Synthesis and circular dichroism of some bicyclic compounds related to camphor with chirality due to deuterium substitution

Abstract

Deuteriated optically active fenchocamphorquinone (1a), apocamphoric anhydride (2a), apocamphorimide (3a), and N-nitrosoapocamphidine (4a) of known absolute configuration were prepared and their absorption and circular dichroism spectra were measured. The deuterium atom was introduced into the asymmetric 1-position by a method based on catalytic decarbonylation of the corresponding deuterioaldehyde or, alternatively, by decarboxylation of deuterio-carboxylic acid. The contributions of the C–D and C–CH₃ bonds to the chiroptical activity were compared.