摘要：

The conjugate addition of the chiral, non-racemic alkoxy-enolates 5 and 6 to nitroolefins furnishes the hydroxynitroesters 7–13 , which are catalytically hydrogenated to give the lactams 14–18 . The configuration of adduct 7 from nitroethylene was elucidated by NMR. analysis of the acetal 20 derived from 7 . The assignment establishes that the reaction follows the stereochemical rule of attack depicted in 21 and previously deduced for other electrophiles, i.e. formation of erythro -products of type 3b and 4b . No stereocontrol was found at the newly formed chiral centers in α- and β-position to the NO 2 group of 8–12 .

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