| Abstract
| - Catalytic enantioselective 1,4-additions and tandem 1,4-addition−aldol reactions of dialkylzincreagents to cyclopentene-3,5-dione monoacetals in the presence of an in situ generated Cu(OTf)2/chiral phosphoramidite catalyst result in highly functionalized cyclopentane building blocks withee's up to 97%. A new synthesis of cyclopentene-3,5-dione monoacetals is presented as well as itsuse in a tandem 1,4-addition−aldol protocol for the catalytic asymmetric total synthesis of (−)-PGE1 methyl ester. This synthesis represents a new approach to this class of natural products. Byusing only 3 mol % of an enantiomerically pure catalyst in the key step, the absolute configurationsat three stereocenters of the basic structure of the PGE1 are established at once.
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