Potassium Carbonate → (S)-3-[(S)-7-((E)-2-ethoxy-vinyl)-4-methyl-3-oxo-2,3,4,10-tetrahydro-9-oxa-1,2,4a-triaza-phenanthren-6-ylamino]-3-methyl-pyrrolidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of (S)-3-((S)-7-bromo-4-methyl-3-oxo-2,3,4,10-tetrahydro-9-oxa-1,2,4a-triaza-phenanthren-6-ylamino)-3-methyl-pyrrolidine-1-carboxylic acid tert-butyl ester (isomer A, SFC (Table 1, Method 52) Rt=2.880 min, 0.030 g, 0.061 mmol), K2CO3 (0.017 g, 0.121 mmol), (E)-2-(2-ethoxyvinyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (0.018 g, 0.091 mmol) and PdCl2(dppf)-CH2Cl2 adduct (4.96 mg, 6.07 μmol) in dioxane (2 mL) and water (0.3 mL) was stirred at 90° C. for 14 h. The reaction mixture was cooled to ambient temperature and concentrated in vacuo. The residue was purified by column chromatography on silica gel (eluting with 3%˜20% EtOAc in petroleum ether) to give (S)-3-[(S)-7-((E)-2-ethoxy-vinyl)-4-methyl-3-oxo-2,3,4,10-tetrahydro-9-oxa-1,2,4a-triaza-phenanthren-6-ylamino]-3-methyl-pyrrolidine-1-carboxylic acid tert-butyl ester (10 mg, 34%) as a pale solid. LC/MS (Table 1, Method 25) Rt=0.826 min; MS m/z: 508 [M+Na]+.

Provenance & Evidence