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The addition of lithium anion of (acetylmethylene)triphenylphosphorane to nonracemic sulfinimines was investigated. It was found that the addition proceeded with good diastereoselectivity and further reaction of the formed sulfinimidophosphorane with several aldehydes afforded the β-sulfinamido substituted enones in good yields. The resultant enones were elaborated to the synthesis of alkaloid (+)-241D, to the formal total synthesis of (+)-preussin, and to the synthesis of aminocyclopentenol.

Synthesis of isochromanones and isoquinolones comprising a quaternary center with high diastereoselectivity was realized via a AuCl3 catalyzed tandem intramolecular exo-dig heterocyclization/enol isomerization/Claisen rearrangement sequence in excellent yields. The reaction is general and amenable for the synthesis of structurally diverse analogues.

Enantioselective formal synthesis of macrolactone palmerolide A, a polyketide marine natural product, is described. Key strategies in the synthesis include the oxidative furan ring-opening of a chiral furyl carbinol for the installation of the 1,4-dienol core and a Jung nonaldol-aldol reaction for the dienamide core.

The enantiospecific total synthesis of 14-membered macrolactone Sch 725674 was accomplished from tartaric acid. Key reactions in the synthesis include the Ley's dithiaketalization of an alkynone derived from the bis-Weinreb amide of tartaric acid, Boord olefination, and ring-closing metathesis of an acrylate ester.

[reaction: see text] Diels-Alder reactions of enantiomerically enriched 2H-azirine 3-phosphonates and dienes stereoselectively furnish optically pure, bicyclic aziridine adducts that on hydrogenation afford the first examples of enantiopure quaternary piperidine phosphonates.