Preparation of .epsilon.-caprolactone

US4341709A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Willi Hofen · Rodenbach, DE
• Herbert Klenk · Hanau, DE
• Gerd Schreyer
• Otto Weiberg
• Helmut Waldmann · Leverkusen, DE
• Hermann Seifert · Bensberg, DE
• Karl-Hermann Reissinger
• Wolfgang Swodenk

Key dates

• Filing date: May 15, 1980
• Grant date: Jul 27, 1982
• Expiry date: May 15, 2000

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D315/00
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of .epsilon.-caprolactone comprising: PA1 (a) reacting cyclohexanone with a solution of perpropionic acid in an organic solvent at a molar ratio of cyclohexanone;perpropionic acid of about 1.1-5:1 at a temperature of about 10.degree. to 80.degree. C. to form a reaction mixture consisting essentially of .epsilon.-caprolactone, propionic acid and organic solvent, PA1 (b) distilling the reaction mixture from (a) in a first distillation unit to obtain a distillate comprising the organic solvent and a distillation residue, PA1 (c) introducing the distillation residue from (b) at a point into a second distillation unit to obtain a distillate comprising propionic acid and unreacted cyclohexanone, removing from the second distillation unit, separately from one another and at a point below the point of introduction into the second distillation unit, .epsilon.-caprolactone and any high-boiling constituents, and, PA1 (d) distilling in a third distillation unit the distillate from (c) to obtain a distillate consisting essentially of propionic acid and a distillation residue comprising a mixture of propionic acid and cyclohexanone.