Diisopropylethylamine → 2-[1-(2-Cyclopropyl-6-chloro-5-methyl-pyrimidin-4-yl)-piperidin-4-yl]-[1,8]naphthyridine

Participants

Reaction Conditions

Reaction Steps

20 ml of dimethylacetamide and 3.36 ml (19.2 mmoles) of diisopropylethylamine are added into a single-necked flask containing 1.5 g (7.39 mmoles) of 2-cyclopropyl-4,6-dichloro-5-methyl-pyrimidine and 1.58 g (7.39 mmoles) of 2-piperidin-4-yl-[1,8]naphthyridine. This mixture is heated at 100° C. overnight. The next day 0.2 equivalent of naphthyridine is added and the reaction mixture is heated for another 6 hours, followed by returning to ambient temperature before concentration to dryness. The residue obtained is taken up in a mixture of water, ethyl acetate and a saturated solution of sodium bicarbonate. The organic phase is separated and the aqueous phase reextracted with ethyl acetate. The collected organic phases are dried over magnesium sulphate then the solvent is evaporated off under reduced pressure (2 kPa). The residue is chromatographed on silica gel eluting with a gradient of heptane-ethyl acetate (50-50) to 100% ethyl acetate. 1.45 g of expected product is obtained.

Provenance & Evidence