Production of bis-1,3,4-oxadiazolin-5-on-2-yl-alkane compounds, used e.g. for polymer production, involves reacting alkanedioic acid dihydrazide compounds with phosgene in aqueous solution at constant, controlled pH

摘要

A method for the production of bis-(1,3,4-oxadiazolin-5-on- 2-yl)-alkanes, by reacting corresponding alkanedicarboxylic acid dihydrazides with phosgene in aqueous solution, involves constantly adjusting the reaction solution to pH 6.0-7.5 during the reaction. The production of bis-(1,3,4-oxadiazolin-5-on-2-yl)-alkanes of formula (I) involves reacting alkanedicarboxylic acid dihydrazides of formula H2N-NH-CO-R-CO-NH-NH2 (II) in aqueous solution with phosgene gas while the solution is constantly adjusted to pH 6.0-7.5 during the reaction. R = 1-6C aliphatic or cycloaliphatic hydrocarbylene.