Scheme 11 RCAM/Lindlar hydrogenation approach to latrunculin A, 43, involving enyne–yne
coupling
Scheme 12 Ring-closing olefin metathesis (RCM)
¢
¢
Fig. 2 Selected metal alkylidene complexes that have been employed in RCM to 12- through
16-membered macrocyclic lactones
Synthesis of 12- to 16-Membered-Ring Lactones
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