Trimethylsilyl-ynones

Utimoto et al. [145] reported a procedure for the synthesis of macrocyclic ynones by intramolecular acylation of )-(trimethylsilyl)ethynylalkanoyl chlorides in the presence of Lewis acid. For example, in the synthesis of f — )-muscone 216), cyclization of alkyne acid chloride 238 gave the macrocycle 239 in 52% yield, which was hydrogenated to f — )-muscone (Scheme 80). 

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