PRODUCTION OF FLUOROCARBOXYLIC ACID ANHYDRIDE

摘要

PROBLEM TO BE SOLVED: To synthesize a fluorocarboxylic acid anhydride in high yield with a single step without generating HF having corroding action on its reactor by using RfCOF and an alkali metal or alkaline earth metal carbonate. SOLUTION: The objective fluorocarboxylic acid anhydride of the formula (BfCO)2O can be produced by reacting a compound of the formula RfCOF (Rf is a 1-30C saturated hydrocarbon group substituted at least a part of H atoms with F or F and other halogens and optionally containing oxygen) with a compound of the formula MmCO3 [M is an alkali metal or an alkaline earth metal; (m) is 2 when M is an alkali metal and 1 when M is an alkaline earth metal] preferably at 20-100 deg.C, preferably under a reaction pressure between atmospheric pressure and 20 kg/cm2 (gauge). For example, the compound of the formula (C7F15CO)2O can be produced by stirring C7F15 and LiCO3 and reacting at 90 deg.C for 6 hr. The obtained compound of the formula (RfCO)2O can be used as an agent for introducing RfCO group or a dehydration agent.