Limits...
The chemistry of cationic polyphosphorus cages--syntheses, structure and reactivity.

Holthausen MH, Weigand JJ - Chem Soc Rev (2014)

Bottom Line: The aim of this review is to provide a comprehensive view of the chemistry of cationic polyphosphorus cages.The synthetic protocols established for their preparation, which are all based on the functionalization of P4, and their intriguing follow-up chemistry are highlighted.In addition, this review intends to foster the interest of the inorganic, organic, catalytic and material oriented chemical communities in the versatile field of polyphosphorus cage compounds.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, University of Toronto, Toronto, Canada. m.holthausen@utoronto.ca.

ABSTRACT
The aim of this review is to provide a comprehensive view of the chemistry of cationic polyphosphorus cages. The synthetic protocols established for their preparation, which are all based on the functionalization of P4, and their intriguing follow-up chemistry are highlighted. In addition, this review intends to foster the interest of the inorganic, organic, catalytic and material oriented chemical communities in the versatile field of polyphosphorus cage compounds. In the long term, this is envisioned to contribute to the development of new synthetic procedures for the functionalization of P4 and its transformation into (organo-)phosphorus compounds and materials of added value.

No MeSH data available.


Related in: MedlinePlus

Stepwise insertion of zwitterionic silylene 39 into P–P bonds of P4 yielding SiP4-cage compound 40 and Si2P4-cage compound 41.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4288811&req=5

sch11: Stepwise insertion of zwitterionic silylene 39 into P–P bonds of P4 yielding SiP4-cage compound 40 and Si2P4-cage compound 41.

Mentions: The 31P NMR spectra of cage cations 36+ show A2M2X or A2MX2 spin systems in accordance with their C2V symmetry and are comparable to those observed for the P5X2+ cages 26a–c+ (Fig. 11). The observation of two different spin systems for R2P5+-cages of type 36+ may be explained in terms of different steric and electronic influences of the alkyl- or aryl-substituent R. In the series of alkyl-substituted R2P5+-cages (36a+ to 36d+) the resonances of the phosphonium P atoms are shifted to higher field and the resonances of the adjacent P atoms are shifted to lower field. This can be explained in terms of a combination of a-effect and γ-effect (vide infra).46,47 The resonances of the tetra-coordinated P atoms in aryl-substituted cations 36e–h+ are shifted to higher field compared to those of the corresponding P atoms in cages 36a–d+. This is due to a positive mesomeric effect, namely the donation of π-electron density from the aryl substituents to the lobes of the anti-bonding σ*(P–P) orbitals at the phosphonium moiety.47a Some main group centered, predominantly electrophilic ambiphiles react with P4via multiple insertions into P–P bonds of the P4 tetrahedron. This is exemplified by SiP4-cage compound 40, which is obtained by the reaction of P4 with zwitterionic silylene 39. This compound reacts with a second equivalent of 39 to give the Si2P4-cage compound 41 (Scheme 11).14 The second insertion takes place at a P–P bond opposing the initially inserted main group element. The related product 4 was obtained by the reaction of P4 with a low valent Al(i) species (Fig. 2).13


The chemistry of cationic polyphosphorus cages--syntheses, structure and reactivity.

Holthausen MH, Weigand JJ - Chem Soc Rev (2014)

Stepwise insertion of zwitterionic silylene 39 into P–P bonds of P4 yielding SiP4-cage compound 40 and Si2P4-cage compound 41.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4288811&req=5

sch11: Stepwise insertion of zwitterionic silylene 39 into P–P bonds of P4 yielding SiP4-cage compound 40 and Si2P4-cage compound 41.
Mentions: The 31P NMR spectra of cage cations 36+ show A2M2X or A2MX2 spin systems in accordance with their C2V symmetry and are comparable to those observed for the P5X2+ cages 26a–c+ (Fig. 11). The observation of two different spin systems for R2P5+-cages of type 36+ may be explained in terms of different steric and electronic influences of the alkyl- or aryl-substituent R. In the series of alkyl-substituted R2P5+-cages (36a+ to 36d+) the resonances of the phosphonium P atoms are shifted to higher field and the resonances of the adjacent P atoms are shifted to lower field. This can be explained in terms of a combination of a-effect and γ-effect (vide infra).46,47 The resonances of the tetra-coordinated P atoms in aryl-substituted cations 36e–h+ are shifted to higher field compared to those of the corresponding P atoms in cages 36a–d+. This is due to a positive mesomeric effect, namely the donation of π-electron density from the aryl substituents to the lobes of the anti-bonding σ*(P–P) orbitals at the phosphonium moiety.47a Some main group centered, predominantly electrophilic ambiphiles react with P4via multiple insertions into P–P bonds of the P4 tetrahedron. This is exemplified by SiP4-cage compound 40, which is obtained by the reaction of P4 with zwitterionic silylene 39. This compound reacts with a second equivalent of 39 to give the Si2P4-cage compound 41 (Scheme 11).14 The second insertion takes place at a P–P bond opposing the initially inserted main group element. The related product 4 was obtained by the reaction of P4 with a low valent Al(i) species (Fig. 2).13

Bottom Line: The aim of this review is to provide a comprehensive view of the chemistry of cationic polyphosphorus cages.The synthetic protocols established for their preparation, which are all based on the functionalization of P4, and their intriguing follow-up chemistry are highlighted.In addition, this review intends to foster the interest of the inorganic, organic, catalytic and material oriented chemical communities in the versatile field of polyphosphorus cage compounds.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, University of Toronto, Toronto, Canada. m.holthausen@utoronto.ca.

ABSTRACT
The aim of this review is to provide a comprehensive view of the chemistry of cationic polyphosphorus cages. The synthetic protocols established for their preparation, which are all based on the functionalization of P4, and their intriguing follow-up chemistry are highlighted. In addition, this review intends to foster the interest of the inorganic, organic, catalytic and material oriented chemical communities in the versatile field of polyphosphorus cage compounds. In the long term, this is envisioned to contribute to the development of new synthetic procedures for the functionalization of P4 and its transformation into (organo-)phosphorus compounds and materials of added value.

No MeSH data available.


Related in: MedlinePlus