The reductions of 2-naphthaldehyde, (3), 9,90-spirobi-(9H-fluorene)-2-carboxaldehyde, (2), and 2-fluorenecarboxaldehyde, (4), have been studied in N,N-dimethylformamide (DMF) and acetonitrile. Putative spiroconjugation was the source of interest in 2 and its formal potential for the neutral/radical anion couple and the rate constant for dimerization of the radical anions were compared with the same quantities for 3 and 4. In DMF the range of formal potentials for 2–4 is only 100 mV and the rate constants for the three aldehydes differ by a factor of two. These small differences are consistent with insignificant spiroconjugative effects. The effect of added water on the dimerization rate constant for the radical anions of 3 has been interpreted in terms of reversible dimerization to a dimer dianion followed by irreversible protonation of the dianion by water.

Comparative studies of the reduction of 2-naphthaldehyde, 9,9'-spirobi-(9H-fluorene)-2-carboxaldehyde and 2-fluorenecarboxaldehyde in nonaqueous solvents

FIORAVANTI, GIULIA;
2005

Abstract

The reductions of 2-naphthaldehyde, (3), 9,90-spirobi-(9H-fluorene)-2-carboxaldehyde, (2), and 2-fluorenecarboxaldehyde, (4), have been studied in N,N-dimethylformamide (DMF) and acetonitrile. Putative spiroconjugation was the source of interest in 2 and its formal potential for the neutral/radical anion couple and the rate constant for dimerization of the radical anions were compared with the same quantities for 3 and 4. In DMF the range of formal potentials for 2–4 is only 100 mV and the rate constants for the three aldehydes differ by a factor of two. These small differences are consistent with insignificant spiroconjugative effects. The effect of added water on the dimerization rate constant for the radical anions of 3 has been interpreted in terms of reversible dimerization to a dimer dianion followed by irreversible protonation of the dianion by water.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11697/12518
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 5
  • ???jsp.display-item.citation.isi??? 4
social impact