Water → 6-Chloro-2-pyrazin-2-yl-N-[(1S)-2,2,2-trifluoro-1-methylethyl]-5-(2,4,6-trifluorophenyl)pyrimidin-4-amine

Participants

Reaction Conditions

Reaction Steps

In scheme 1, step d, a solution of 4,6-dichloro-2-pyrazin-2-yl-5-(2,4,6-trifluoro-phenyl)-pyrimidine 5 in an aprotic solvent, preferably 1-methyl-2-pyrrolidinone (NMP) in a ratio of 1-10 mL NMP/g of 4,6-dichloro-2-pyrazin-2-yl-5-(2,4,6-trifluoro-phenyl)-pyrimidine 5, preferably 1-5 mL NMP/g of 4,6-dichloro-2-pyrazin-2-yl-5-(2,4,6-trifluoro-phenyl)-pyrimidine 5, most preferably 1 mL NMP/g of 4,6-dichloro-2-pyrazin-2-yl-5-(2,4,6-trifluoro-phenyl)-pyrimidine 5 is added (S)-2,2,2-trifluoro-1-methyl-ethylamine 6 in a mole ratio of 4,6-dichloro-2-pyrazin-2-yl-5-(2,4,6-trifluoro-phenyl)-pyrimidine 5 to (S)-2,2,2-trifluoro-1-methyl-ethylamine 6 is 1:2-1:3 (mole/mole) preferably 1:2.5 (mole/mole) with stirring for over 24-48 h, preferably about 24 hours in a temperature range of about 90-125° C., more preferably at about 110° C. for about 24 hours. In an optional embodiment of the invention, the reaction is sealed to prevent loss of (S)-2,2,2-trifluoro-1-methyl-ethylamine 6. The reaction mixture is diluted with isopropyl alcohol (IPA), IPA to NMP (V/V) of about 1:1-1:5 preferable at about 1:3, then water is added with stirring at about 10-20° C. in a ratio of NMP to water (v/v) of about 1:1-1:5 (v/v), preferably at about 1:3 (v/v) with about 30 minutes of additional stirring and collecting, without the need of chromatography, the solid product, washing with water and drying to give 6-chloro-2-pyrazin-2-yl-N-[(1S)-2,2,2-trifluoro-1-methylethyl]-5-(2,4,6-trifluorophenyl)pyrimidin-4-amine 7. In a preferred embodiment of the invention, 4,6-dichloro-2-pyrazin-2-yl-5-(2,4,6-trifluoro-phenyl)-pyrimidine in 1-methyl-2-pyrrolidinone (NMP) is treated with (S)-2,2,2-trifluoro-1-methyl-ethylamine at about 110° C. for about 24 h and the reaction mixture diluted with IPA, then water 1:3 (v/v) is added slowly forming a precipitated product. The precipitated product is filtered, washed with water, and dried to give a solid product in 92% yield, having a 96% HPLC purity and an enantiomeric excess of >99%. The product 6-chloro-2-pyrazin-2-yl-N-[(1S)-2,2,2-trifluoro-1-methylethyl]-5-(2,4,6-trifluorophenyl)pyrimidin-4-amine 7 is collected without the need for chromatography.

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