Patent ID: 8324383

Claim:
A method for preparing Compound I having the formula wherein Compound I is greater than 90% by weight polymorph Form A characterized by an X-ray powder diffraction pattern with salient features being major diffraction lines as follows: Position (°2θ) 9.44 10.84 17.82 18.75 25.87 28.52 using Cu-Kα radiation; the method comprising: (a) crystallization from any of the following solvent systems consisting of (i) acetone, (ii) acetonitrile; (iii) butanol, (iv) dimethylsulfoxide; (v) dioxane; (vi) ethanol; (vii) ethanol and isopropyl alcohol; (viii) ethanol and water; (ix) ethyl acetate; (x) heptane; (xi) isopropanol; (xii) isopropyl acetate; (xiii) methyl ethyl ketone; (xiv) methyl isobutyl ketone; (xv) 2,2,2-trifluoroethanol; (xvi) tetrahydrofuran; (xvii) toluene; (xviii) water; and (xix) ethanol and heptane; or (b) by the conversion of an amorphous Form 1 of Compound I by heating the amorphous Form 1 of Compound I at a temperature of >40° C., by subjecting the amorphous Form 1 of Compound I to relative humidity of between about 85% and 95% or organic vapors selected from the group consisting of ethyl acetate, isopropyl alcohol and tetrafluoroethylene, or by wet milling of amorphous Form 1 of Compound I with water.