en
Scientific article
Open access
English

Neutral, Radical [CpNi(dithiolene)] Complexes with Flexible, Nonplanar Seven-Membered Rings: [CpNi{S2C2S2(CH2)2X}] (X = CH2, CF2, C=CH2, S, C=O)

Published inEuropean journal of inorganic chemistry, vol. 2006, no. 24, p. 5012-5021
Publication date2006
Abstract

Neutral, radical [CpNi(dithiolene)] complexes fused with seven-membered rings, formulated as [CpNi{S2C2S2(CH2)2X}] (X = CH2, CF2, C=CH2, S), have been synthesized in 30-60 % yields from the reactions of nickelocene with the corresponding neutral, square-planar, (dithiolene)nickel complexes [Ni{S2C2S2(CH2)2X}2]. [CpNi{S2C2S2(CH2)2X}] (X = C=O) was prepared from nickelocene and [1,3]dithiolo[4,5-b][1,4]dithiepine-2,6-dione under thermal or photochemical conditions. All complexes exhibit reversible oxidation and reduction waves to the cation and anion form, respectively. The terminal groups (X) in the seven-membered ring shift their redox potentials to anodic potentials in the following order: CF2 > C=O > S > C=CH2 > CH2. The singlet EPR responses of [CpNi{S2C2S2(CH2)2(X)}] appear at g 2.0514-2.0529 in dichloromethane solution at room temperature. An NIR absorption is observed at max 798-848 nm ( 1700-2400 M-1 cm-1) in dichloromethane solution. The X-ray structures of the five complexes show two-legged piano-stool geometries around the central nickel atom (formally NiIII) and strong distortions from planarity of the seven-membered C2S2(CH2)2X rings. In the solid state, those radical (S = 1/2) species adopt either one-dimensional alternating chain-like motifs (X = CH2, C=CH2, S) or dimeric entities characterized by a singlet-triplet magnetic behavior (X = CF2, C=O).

Keywords
  • Nickel
  • S ligands
  • Radicals
  • Metallacycles
  • Magnetic properties
Research group
Citation (ISO format)
NOMURA, Mitsushiro et al. Neutral, Radical [CpNi(dithiolene)] Complexes with Flexible, Nonplanar Seven-Membered Rings: [CpNi{S2C2S2(CH2)2X}] (X = CH2, CF2, C=CH2, S, C=O). In: European journal of inorganic chemistry, 2006, vol. 2006, n° 24, p. 5012–5021. doi: 10.1002/ejic.200600649
Main files (1)
Article (Published version)
accessLevelPublic
Identifiers
ISSN of the journal1434-1948
651views
381downloads

Technical informations

Creation10/02/2009 3:19:10 PM
First validation10/02/2009 3:19:10 PM
Update time03/14/2023 3:15:45 PM
Status update03/14/2023 3:15:45 PM
Last indexation01/15/2024 7:04:18 PM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack