Methylamine → Rosuvastatin MethanaMine Salt

Participants

Reaction Conditions

Reaction Steps

A solution of methylamine in methanol (1.4 ml of a 40% solution) was added with stirring to a solution of (E)-7-[4-(4-fluorophenyl)-6-isopropyl-2-[methyl(methylsulfonyl)amino]pyrimidin-5-yl]-(3R,5S)-3,5-dihydroxyhept-6-enoic acid (obtained as described below) at −5° C. The mixture was stirred at 30° C. for 90 minutes and then cooled to 3° C. The crystalline product was collected by filtration, washed with acetonitrile and dried under vacuum at 40° C. to give methylammonium (E)-7-[4-(4-fluorophenyl)-6-isopropyl-2-[methyl(methylsulfonyl)amino]pyrimidin-5-yl]-(3R,5S)-3,5-dihydroxyhept-6-enoate (3.85 g; 87.9% yield) as white crystals. (The same crystalline salt was obtained when a 40% solution of methylamine in water (1.1 ml) was used). The X-ray powder diffraction spectra (XRD) for a typical sample of the crystalline methylammonium salt is shown in FIG. 2 hereinafter. The ten most prominent peaks in the XRD occur at about 2-theta=8.2, 12.3, 15.7, 16.5, 17.6, 18.7, 19.9, 21.0, 24.3 and 25.9°.

Provenance & Evidence