Reaktion #1973949

Reaktionsgleichung

Phosphorus trichloride

diethyl 7-(hydroxymethyl)dipyrido[3,2-f:2′,3′-h]quinoxaline-2,3-dicarboxylate

→

glass

Ausbeute 26.0%

Diethyl 7-(chloromethyl)dipyrido[3,2-f:2′,3′-h]quinoxaline-3,2-dicarboxylate

Ausbeute 26.0%

Lösungsmittel

CHCl3

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture was heated
2. 2
   Temperaturunder reflux for 6 h
3. 3
   SonstigeThe reaction was quenched by addition of concentrated Na2CO3 solution (150 ml)
4. 4
   SonstigeThe layers were separated
5. 5
   Extraktionthe water was extracted by CH2Cl2 (3×150 ml) and CHCl3 (1×50 ml)
6. 6
   TrocknenThe organic layer was dried over K2CO3
7. 7
   SonstigeThe solvent was removed under reduced pressure
8. 8
   Sonstigeto give the crude product
9. 9
   SonstigePurification

Vorschrift

Phosphorus trichloride (473 mg, 3.44 mmol) was added to a solution diethyl 7-(hydroxymethyl)dipyrido[3,2-f:2′,3′-h]quinoxaline-2,3-dicarboxylate (350 mg, 0.86 mmol) in CHCl3 (150 ml). The reaction mixture was heated under reflux for 6 h and allowed to cool down to room temperature afterwards. The reaction was quenched by addition of concentrated Na2CO3 solution (150 ml). The layers were separated and the water was extracted by CH2Cl2 (3×150 ml) and CHCl3 (1×50 ml). The organic layer was dried over K2CO3. The solvent was removed under reduced pressure to give the crude product. Purification was achieved by chromatography on alumina (gradient elution: CH2Cl2 to 2% CH3OH—CH2Cl2) The product was obtained as a yellow glass (95 mg, 0.22 mmol, 26%). 1H NMR (300 MHz, CDCl3): δ 1.45 (6H, t, J=7.2, OCH2CH3), 4.53 (4H, q, J=7.2, OCH2), 5.07 (2H, s, CH2Cl), 7.78 (1H, dd, J=8.1, 4.5, H11), 8.05 (1H, d, J=8.4, H6), 9.31 (1H, dd, J=4.5, 1.8, H10), 9.50 (1H, dd, J=8.1, 1.8, H12), 9.53 (1H, d, J=8.7, H5). 13C NMR (75 MHz, CDCl3): δ14.4 (CH3), 47.3 (CH2Cl), 63.2 (OCH2), 123.8 (C11), 124.6 (C6), 125.6 (q Ar), 126.6 (q Ar), 134.5 (C12), 135.7 (C5), 140.1 (q Ar), 140.4 (q Ar), 144.3 (q Ar), 144.4 (q Ar), 147.6 (q Ar), 148.1 (q Ar), 153.8 (C10), 161.0 (C7), 165.0 (CO), 165.1 (CO). m/z (ES+) 447 (MNa+).

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