sub> and K<sub>2</sub>PtCl<sub>4</sub>, respectively.
Molecular structures, revealed by single-crystal X-ray diffraction
analyses, showed a square-planar arrangement of ligands around palladium
and platinum centers, with the pyridine-ring nitrogen atoms situated
in a mutually <i>trans</i> position. The monomeric nature
of the compounds in the solution state was confirmed by multinuclear
(<sup>1</sup>H, <sup>13</sup>C, and <sup>19</sup>F) NMR spectroscopy.
Thermal decomposition profiles recorded under a nitrogen atmosphere
suggested their potential as volatile precursors to palladium and
platinum materials. The volatility was increased upon elongation of
the perfluoroalkyl chain, which suppressed the intermolecular interactions,
as is evident in crystal packings. The volatility of these compounds
was attributed to bidentate chelation of the alkenol units and cooperativity
among the electron-back-donating nitrogen atom and interplay of electron-withdrawing
C<sub><i>x</i></sub>F<sub><i>y</i></sub> groups,
resulting in an effective steric shielding of the metal atoms