Potassium Phosphate, Tribasic → methyl[6-({1-[4-(2-tert-butoxy-2-oxoethoxy)phenyl]-2-methylindolizin-3-yl}carbonyl)-2,4-dioxo-1,4-dihydroquinazolin-3(2H)-yl]acetate

Participants

Reaction Steps

Methyl {6-[(1-bromo-2-methylindolizin-3-yl)carbonyl]-2,4-dioxo-1,4-dihydroquinazolin-3(2H)-yl}acetate [described in Step 1.5.] (0.85 g; 1.81 mmol), tert-butyl[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2yl)phenoxy]acetate [CAS 769968-17-4; D. Fan et al, Journal of Organic Chemistry, 2007, 72(14), 5350-5357] (0.91 g; 2.71 mmol), 5.4 mL of a molar solution of potassium phosphate, 17 mL of 1,2-dimethoxyethane and the catalyst PdCl2(dppf) (198 mg; 0.27 mmol) are successively introduced into a reactor, under argon. The mixture is heated at reflux for 2 hours under argon. The reaction medium is filtered through Celite. The filtrate is diluted with ethyl acetate and the solution is washed with a saturated solution of potassium hydrogen carbonate and with a saturated solution of sodium chloride, and then dried over sodium sulphate and concentrated to dryness. The residue obtained is purified by flash chromatography on silica (DCM/EtOH: 100/0 to 80/10). 0.46 g (42%) of a yellow-red powder is obtained.

Provenance & Evidence