- May 09, 2018 -
2,7-Dibromo-9H-fluoreneis an important intermediate material for the synthesis of fine chemicals, which is widely used in the synthesis and preparation of dyes, photoconductive materials and luminescent materials. It is reported at home and abroad that the direct bromination of fluorene and bromine in the presence of iron powder or Lewis acid, has low utilization rate of bromine atoms, high toxicity and many side reactions. It is difficult to separate and purify the product.
Dalian University of Technology has developed a method for the preparation of 2,7-Dibromo-9H-fluorene with mild reaction conditions, high efficiency, low cost, simple operation and no pollution to the environment.
In the organic solvent solution of fluorene, adding bromate solution of acid or hydrobromic acid, adding oxidant aqueous solution. HPLC monitoring reaction was completed, then saturated sulfurous acid solution was added to remove unreacted bromine and filtrated to obtain 2,7-Dibromo-9H-fluorene.
The reaction of active bromine and fluorene produced by dropping oxidant in the medium made of hydrobromic acid or bromate and acid can be carried out at room temperature. It also avoids the safety and corrosion problems in the process of the by-product hydrogen bromide gas coming out and the transport and use of bromine, improves the utilization ratio of bromine atoms, reduces the equipment requirements, simplifies the production process and reduces the production cost. The high purity of 2,7-Dibromo-9H-fluorenecan be prepared.