Journalartikel

Jahr der Veröffentlichung: 1999

Seiten: 2915-2927

Zeitschrift: European Journal of Organic Chemistry

Bandnummer: 1999

Heftnummer: 11

ISSN: 1434-193X

Verlag: Wiley

Abstract: 
2,4-Disubstituted pentanes are molecules which adopt essentially only two conformations. Substituents have been varied in order to find those which lead to a strong preference of the conformer equilibrium. Studying 2-substituted 4-methylpentanes 3 and 4-benzyloxypentanes 12, it has been shown that substituent effects on the conformer equilibria are not additive, as would be expected on the grounds of steric effects alone. Rather, interactions between polar groups reinforce the bias of the conformer equilibria. When applied to 2,4-disubstituted pentanes, substituents such as chloro or phthalimido shift the conformer equilibrium to the side of the gg conformer with preferences exceeding 90%.