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

Participants

Reaction Conditions

Reaction Steps

Ethyl 6-chloro-4-hydroxy-2-oxo-2′,3′,5′,6′-tetrahydro-spiro[naphthalene-1,4′-pyran]-3-carboxylate (610 mg, 1811 μmol, prepared in Example 1 A-C) was dissolved in 1,4-dioxane (1811 μL) and N-ethyl-N-isopropylpropan-2-amine (947 μL, 5434 μmol). L-Alanine t-butyl ester hydrochloride (494 mg, 2717 μmol) was added, and the reaction mixture was heated to 80° C. for 24 hours. The reaction mixture was then cooled to ambient temperature, diluted with 150 mL of EtOAc, added to a separatory funnel, partitioned with NaHCO3 (saturated, aqueous), washed 2 times with 50 mL of NaHCO3 (saturated, aqueous), separated, dried over Na2SO4, and concentrated in vacuo to give the title compound (525 mg) as an oil after flash chromatography. MS (m/z)=436 (M+H)+.

Provenance & Evidence