Cyclopentadecanone

Chemical properties

WHITE CRYSTALLINE POWDER

Chemical properties

Cyclopentadecanone is a musk fragrance found in the scent gland of the male civet cat.
A number of syntheses have been developed for its manufacture [260]. Among these, the so-called Story procedure is the only route that has the potential to make cyclopentadecanone available on a larger scale, but due to the handling of hydroperoxides, the process is difficult to manage.
The process starts from tricyclohexylidene triperoxide, which is obtained by oxidation of cyclohexanone with hydrogen peroxide. Pyrolysis leads to a mixture of 1,16-hexadecanolide and cyclopentadecane. The latter is oxidized by oxygen under boric acid catalysis to cyclopentadecanol, which is subsequently oxidized to cyclopentadecanone.
Due to the availability of long-chained aliphatic dicarboxylic acids by biotechnological processes, a Dieckmann condensation reaction may also possibly be a useful route to produce this macrocyclic ketone.
Cyclopentadecanone is used in fine fragrances：

Occurrence

Reported to be found in the scent glands of the Louisiana muskrat Ondatra zibethicus rivalicius (Guenther, 1949).

The Uses of Cyclopentadecanone

Cyclopentadecanone is the main odoriferous component of musk.

Preparation

By the cyclization of dinitriles in high dilution (Bedoukian. 1967).

Synthesis Reference(s)

Chemistry Letters, 7, p. 1283, 1978
The Journal of Organic Chemistry, 36, p. 3266, 1971 DOI: 10.1021/jo00821a003

Toxicity evaluation

Both the acute oral LD₅₀ value in rats and the acute dermal LD₅₀ value in rabbits exceeded 5 g/kg (Moreno. 1975). The acute ip LD₁₀₀ of cyclopentadecanone was not reached but was estimated to be >35mmol/kg for mice; an ip dose of 11-25 mmol/kg caused no deaths in 24 hr and one of 8-92 mmol/kg caused no deaths in 4 days (the length of the study). An oral dose of ≥45 mmol/kg caused no deaths in mice. Intense agitation accompanied by catatonia of the tail was caused by low doses of cyclopentadecanone; gross examination of the mice revealed no specific pathology but occasionally degenerative hepatitis, proximal tubular nephritis and, rarely, pancreatic necrosis were found following dosing with cycloalkanones (Caujolle & Caujolle, 1965).

Flammability and Explosibility

Non flammable

Metabolism

Ketones are not readily metabolized, although most of them probably undergo appreciable reduction to the corresponding secondary alcohols, which are excreted in the urine as glucuronic acid conjugates (Williams, 1959). Cyclopentadecanone was hydroxylated in cultures of four steroid-hydroxylating fungi (Calonectria decora, Rhizopus nigricans, Daedalea rufescens and Ophiobolus herpotrichus), but was not affected by Aspergillus ochraceus. Initial attack occurred at the most remote carbon atom, with yields of up to 26% of 8-hydroxycyclopentadecanone, plus dihydroxy compounds and more polar products (Ashton, Bailey & Jones, 1974).

Purification Methods

Subliming Exaltone is better than crystallising it from aqueous EtOH for purification. The semicarbazone has m 186-187o. [Stevens & Erickson J Am Chem Soc 64 146 1942, Mathur et al. J Chem Soc 3505 1963, Biens & Hess Helv Chim Acta 71 1704 1988, Beilstein 7 III 203, 7 IV 118.]