Diisopropylethylamine → 1,1-Dimethylethyl N-((6-chloro-4-hydroxy-2-oxo-2',3',5',6'-tetrahydro-spiro[naphthalene-1,4'-pyran]-3-yl)carbonyl)-2-methylalaninate

Participants

Reaction Conditions

Reaction Steps

Ethyl 6-chloro-4-hydroxy-2-oxo-2′,3′,5′,6′-tetrahydro-spiro[naphthalene-1,4′-pyran]-3-carboxylate (320 mg, 950 μmol, prepared according to Example 1 A-C) was dissolved in 1,4-dioxane (950 μL) and N-ethyl-N-isopropylpropan-2-amine (507 μL, 2851 μmol) before tert-butyl 2-amino-2-methylpropanoate hydrochloride (279 mg, 1425 μmol) was added. The resulting mixture was heated at 80° C. for 24 hours and then diluted with 150 mL of EtOAc. The resulting mixture was added to a separatory funnel, partitioned with NaHCO3 (saturated, aqueous), washed with saturated aqueous NaHCO3 (2×75 mL), separated, dried over Na2SO4, and concentrated in vacuo to give the title compound (260 mg) after chromatography as an amorphous solid. MS (m/z)=394 (M+H-tert-butyl)+.

Provenance & Evidence