An improved process for the preparation of (S,S)-2, 8-diazabicyclo [4,3,0] nonane, a key intermediate of moxifloxacin hydrochlorideAuthor(s): Narender Rao Somisetti, Veeraiah Mynam, Nageswar Rao Challa, Somaiah Sripathi,Raju Veeramalla, Srinivasa Rao Peddi, K.Sudhakar Babu
This contribution highlights the improved process for the preparation of high pure (S, S)-2, 8-diazabicyclo [4,3,0] nonane, a valuable intermediate of Moxifloxacin hydrochloride.Arobust process was described for resolution step using water as solvent and systematically studied the impact of factors such as water quantity, temperature and mole ratio of resolving agent that influence the resolution. The racemisation process of the undesired isomer using acid is provided. Purification conditions were optimized for the amide reduction step by screening the effect of solvent washings at different pH values. The final debenzylation conditions were altered to reduce the time cycle and reaction temperature whichminimize the impurity formation.