Reaktion #957892

Reaktionsgleichung

acetic acid

N1-(3-bromoimidazo[1,2-b]pyridazin-6-yl)ethane-1,2-diamine

acetone

sodium cyanoborohydride

N2

→

N1-(3-bromoimidazo[1,2-b]pyridazin-6-yl)-N2-isopropylethane-1,2-diamine

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeclosed with a septum
2. 2
   Filtrationfiltered
3. 3
   SonstigeThe filtrate was evaporated
4. 4
   Sonstigethe residue partitioned between 10% (w/v) aqueous NaHCO3 and ethyl acetate
5. 5
   TrocknenThe extract was dried (CaSO4)
6. 6
   Sonstigeevaporated
7. 7
   Sonstigeto afford a clear orange oil
8. 8
   SonstigeThis oil was triturated in heptane
9. 9
   Sonstigeto precipitate N1-(3-bromoimidazo[1,2-b]pyridazin-6-yl)-N2-isopropylethane-1,2-diamine as 2.3 g of yellow powder, mp. 87-88° C

Vorschrift

Glacial acetic acid [64-19-7] (1.6 mL, 28.0 mmol) was added to a stirred suspension of N1-(3-bromoimidazo[1,2-b]pyridazin-6-yl)ethane-1,2-diamine (7.0 g, 27.2 mmol), acetone [67-64-1] (2.4 mL, 32.6 mmol), sodium cyanoborohydride [25895-80-7] (1.8 g, 27.2 mmol) and powdered, activated 4 Angstrom molecular sieve (4 g). The flask was N2 blanketed, closed with a septum, and the mixture allowed to stir at ambient temperature for 3d, then filtered. The filtrate was evaporated, and the residue partitioned between 10% (w/v) aqueous NaHCO3 and ethyl acetate. The extract was dried (CaSO4), and evaporated to afford a clear orange oil. This oil was triturated in heptane to precipitate N1-(3-bromoimidazo[1,2-b]pyridazin-6-yl)-N2-isopropylethane-1,2-diamine as 2.3 g of yellow powder, mp. 87-88° C. 1H NMR (400 MHz, DMSO-d6) δ ppm 0.99 (d, J=6.32 Hz, 5H) 1.60 (br. s., 1H) 2.71-2.81 (m, 3H) 3.34 (q, J=6.32 Hz, 2H) 6.73 (d, J=9.85 Hz, 1H) 7.07 (t, J=5.31 Hz, 1H) 7.47 (s, 1H) 7.68 (d, J=9.60 Hz, 1H). 13C NMR (100 MHz, DMSO-d6) δ ppm 22.92, 41.48, 45.29, 47.81, 98.98, 112.99, 125.26, 130.24, 136.53, 154.24. LRMS (ESI) m/z 297.9/299.9 [(M+H)]+, calc'd for C11H16BrN5. 289.19.

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