12 research outputs found
Nickel(II) and Palladium(II) Thiaethyneporphyrins. Intramolecular Metal(II)âη<sup>2</sup>-CC Interaction inside a Porphyrinoid Frame
3,18-Diphenyl-8,13-di-<i>p</i>-tolyl-20-thiaethyneporphyrin
([18]ÂthiatriphyrinÂ(4.1.1)), which formally contains an C1âC2
ethyne moiety instead of pyrrole embedded in the macrocyclic framework
of 21-thiaporphyrin, was obtained in a modification of the â3
+ 1â approach using the ethyne analogue of tripyrrane (1,4-diphenyl-1,4-di(pyrrol-2-yl)but-2-yne)
and 2,5-bisÂ(<i>p</i>-tolylhydroxymethyl)Âthiophene. The spectroscopic and structural
properties of 20-thiaethyneporphyrin reflect its macrocyclic aromaticity,
revealing a combination of the acetylene (â„CâCîŒCâCâ€)
and cumulene (>Cî»Cî»Cî»C<) character of the
C18âC1âC2âC3 linker. The magnetic manifestations
of aromaticity and antiaromaticity of thiaethyneporphyrin and its
two-electron-oxidized derivative were observed using <sup>1</sup>H
NMR spectroscopy and were confirmed by density functional theory calculations
involving chemical shifts and nucleus-independent chemical shift analysis.
Protonation of 20-thiaethyneporphyrin yielded a nonaromatic tautomer
of <i>iso</i>-20-thiaethyneporphyrin, locating the saturated
meso carbon adjacent to thiophene. Insertion of palladiumÂ(II) and
nickelÂ(II) into 20-thiaethyneporphyrin afforded planar palladiumÂ(II)
thiaethyneporphyrin and low-spin diamagnetic nickelÂ(II) 20-thiaethyneporphyrin
as determined by X-ray crystallography. 20-Thiaethyneporphyrin acts
as a dianionic ligand that coordinates through the two nitrogen and
one sulfur donors. MetalÂ(II) ions are uniquely exposed to form an
intramolecular metalÂ(II)âη<sup>2</sup>-CC bond, whereas
the organometallic fragment is coplanar with the whole macrocycle.
Coordination of pyridine converts diamagnetic nickelÂ(II) thiaethyneporphyrin
into its paramagnetic counterpart as determined by <sup>1</sup>H NMR
NMR Investigation of ÎČ-Substituted High-Spin and Low-Spin Iron(III) Tetraphenylporphyrins
Palladium Vacataporphyrin Reveals Conformational Rearrangements Involving HĂŒckel and Möbius Macrocyclic Topologies
Copper(II) Thiaethyneporphyrin and Copper(II) 21-Phosphoryl Nâconfused Porphyrin Hybrids. Intramolecular Copper(II)âCarbon Interaction Inside of a Porphyrinoid Surrounding
Stabilization of unusual organocopperÂ(II) species via
the very efficient protection of the copperÂ(II)âcarbon bond
has been achieved encapsulating the copperÂ(II) center in the coordination
core of suitably constructed carbaporphyrinoids. CopperÂ(II) was inserted
into hybrid N-confused porphyrins which contain 21-diphenylphosphoryl-,
21-diphenylthiophosphoryl-, or 21-phosphinodithioic substituents or
into 20-thiaethyneporphyrin, an aromatic porphyrinoid, which combines
two structural motifs of 21-thiaporphyrin and ethyne. Two distinctly
different types of the copperÂ(II)âcarbon bond have been detected.
CopperÂ(II) hybrid N-confused porphyrins reveal the η<sup>1</sup>-CÂ(21) side-on coordination. The unprecedented equatorial metalÂ(II)···η<sup>2</sup>-CC interaction has been trapped in a copperÂ(II) thiaethyneporphyrin
surrounding
Copper(II) Thiaethyneporphyrin and Copper(II) 21-Phosphoryl Nâconfused Porphyrin Hybrids. Intramolecular Copper(II)âCarbon Interaction Inside of a Porphyrinoid Surrounding
Stabilization of unusual organocopperÂ(II) species via
the very efficient protection of the copperÂ(II)âcarbon bond
has been achieved encapsulating the copperÂ(II) center in the coordination
core of suitably constructed carbaporphyrinoids. CopperÂ(II) was inserted
into hybrid N-confused porphyrins which contain 21-diphenylphosphoryl-,
21-diphenylthiophosphoryl-, or 21-phosphinodithioic substituents or
into 20-thiaethyneporphyrin, an aromatic porphyrinoid, which combines
two structural motifs of 21-thiaporphyrin and ethyne. Two distinctly
different types of the copperÂ(II)âcarbon bond have been detected.
CopperÂ(II) hybrid N-confused porphyrins reveal the η<sup>1</sup>-CÂ(21) side-on coordination. The unprecedented equatorial metalÂ(II)···η<sup>2</sup>-CC interaction has been trapped in a copperÂ(II) thiaethyneporphyrin
surrounding
Nickel(II) and Palladium(II) Thiaethyneporphyrins. Intramolecular Metal(II)âη<sup>2</sup>-CC Interaction inside a Porphyrinoid Frame
3,18-Diphenyl-8,13-di-<i>p</i>-tolyl-20-thiaethyneporphyrin
([18]ÂthiatriphyrinÂ(4.1.1)), which formally contains an C1âC2
ethyne moiety instead of pyrrole embedded in the macrocyclic framework
of 21-thiaporphyrin, was obtained in a modification of the â3
+ 1â approach using the ethyne analogue of tripyrrane (1,4-diphenyl-1,4-di(pyrrol-2-yl)but-2-yne)
and 2,5-bisÂ(<i>p</i>-tolylhydroxymethyl)Âthiophene. The spectroscopic and structural
properties of 20-thiaethyneporphyrin reflect its macrocyclic aromaticity,
revealing a combination of the acetylene (â„CâCîŒCâCâ€)
and cumulene (>Cî»Cî»Cî»C<) character of the
C18âC1âC2âC3 linker. The magnetic manifestations
of aromaticity and antiaromaticity of thiaethyneporphyrin and its
two-electron-oxidized derivative were observed using <sup>1</sup>H
NMR spectroscopy and were confirmed by density functional theory calculations
involving chemical shifts and nucleus-independent chemical shift analysis.
Protonation of 20-thiaethyneporphyrin yielded a nonaromatic tautomer
of <i>iso</i>-20-thiaethyneporphyrin, locating the saturated
meso carbon adjacent to thiophene. Insertion of palladiumÂ(II) and
nickelÂ(II) into 20-thiaethyneporphyrin afforded planar palladiumÂ(II)
thiaethyneporphyrin and low-spin diamagnetic nickelÂ(II) 20-thiaethyneporphyrin
as determined by X-ray crystallography. 20-Thiaethyneporphyrin acts
as a dianionic ligand that coordinates through the two nitrogen and
one sulfur donors. MetalÂ(II) ions are uniquely exposed to form an
intramolecular metalÂ(II)âη<sup>2</sup>-CC bond, whereas
the organometallic fragment is coplanar with the whole macrocycle.
Coordination of pyridine converts diamagnetic nickelÂ(II) thiaethyneporphyrin
into its paramagnetic counterpart as determined by <sup>1</sup>H NMR