Potassium Carbonate → 3-(7-Isopropenyl-4-methyl-3-oxo-2,3,4,10-tetrahydro-9-oxa-1,2,4a-triaza-phenanthren-6-ylamino)-azetidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-(7-bromo-4-methyl-3-oxo-2,3,4,10-tetrahydro-9-oxa-1,2,4a-triaza-phenanthren-6-ylamino)-azetidine-1-carboxylic acid tert-butyl ester (Example 1, Step B, 1.5 g, 3.22 mmol), 4,4,5,5-tetramethyl-2-(prop-1-en-2-yl)-1,3,2-dioxaborolane (1.62 g, 9.66 mmol), K2CO3 (1.33 g, 9.66 mmol) and [1,1′-Bis(diphenylphosphino)ferrocene]palladium(II) chloride (0.544 g, 0.64 mmol) in a mixture of 10% water in dioxane (35 mL) was heated at 80° C. for 2 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 20% EtOAc in petroleum ether) to give 3-(7-isopropenyl-4-methyl-3-oxo-2,3,4,10-tetrahydro-9-oxa-1,2,4a-triaza-phenanthren-6-ylamino)-azetidine-1-carboxylic acid tert-butyl ester (1.15 g, 84%) as a pale solid. LC/MS (Table 1, Method 2) Rt=1.202 min.; MS m/z: 428 [M+H]+.

Provenance & Evidence