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5-CYCLOHEXADECEN-1-ONE is commercially available as a 40 : 60 mixture of its (Z)- and (E)-isomers. It is a colorless liquid with an intense musk odor.
A three-step synthesis starts from cyclododecanone. Reaction with chlorine gives 2-chlorocyclododecanone, which is reacted with 2 mol of vinyl magnesium chloride to give 1,2-divinylcyclododecan-l-ol. This is finally converted into 5-cyclohexadecen-1-one by an oxy-Cope rearrangement.
5-Cyclohexadecen-l-one can be added to perfume compositions as a substitute for the natural macrocyclic ketone musks：

Musk TM-II (Soda Aromatic), Velvione® (Givaudan), Ambretone® (Takasago)