Triphenylphosphine → 9-benzyloxy-2-cyclopropyl-6-(1-naphthalen-1-yl-cyclopentylmethyl)-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione

Participants

Reaction Steps

To a solution of 5-benzyloxy-6-hydroxy-2-(1-naphthalen-1-yl-cyclopentylmethyl)-pyrimidine-4-carboxylic acid cyclopropyl-(2-hydroxyethyl)-amide (355) (120 mg, 0.22 mmol) and diisopropyl azodicarboxylate (0.22 mL, 1.12 mmol) in dichloromethane (30 mL) was added triphenyl phosphine (351 mg, 1.34 mmol) at room temperature and the reaction mixture was stirred for 15 min at the same temperature. The yellow color disappeared (silica TLC 5% methanol in ethyl acetate, Rf=0.2). The dichloromethane was removed in vacuo and the crude mass was purified by silica gel (normal, 100-200 mesh) column chromatography using a gradient eluent mixture of 1% to 5% methanol in dichloromethane to get pure 9-benzyloxy-2-cyclopropyl-6-(1-naphthalen-1-yl-cyclopentylmethyl)-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione (356) (106 mg, 92%) as a white solid.

Provenance & Evidence