jo802241x_si_001.pdf (1.03 MB)

Nucleophilicities of the Anions of Arylacetonitriles and Arylpropionitriles in Dimethyl Sulfoxide

Download (1.03 MB)
journal contribution
posted on 02.01.2009 by Oliver Kaumanns, Roland Appel, Tadeusz Lemek, Florian Seeliger, Herbert Mayr
The rates of the reactions of the colored para-substituted phenylacetonitrile anions 1ac and the phenylpropionitrile anions 2ac with Michael acceptors (3au) were determined by UV−vis spectroscopy in DMSO at 20 °C. The reactions follow second-order kinetics, and the corresponding rate constants k2 obey the linear-free-energy relationship log k2(20 °C) = s(N + E), from which the nucleophile-specific parameters N and s of the carbanions 1ac and 2ac have been derived. With nucleophilicity parameters from 19 < N < 29, they are among the most reactive nucleophiles which we have so far parametrized. In DMSO, the nucleophilicity of the tert-butoxide anion is comparable to that of the p-cyanophenylacetonitrile anion 1b.

History

Exports