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The Cobalt cyclo-P₄ Sandwich Complex and Its Role in the Formation of Polyphosphorus Compounds.

ABSTRACT: A synthetic approach to the sandwich complex [Cp'''Co(?⁴ -P₄ )] (2) containing a cyclo-P₄ ligand as an end-deck was developed. Complex 2 is the missing homologue in the series of first-row cyclo-P_n sandwich complexes, and shows a unique tendency to dimerize in solution to form two isomeric P₈ complexes [(Cp'''Co)₂ (?,?⁴ :?² :?¹ -P₈ )] (3 and 4). Reactivity studies indicate that 2 and 3 react with further [Cp'''Co] fragments to give [(Cp'''Co)₂ (?,?² :?² -P₂ )₂ ] (5) and [(Cp'''Co)₃ P₈ ] (6), respectively. Furthermore, complexes 2, 3, and 4 thermally decompose forming 5, 6, and the P₁₂ complex [(Cp'''Co)₃ P₁₂ ] (7). DFT calculations on the P₄ activation process suggest a ?³ -P₄ Co complex as the key intermediate in the synthesis of 2 as well as in the formation of larger polyphosphorus complexes via a unique oligomerization pathway.

SUBMITTER: Dielmann F

PROVIDER: S-EPMC5299486 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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The Cobalt cyclo-P4 Sandwich Complex and Its Role in the Formation of Polyphosphorus Compounds.

Dielmann Fabian F Timoshkin Alexey A Piesch Martin M Balázs Gábor G Scheer Manfred M

Angewandte Chemie (International ed. in English) 20170112 6

A synthetic approach to the sandwich complex [Cp'''Co(η4 -P4 )] (2) containing a cyclo-P4 ligand as an end-deck was developed. Complex 2 is the missing homologue in the series of first-row cyclo-Pn sandwich complexes, and shows a unique tendency to dimerize in solution to form two isomeric P8 complexes [(Cp'''Co)2 (μ,η4 :η2 :η1 -P8 )] (3 and 4). Reactivity studies indicate that 2 and 3 r ...[more]

PMID: 28078794

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