714960-49-3Relevant academic research and scientific papers
Synthesis and electrochemistry of iron-pyrylium complexes
Shaw, Michael J.,Afridi, Seema J.,Light, Susan L.,Mertz, Jaime N.,Ripperda, Shane E.
, p. 2778 - 2783 (2008/10/09)
The syntheses and characterization of three cationic iron-pyrylium complexes (2+, [2-OMe-3-Fp-5,6-Ph2(C5HO)] +; 3+, [2-OMe-3-Fp-6-Ph(C5H2O)] +; 4+, [2-OMe-3-Fp′-6-Ph (C5H 2O)]+) that result from the sequential addition of methyl propiolate and PhCΞCR (R = Ph, H) to FpBF4 (Fp = η5-C5H5(CO)2Fe) or Fp′PF6 (Fp′ = η5-(C5H 4Me)(CO)2Fe) are presented. The initially formed cationic Fp-methyl propiolate complex is shown to convert into a complicated mixture that includes the corresponding vinylidene and alkynyl complexes. The iron-pyrylium complexes have been characterized by 1H NMR and IR spectroscopy, elemental analysis, FAB-MS, electrochemical, and fiber-optic-IR and ESR spectroelectrochemical techniques. These metal-pyrylium complexes undergo electron transfer at the pyrylium ring rather than at the metal center. The subsequent chemistry of the neutral species 2·, 3·, and 4· is strongly influenced by the nature of the substituents on the ring. The sterically protected complex 2+ undergoes chemically and electrochemically reversible reductions. The complexes 3+ and 4 + undergo dimerization reactions after reduction presumably through the 4-position of the pyrylium ring.
