Benzoyl Peroxide → 1-Benzyl-2-(1-t-butoxycarbonylamino-2-methyl-propyl)-4-methyl-6-oxo-1,6-dihydro-pyrimidine-5-carboxylic Acid Methyl Ester

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Reaction Steps

To a stirred solution of 1-Benzyl-2-(1-t-butoxycarbonylamino-2-methyl-propyl)-4-methyl-6-oxo-1,4,5,6-tetrahydro-pyrimidine-5-carboxylic acid methyl ester (6.37 g, 14.8 mMol) in CCl4 (150 mL) was added K2CO3 (4.0 g, 29 mMol), N-Bromosuccinimde (2.63 g, 14.8 mMol) and Benzoyl peroxide (0.18 g, 0.74 mMol). The reaction was refluxed for 0.5 h, cooled to RT, filtered through a pad of Celite®, and rinsed with CH2Cl2. The filtrate was concentrated under vacuum and purified by flash chromatography (step gradient of 0 to 5% EtOAc in CH2Cl2). The semi-purified product obtained was taken up in a solution of 20% EtOAc in hexane (10 mL) at which point the product began to crystallize out. The mixture was diluted with a solution of 10% Et2O in pet. Et2O (50 mL), triturated, filtered and dried under vacuum to give the title compound (2.56 g, 40%) as a white solid: MS (ES) m/e 432.2 and 430.2 (M+H)+.

Provenance & Evidence