Pramipexole hydrochloride hemihydrate and preparation method thereof

The invention discloses a pramipexole hydrochloride hemihydrate. The pramipexole hydrochloride hemihydrate has a molecular formula of C10H17N3S.2HCl.0.5H2O and a structural formula shown in a formula(I). The hemihydrate is in a crystalline form, and an X-ray powder diffraction diagram of the crystal form has characteristic peaks at positions with reflection angles 2[theta] of 6.40 degrees, 11.80degrees, 12.58 degrees, 13.42 degrees, 15.32 degrees, 16.98 degrees, 17.68 degrees, 19.24 degrees, 21.10 degrees, 23.96 degrees, 24.54 degrees, 25.50 degrees, 26.34 degrees and 28.22 degrees. In addition, the invention also discloses a preparation method of the hemihydrate. The pramipexole hydrochloride hemihydrate provided by the invention has good stability, and a preparation prepared by the pramipexole hydrochloride hemihydrate has high dissolution rate and bioavailability and has a high medicinal value. Meanwhile, the preparation method has the advantages of low cost, small environmental pollution, simple and conve