Diisopropylethylamine → (5R)-5-ethyl-5-methyl-3-[6-(7-methylspiro[2H-benzofuran-3,1'-cyclopropane]-4-yl)oxy-3-pyridyl]imidazolidine-2,4-dione

Participants

Reaction Steps

To a solution of triphosgene (30 mg, 0.1 mmol) in dry DCM (1 ml) at 0° C., under nitrogen atmosphere, DIPEA (0.175 ml, 1.0 mmol) was added followed by the addition (slowly added) of a solution of 6-(7-methylspiro[2H-benzofuran-3,1′-cyclopropane]-4-yl)oxypyridin-3-amine (Intermediate 15, 27 mg, 0.1 mmol) in dry DCM (2 ml) and the reaction mixture was stirred for 15 minutes at the same temperature. After that a solution of Methyl (R)-2-amino-2-methyl-butyrate hydrochloride (33 mg, 0.2 mmol) in dry DCM (2 ml) was added and the reaction mixture was stirred for 30 minutes at 0° C. The reaction was quenched with a 1M aqueous solution of HCl (5 ml), diluted with DCM (10 ml) and two phases were separated. The organic layer was washed with brine (10 ml), dried (Na2SO4), filtered and evaporated affording the urea intermediate as yellow foam.

Provenance & Evidence