Reaktion #59370

Reaktionsgleichung

Rochelle's salt

Water

2-[(2-bromophenyl)-hydrazono]-N-butyl-2-cyanoacetamide

aluminum chloride

→

title compound

Ausbeute 26.1%

4-Amino-8-bromo-N-butyl-cinnoline-3-carboxamide

Ausbeute 26.1%

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthen cooled to ˜0° C
2. 2
   workup.STIRRINGThe reaction was stirred for 25 minutes
3. 3
   workup.ADDITIONpoured into a separator funnel
4. 4
   Sonstigewas quickly removed
5. 5
   WaschenThe organic layer was washed with Rochelle's salt and brine
6. 6
   Trocknendried over magnesium sulfate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated
9. 9
   Sonstigeto give 2.6 g slightly crude product which
10. 10
    Sonstigewas purified on silica gel using a gradient of 20 to 60% ethyl acetate in hexane
11. 11
    SonstigeRecrystallization from ethyl acetate/hexanes (10 mL each, 0° C. overnight)

Vorschrift

To a solution of 2-[(2-bromophenyl)-hydrazono]-N-butyl-2-cyanoacetamide (2.5 g, 7.7 mmol) in anhydrous toluene (Aldrich, 50 mL) under N2 was added portion-wise aluminum chloride (Aldrich, 3.1 g, 23.2 mmol) over 5 minutes. The mixture was heated to 90° C. with vigorous stirring for 1.5 hours then cooled to ˜0° C. Water (3 mL) was added drop wise followed by careful addition of Rochelle's salt (saturated aqueous potassium sodium tart rate, 50 mL). The reaction was stirred for 25 minutes and then poured into a separator funnel. The aqueous layer contained a thick white precipitate and was quickly removed. The organic layer was washed with Rochelle's salt and brine, dried over magnesium sulfate, filtered and concentrated to give 2.6 g slightly crude product which was purified on silica gel using a gradient of 20 to 60% ethyl acetate in hexane. Recrystallization from ethyl acetate/hexanes (10 mL each, 0° C. overnight) afforded the title compound as a white solid (650 mg, 26%). 1H NMR (300.132 MHz, CDCl3) δ 8.55 (bs, 1H), 8.13 (dd, J=7.4, 1.0 Hz, 1H), 7.82 (dd, J=8.5, 1.0 Hz, 1H), 7.50 (dd, J=8.5, 7.6 Hz, 1H), 3.52 (q, J=6.6 Hz, 2H), 1.65 (quintet, J=7.2 Hz, 2H), 1.47 (sextet, J=7.3 Hz, 2H), 0.97 (t, J=7.3 Hz, 3H). MS APCI, m/z=323/325 (M+H). HPLC 1.93 min.

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