Preparation and characterization of a novel polymorph of indiplon, Form α

A new polymorph α of indiplon was discovered, initially prepared by two methods, and further characterized by various means, including single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), variable temperature powder X-ray diffraction (VT-PXRD), differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), Fourier transform Raman (FT-Raman) spectroscopy and solubility determination. The crystal structure of Form α described by SCXRD, differ from the previously other three polymorphs.