Circular dichroism spectroscopy of 2‐aminotetralins

Abstract

AbstractThe circular dichroism (CD) spectra of a series of oxygenated 2‐(dipropylamino)tetralin derivatives are reported. On the basis of known absolute configurations and conformational preferences of the compounds, the validity of published correlations between the sign of the 1Lb Cotton effect and the three‐dimensional structure was examined. Contrary to predictions, substitution in position 6 or 7 of the tetralin moiety did not change the sign of the 1Lb Cotton effect. An unexpected sign inversion was, however, observed in some of the compounds containing methyl substituents in the nonaromatic ring. The occurrence of this inversion was not correlated with a change in conformational behaviour and varied depending on the position and nature of the aromatic substituent. No correlations were obvious between the sign of the 1Lb Cotton effect and the absolute configuration and conformational preferences of the compounds. Therefore, at present, CD spectroscopy does not appear to be useful in assignments of the absolute configurations of 2‐(dipropylamino)tetralin derivatives. © 1995 Wiley‐Liss, Inc.