Diisopropylethylamine → methyl 2-chloro-4-((1R,3S)-3-hydroxycyclohexylamino)pyrimidine-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirring solution of methyl 2,4-dichloropyrimidine-5-carboxylate (4.00 g, 19.32 mmol) in THF (85 mL) was added DIEA (3.37 mL, 19.32 mmol). The resulting mixture was cooled to −78° C. in a dry ice/acetone bath. A solution of (1S,3R)-3-aminocyclohexanol (2.448 g, 21.25 mmol; prepared as described in Tetrahedron: Asymmetry 15:2051-2056 (2004)) in 40 mL THF was added at such a rate that the temperature remained at −78° C. The resulting mixture was stirred at −78° C. for 1 h. The reaction mixture was then concentrated to dryness and diluted with 200 mL ethyl acetate and 75 mL of a 1:1 mixture of water and an aqueous saturated sodium bicarbonate solution. The layers were separated and the aqueous layer back-extracted with 100 mL ethyl acetate. The combined ethyl acetate layers were washed with 50 mL of a saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated to an oil that solidified upon standing. The solid was triturated with diethyl ether (5 mL), filtered, rinsed with diethyl ether (5 mL) and dried in vacuo to afford methyl 2-chloro-4-((1R,3S)-3-hydroxycyclohexylamino)pyrimidine-5-carboxylate (3.7 g, 12.95 mmol, 67% yield) that was used without further purification. MS (ESI) m/z 286.0 [M+1]+.

Provenance & Evidence