Cicaprost synthesis

We have developed asymmetric syntheses of isocarbacyclin [3] (Scheme 1.3.2) and cicaprost [4] (Scheme 1.3.3) featuring a Cu-mediated allylic alkylation of an allyl sulfoximine [5-7] and a Ni-catalyzed cross-coupling reaction of a vinyl sulf-oximine [8-10], respectively, transformations that were both developed in our laboratories. The facile synthesis of an allyl sulfoximine by the addition-elimination-isomerization route aroused interest in the synthesis of sulfonimidoyl-sub-stituted aiiyititanium complexes of types 1 and 2 (Fig. 1.3.2) and their application as chiral heteroatom-substituted allyl transfer reagents [11]. 

Scheme 1.3.3 Asymmetric synthesis of cicaprost by the vinyl sulfoximine route.

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