摘要:
Bromination of endo-ethenotetrahydrothebaine derivatives having a pyrrolidine ring fused at the C-7-C-8 stop bond, namely 1'-substituted 4,5 alpha-epoxy-6 alpha,14-etheno-3,6-dimethoxy-17-methyl-2',5',7 beta,8 beta-tetrahydro-1'H-14 alpha-pyrrolo[3',4':7,8]morphinan-2',5'-diones, 1'-aryl-4,5 alpha-epoxy-6 alpha,14-etheno-3,6-dimethoxy-17-methyl-2',5',7 beta,8 beta-tetrahydro-1'H-14 alpha-pyrrolo[3',4':7,8]morphinans, and 4,5 alpha-epoxy-6 alpha,14-etheno-2'+/--hydroxy-3,6- dimethoxy-17-methyl-1'-phenyl-2',5',7 beta,8 beta-tetrahydro-1'H-14 alpha-pyrrolo[3',4':7,8]morpphinan-5'-one, with molecular bromine in formic acid smoothly afforded the corresponding 1-bromo derivatives. Iodination of 4,5 alpha-epoxy-6 alpha,14-etheno-3,6-dimethoxy-17-methyl-1'-phenyl-2',5',7 beta,8 beta-tetrahydro-1'H-14 alpha-pyrrolo[3',4':7,8]-4,5 alpha-epoxy-6 alpha,14-etheno-3,6-dimethoxy-17-methyl-1'-phenyl-2',5',7 beta,8 beta-tetrahydro-1'H-14 alpha-pyrrolo[3',4':7,8]-morphinan-2',5'-dione with iodine(I) chloride gave 4,5 alpha-epoxy-6 alpha,14-etheno-1-iodo-3,6-dimethoxy-17-methyl-1'-phenyl-2',5',7 beta,8 beta-tetrahydro-1'H-14 alpha-pyrrolo[3',4':7,8]morphinan-2',5'-dione. The resulting 1-halo derivatives were brought into the Heck reaction with acrylic acid esters to obtain 1-[(E)-2-(alkoxycarbonyl)ethenyl]-substituted compounds. Demethylation of the 6-methoxy group in 1-bromo-endo-ethenotetrahydrothebaines was accomplished using boron(III) bromide in chloroform.