ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Radical Ions, 70. The Effect of Phosphorus Substituents on the Cyclovoltammetric Reduction of Aromatic π-SystemsThe half-wave reduction potentials of 23 phosphororganic compounds Rπ(PR2)n, Rπ(P⊕ R3)n, and Rπ(PYR2)n, with π-systems Rπ = benzene, biphenyl, naphthalene, thiophene, styrene, phenylacetylene, ferrocene, and phosphorus substituents R=CH3, C6H5 as well as Y=O, S, Se, NR and n = 1,2 are determined by cyclic voltammetry in DMF under aprotic measurement conditions. Statistical analysis within a π-perturbation model and comparison with the CV data of other 1,4-disubstituted benzene derivatives establishes the following sequence of increasing acceptor effect of the substituents P(CH3)2 ≪ Si(CH3)3 〈 P(C6H5)2 〈 PO(CH3)2 〈 PS(CH3)2, ≍ P(NR)(CH3)2 ≍ PSe(CH3)2 ≪ CN 〈 P⊕ (CH3)3 ≪ BR2 〈 P⊕ (C6H5)3 ≪ NO2.
Notes:
Die Halbstufen-Reduktionspotentiale von 23 phosphororganischen Verbindungen Rπ(PR2)n, Rπ(P⊕ R3)n und Rπ(PYR2)n mit π-Systemen Rπ = Benzol, Biphenyl, Naphthalin, Thiophen, Styrol, Phenylacetylen, Ferrocen und Phosphor-Substituenten R=CH3, C6H5 sowie Y=O, S, Se, NR und n = 1,2 werden unter aprotischen Meßbedingungen in DMF cyclovoltammetrisch bestimmt. Statistische Auswertung innerhalb eines π-Störungsmodells und Vergleich mit den CV-Daten weiterer 1,4-disubstituierter Benzol-Derivate ergibt als Reihenfolge zunehmender Akzeptorwirkung des Substituenten P(CH3)2 ≪ Si(CH3)3 〈 P(C6H5)2 〈 PO(CH3)2 〈 PS(CH3)2 ≍ P(NR)(CH3)2 ≍ PSe(CH3)2 ≪ CN 〈 P⊕ (CH3)3 ≪ BR2 〈 P⊕ (C6H5)3 ≪ NO2.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19861191220
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