Stereocontrolled synthesis of exocyclic olefins using arene tricarbonyl chromium complex-catalyzed hydrogenation. II. A catalytic asymmetric synthesis of an anthracycline intermediate.
MANGANESE-MEDIATED ALLYL ADDITION TO ENOLIZABLE ALDEHYDE AND KETONES. AN APPROACH FOR INTRODUCTION OF ACETONYL SIDE CHAIN AT C(9) OF ANTHRACYCLINE ANTIBIOTICS
作者:Tamejiro Hiyama、Miwa Sawahara、Yukari Kusano
DOI:10.1246/cl.1985.611
日期:1985.5.5
Allyladdition to enolizable aldehyde and ketones is achieved efficiently with manganese reagents generated by the reaction of allyl bromide with MnCl2–LiAlH4 or Mn powder. The Wacker oxidation of the β-tetralone adducts gives an acetonyl moiety typical to an anti-tumor antibiotic, feudomycin.
method for the stereospecificsynthesis of exo-allylic alcohols with trisubstituents is described. Using this methodology in combination with Sharpless catalytic asymmetric epoxidation, an efficient synthesis of (R)-(-)-2-acetyl-5,8-dimethoxy-1,2,3,4- tetrahydro-2-naphthol (5), an important intermediate for the anthracycline synthesis, has been accomplished in 36% overall yield from 5,8-dimethoxy-2-tetralone