Process for the preparation of cyclopropanamine

US5728873A · kind A · utility

Assignee

• Huels Aktiengesellschaft · DE

Inventors

• Wolfgang Kleemiss · Haltern, DE
• Thomas Kalz · Herne, DE

Key dates

• Filing date: Jun 14, 1996
• Grant date: Mar 17, 1998
• Expiry date: Jun 14, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C2601/02
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of cyclopropanamine by Hofmann degradation of cyclopropanecarboxamide, comprising the following steps: PA1 (1) suspending cyclopropanecarboxamide, either (A) in 1.1 to 4 mol of sodium hydroxide, in solution whose concentration is 10 to 50%, per mol of amide, or (B) in a sparing amount of water, PA1 (2) adding 1 to 1.5 mol of hypochlorite, per mol of amide, from a 5 to 15% strength hypochlorite solution at a temperature of 0.degree. to 20.degree. C., PA1 (3) adding 1.1 to 4 mol of sodium hydroxide, in solution whose concentration is 10 to 50%, per mol of amide, in the case where a suspension has been formed according to step (1)(B), PA1 (4) reacting the amide, hypochlorite, and sodium hydroxide for 10 to 60 minutes to form a homogeneous reaction mixture, PA1 (5) continuously passing the homogeneous reaction mixture through a tubular reactor at a temperature of 45.degree. to 260.degree. C., PA1 (6) feeding the reaction output from the tubular reactor into a distillation column and keeping it under reflux with water, wherein cyclopropanamine is distilled off.