1-amino-2,2-difluorocyclopropane

PURPOSE: To provide a new cyclopropylamine useful as a intermediate for preparing compounds having potent antibacterial activity. CONSTITUTION: The compound of formula I and its salts, for example, 1- amino-2,2-difluorocyclopropane hydrochloride which can be obtained by the method in accordance with the reaction process from 2,2-difluorocyclopropane as a starting substance. 1-Amino-2,2-difluorocyclopropane hydrochloride is allowed to react with ethyl 3-ethoxy-2-(2,3,4,5-tetrafuorobenzoyl)-acrylate and the obtained reaction product is boiled with NaF in DMF for 2 hours thereby obtaining a compound of formula II. This compound is subsequently allowed to react with piperazine so as to produce 6,8-difluoro-1-(2,2- difluorocyclopropyl)-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylic acid of formula III having anti-bacterial activity. In the formula I, X is F, Cl. COPYRIGHT: (C)1993,JPO