Synthesis of B/C trans-Fused Morphine Structures. VI. Mass Spectrum, Optical Rotatory Dispersion and Circular Dichroism of B/C trans-Morphine Derivatives

Abstract

Mass, optical rotatory dispersion (ORD) and circular dichroism (CD) spectra of the B/C trans-morphine derivatives have been studied in comparison with the natural (B/C cis) isomers. A characteristic difference between isomers epimeric at C₁₄ was found in mass spectrum in accord with the reported observation for the cis-and trans-morphinan derivatives. The stereochemistry of C₅ of trans-dihydrocodeinone (V) was established by ORD study and its conversion to trans-dihydrocodeine (VI) by NaBH₄ reduction.