Synthesis, stereochemistry, and chiroptical spectra of cyclopropyl lactones and thionolactones

Article abstract of DOI:10.1016/0957-4166(96)00419-3

Several optically active substituted 3-oxabicyclo[3.1.0]hexan-2-ones and their thiocarbonyl analogues were synthesized, and their circular dichroism spectra are reported. It was found that the n-π* Cotton effect sign is determined by the helicity of an inherently chiral chromophore formed by the lactone or thiolactone group and the cyclopropyl moiety. The π-π* Cotton effect of thiocarbonyl compounds shows opposite sign to that observed for the lowest energy transition. The crystal structures of two compounds were solved to establish their molecular geometries. Copyright (C) Elsevier Science Ltd.