Английская Википедия:Caprolactone

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Шаблон:Chembox ε-Caprolactone or simply caprolactone is a lactone (a cyclic ester) possessing a seven-membered ring. Its name is derived from caproic acid. This colorless liquid is miscible with most organic solvents and water. It was once produced on a large scale as a precursor to caprolactam.[1]

Production and uses

Caprolactone is prepared industrially by Baeyer-Villiger oxidation of cyclohexanone with peracetic acid.

Caprolactone is a monomer used in the production of highly specialised polymers. Ring-opening polymerization, for example, gives polycaprolactone.[1] Another polymer is polyglecaprone, used as suture material in surgery.[2]

Reactions

Although no longer economical, caprolactone was once produced as a precursor to caprolactam. Caprolactone is treated with ammonia at elevated temperatures to give the lactam:

(CH2)5CO2 + NH3 → (CH2)5C(O)NH + H2O

Carbonylation of caprolactone gives, after hydrolysis, pimelic acid. The lactone ring is easily opened with nucleophiles including alcohols and water to give polylactones and eventually the 6-hydroxyadipic acid.

Related compounds

Several other caprolactones are known, including α-, β-, γ-, and δ-caprolactones. All are chiral. (R)-γ-caprolactone is a component of floral scents and of the aromas of some fruits and vegetables,[3] and is also produced by the Khapra beetle as a pheromone.[4] δ-caprolactone is found in heated milk fat.[5]

An ether of caprolactone is used as a binder for AP/AN/Al rocket propellant HTCE: Hydroxy-Terminated Caprolactone Ether [6]

Safety

Caprolactone hydrolyses rapidly and the resulting hydroxycarboxylic acid displays unexceptional toxicity, as is common for the other hydroxycarboxylic acids.[7] It is known to cause severe eye irritation. Exposure may result in corneal injury.[8]

References

Шаблон:Reflist

Шаблон:Authority control

  1. 1,0 1,1 Шаблон:Cite encyclopedia
  2. Шаблон:Cite web
  3. Шаблон:Cite journal
  4. Шаблон:Cite journal
  5. Шаблон:Cite journal
  6. HTCE
  7. Шаблон:Cite encyclopedia
  8. Ошибка цитирования Неверный тег <ref>; для сносок OECD не указан текст