Potassium Phosphate, Tribasic → Benzyl 4-(3-{[3-(2-tert-butoxy-2-oxoethyl)-2,4-dioxo-1,2,3,4-tetrahydroquinazolin-7-yl]carbonyl}-2-methylindolizin-1-yl)benzoate

Participants

Reaction Conditions

Reaction Steps

{4-[(Benzyloxy)carbonyl]phenyl}boronic acid (0.7 g, 2.73 mmol), 5.5 mL of a molar solution of potassium phosphate and the catalyst PdCl2(dppf) (192 mg, 0.27 mmol) are added to a solution of tert-butyl {7-[(1-bromo-2-methylindolizin-3-yl)carbonyl]-2,4-dioxo-1,4-dihydroquinazolin-3(2H)-yl}acetate [described in Step 3.2.] (1 g, 1.82 mmol) in 20 mL of DMF placed in a microwave reactor under nitrogen. The reactor is sealed and the solution is heated for 30 min at 80° C. in a microwave. The reaction medium is cooled and run into a molar solution of KHSO4, and extracted with EtOAc. The organic phase is washed with a saturated aqueous solution of NaCl, dried over Na2SO4, and concentrated to dryness. The residue obtained is purified by flash chromatography on silica (DCM/EtOH: 100/0 to 80/20] to give 1.08 mg (92%) of a yellow solid.

Provenance & Evidence