OXIDATION OF HOMOCHIRAL KETALS BY RHENIUM(VII) OXIDE .5.

[摘要] 2-Hydroxyethyl enol ethers react with Re2O7 to produce 2-hydroxyketals. Where homochral starting enol ethers are employed, greater than 99:1 diastereoselectivities are obtained. The stereocontrol is rationalized by involving a transition state that approximates the geometry of a metallaoxetane. Finally, homochiral ketals are themselves oxidized to provide 2-hydroxyketals with high diastereoselectivity.

[发布日期] 1992-12-15