Process for preparing oligomers and telechels having carboxy-piperazine units, and new oligomers and telechels of poly(carboxypiperazine)

US4758652A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Walter Heitz · Kirchhain, DE
• Reinhold Schwalm · Monsheim, DE

Key dates

• Filing date: Nov 17, 1986
• Grant date: Jul 19, 1988
• Expiry date: Nov 17, 2006

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D295/215
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for preparing oligomers and telechels of poly(carboxy-piperazine) and new oligomers the telechels of poly(carboxy-piperazine), wherein the process involves condensation of piperazine or piperazine-N-carboxylic acid esters or their reaction with piperazine or piperidine derivatives to form an intermediate which is reacted with diphenyl carbonate in the presence of a tertiary amine.