The stereoselective access to (E)-alkene 25 was achieved by a semi-reduction
method, which employed a ruthenium-catalyzed trans-hydrosilylation followed by
a protodesilylation [25] (Scheme 6).
2.3 13-Membered Macrocyclic Lactones
2.3.1 PGE 2 -1,15-lactone
The intrinsically acid- and base-labile β-hydroxy ketone moiety rendered the
13-membered prostaglandin PGE 2 -1,15-lactone 28 as a probe for the applicability
of the RCAM/Lindlar reduction strategy using catalyst 4. The key transformation
Scheme 5 Synthesis of lactimidomycin, 23 by RCAM strategy involving enyne–yne coupling
Scheme 6 Post-RCAM entry to E,Z-configured 1,3-diene 25
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M. Cordes and M. Kalesse
method, which employed a ruthenium-catalyzed trans-hydrosilylation followed by
a protodesilylation [25] (Scheme 6).
2.3 13-Membered Macrocyclic Lactones
2.3.1 PGE 2 -1,15-lactone
The intrinsically acid- and base-labile β-hydroxy ketone moiety rendered the
13-membered prostaglandin PGE 2 -1,15-lactone 28 as a probe for the applicability
of the RCAM/Lindlar reduction strategy using catalyst 4. The key transformation
Scheme 5 Synthesis of lactimidomycin, 23 by RCAM strategy involving enyne–yne coupling
Scheme 6 Post-RCAM entry to E,Z-configured 1,3-diene 25
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M. Cordes and M. Kalesse