A practical synthesis of thebaine and oripavine has been developed from codeine and morphine, respectively. Attempts to use a codeinone intermediate gave poor yields; however, methylation of the potassium salt of codeine to give codeine methyl ether followed by oxidation with y-MnOz gave thebaine in 67% yield from codeine. Similarly, the potassium salt of the di-0-anion of morphine was selectively alkylated to give morphine 6-methyl ...
