Yuzu lactone

Using this catalyst system for ring-closing alkyne metathesis, Fiirstner successfully synthesized ambrettolide and yuzu lactone from alcohol 125. " " Treatment of diyne 126a with Mo(CO)6 (5 mol%) and /i-chlorophenol (1 equiv.) in chlorobenzene at 140 °C leads to cycloalkyne 127a in 69% yield. Subsequent Lindlar reduction proceeds smoothly in a stereoselective manner to afford ambrettolide. Similarly, 126b affords cycloalkyne 127b in 62% yield. From this compound, yuzu lactone has been synthesized (Scheme 45). " " ... 

The macrocyclic musks and fragrances, yuzu lactone (12) [28], ambrettolide (13) [28], and civetone (14) [29], which all contain a (Z)-configured aUcene, were chosen as early targets for application of an RCAM/Lindlar reduction strategy (Figure 7.2). In all cases, application of the Mortreux instant system was successful, and the desired (Z)-alkene isomers were obtained exclusively from hydrogenation [28, 29]. 

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