Synthesis and Chiroptical Properties of Arylimines of Cholest-4-ene-3,6-dione

摘要

In the hope of generating a new class of materials with large opticalnrotations, various arylamines were condensed with cholest-4-ene-3,6-dione (2) tongive 3-arylimino steroids. These compounds possess moderately high specificnrotations ([α]D ∼300−800) and strong circular dichroism. One such derivative, 3-n(4-methoxyphenylimino)cholest-4-en-6-one (3), crystallizes as the (E)-imine andnupon dissolution undergoes mutarotation to an equilibrium mixture of (E)- andn(Z)-isomers with a half-life of approximately 1 h at room temperature, as judgednby both NMR spectroscopy and polarimetry.