Methyl 4-(2-chloro-5-nitropyrimidin-4-yl)-3-methylmorpholine-3-carboxylate → 2-chloro-6a-methyl-6a,7,9,10-tetrahydro-[1,4]oxazino[3,4-h]pteridin-6(5H)-one

Participants

Reaction Steps

Methyl 4-(2-chloro-5-nitropyrimidin-4-yl)-3-methylmorpholine-3-carboxylate (crude material, 8.4 g, about 20 mmol) and vanadyl acetylacetonate (0.7 g, 2.64 mmol) were mixed in THF (80 ml). The reaction mixture was hydrogenated under one atmosphere of hydrogen at 35° C. for 18 hours. The starting material was consumed. The reaction mixture was cooled to room temperature. MeOH (10 ml) was added to reaction mixture and stirred for 10 minutes. The mixture was filtered through a Celite® pad. The Celite® pad was washed with mixture of THF (60 ml) and MeOH (10 ml) twice and then a mixture of dichloromethane (80 ml) and methanol (20 ml) three times. The filtrate was combined with washes and concentrated to about 30 ml at which point a solid had precipitated out. EtOAc (40 ml) was added and the mixture was stirred for 10 minutes. The solid was collected by filtration, washed with EtOAc (50 ml) to afford 2.54 g of 2-chloro-6a-methyl-6a,7,9,10-tetrahydro-[1,4]oxazino[3,4-h]pteridin-6(5H)-one. 1H NMR (400 MHz, CDCl3) δ=1.44 (s, 3H), 3.23 (m, 1H), 3.53 (m, 1H), 3.69 (d, 1H), 3.88-3.99 (m, 3H), 7.67 (s, 1H), 10.98 (s, 1H)

Provenance & Evidence