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The Diels-Alder (DA) reaction is perhaps the most powerful method for the stereocontrolled synthesis of complex molecules. 1 In a single step it produces six-membered carbocycles and heterocycles with from one to as many as four stereocenters. Among the many advances with this reaction, 2-4 of particular significance are the numerous chiral Lewis acid-catalyzed cycloadditions. 5, 6 A large percentage of successful enantioselective DA reactions reported involve the use of a cyclic diene, most commonly cyclopentadiene. 5b Of the acyclic dienes reported, most are monosubstituted butadienes. 7 Surprisingly, enantioselective DA reactions of multiply heteroatom-substituted dienes, such as Danishefsky’s diene, 8 appear to not have been reported despite their tremendous usefulness in complex molecule synthesis. 9 In connection with our interest in the chemistry of 1-amino-3-siloxy-1, 3-butadienes, 10 we have …