Process for preparing 2,7-dibromine fluorenes

This invention relates to a preparation method for 2,7-dibromofluorene from 2,7-dibromo-fluorenone. Said method includes (1) adding zinc and mercuric chloride in the reactor, adding hydrochloric acid and oscillating at room temperature for 5-10 min, decanting solution to obtain zinc amalgam, and (2) adding 2,7-dibromo-fluorenone and ethanol in zinc amalgam, heating, adding hydrochloric acid after beginning to return, and carrying out reaction to obtain the final product. The invention has the advantages of simple operation, simple separation and purification fro product, high yield, low cost, and small environmental pollution of ethanol.