Reaktion #56657

Reaktionsgleichung

ethyl 9-(acetoxymethyl)-9-(chloromethyl)-3-hydroxy-4-oxo-4,6,7,9-tetrahydropyrimido[2,1-c][1,4]oxazine-2-carboxylate

benzyl bromide

K2CO3

→

title compound

Ethyl 9-(acetoxymethyl)-3-(benzyloxy)-9-(chloromethyl)-4-oxo-4,6,7,9-tetrahydropyrimido[2,1-c][1,4]oxazine-2-carboxylate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeSolvent was removed in-vacuo
2. 2
   workup.DISSOLUTIONthe crude material was dissolved in ethyl acetate (30 mL)
3. 3
   Waschenwashed with water (30 mL) and brine (30 mL)
4. 4
   TrocknenThe organic solution was dried (Na2SO4)
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated
7. 7
   Sonstigeto give an amber oil
8. 8
   SonstigeThis was purified by flash column chromatography
9. 9
   Wascheneluting with 5% Et2O in CH2Cl2
10. 10
    Einengenconcentrated in-vacuo

Vorschrift

A solution of ethyl 9-(acetoxymethyl)-9-(chloromethyl)-3-hydroxy-4-oxo-4,6,7,9-tetrahydropyrimido[2,1-c][1,4]oxazine-2-carboxylate (2.05 g, 5.68 mmol) in dimethylfomamide (60 mL) was treated with benzyl bromide (1.46 g, 8.5 mmol, Aldrich) and K2CO3 (1.26 g, 9.1 mmol) and stirred for 16 hrs. Solvent was removed in-vacuo and the crude material was dissolved in ethyl acetate (30 mL) and washed with water (30 mL) and brine (30 mL). The organic solution was dried (Na2SO4), filtered, and concentrated to give an amber oil. This was purified by flash column chromatography, eluting with 5% Et2O in CH2Cl2. Product fractions were pooled and concentrated in-vacuo to give the title compound as a colorless oil: 1H NMR (500 MHz, CDCl3) δ ppm 7.45 (2H, d, J=7.32 Hz), 7.29-7.39 (3H, m), 4.68 (1H, d, J=1 1.90 Hz), 4.37 (1H, d, J=1 1.90 Hz), 4.31 (2H, q, J=7.22 Hz), 4.16-4.24 (2H, m), 4.09-4.16 (1H, m), 4.06 (1H, d, J=11.29 Hz), 3.95-4.03 (1H, m), 3.89 (1H, d, J=1 1.29 Hz), 2.06 (3H, s), 1.56 (2H, s), 1.29 (3H, t, J=7.17 Hz); 13C NMR (126 MHz, CDCl3) δ ppm 170.16, 164.04, 158.67, 150.65, 141.94, 141.67, 136.51, 128.59 128.52, 128.45, 79.57, 74.51, 65.90, 62.11, 60.59, 49.08, 42.16, 20.83, 14.16; HRMS (ESI) calcd for C21H24N2O7Cl (M+H) 451.1272; found 451.1274.

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