Triphenylphosphine → 9-benzyloxy-6-(2-bromobenzyl)-2-isopropyl-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione

Participants

Reaction Steps

To a stirred solution of 5-benzyloxy-2-(2-bromobenzyl)-6-hydroxypyrimidine-4-carboxylic acid (2-hydroxyethyl)-isopropylamide (151) (400 mg, 0.8 mmol) in dichloromethane (10 mL) was added triphenyl phosphine (310.55 mg, 1.18 mmol) at room temperature. The mixture was stirred for 10 min. Then DEAD (0.186 mL, 1.18 mmol) was added at room temperature and the mixture was stirred for another 2 h. After completion of the reaction, the mixture was concentrated under reduced pressure to get a crude product, which was purified using a normal silica column using 2% methanol in dichloromethane to afford 9-benzyloxy-6-(2-bromobenzyl)-2-isopropyl-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione (169) (112 mg, 29%) as a white solid.

Provenance & Evidence