Methanol → HCID 18918169, compound

HRID 1290771Notes

Reaction equation

HRID 1290771 reaction equation
[CH:1]([NH:3][CH:4]1[C:16]2[N:15]3[CH:17]=[CH:18][N:19]=[C:14]3[C:13](=[O:20])[NH:12][C:11]=2[C:10]2[CH:9]=[CH:8][CH:7]=[CH:6][C:5]1=2)=O.CO>O1CCCC1>[CH3:1][NH:3][CH:4]1[C:16]2[N:15]3[CH:17]=[CH:18][N:19]=[C:14]3[C:13](=[O:20])[NH:12][C:11]=2[C:10]2[CH:9]=[CH:8][CH:7]=[CH:6][C:5]1=2

Participants

4

Reactant 2

HCID 887MethanolHCID 18975475HCID 18975475, compound

Product 1

HCID 18918169HCID 18918169, compoundYield 8.9%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
0 °C

Procedure

To a suspension of 7 g of 10-formamido-5H,10H-imidazo[1,2-a]indeno[1,2-e]pyrazin-4-one in 225 ml of anhydrous tetrahydrofuran maintained at 0° C. are added, dropwise over 10 minutes, 62.5 ml of a 2M solution of borane/methyl sulphide complex in tetrahydrofuran. The mixture is stirred for 10 minutes at the same temperature and then for 18 hours at a temperature in the region of 20° C. After addition of 100 ml of methanol and stirring for 1 hour, the insoluble material is separated out by filtration and washed with 25 ml of methanol. The filtrate and the washings are combined and concentrated to dryness under reduced pressure (15 mmHg; 2 kPa) at 35° C. The product obtained (3.9 g) is chromatographed on 390 g of neutral silica gel (0.020-0.045 mm) contained in a column of diameter 5.3 cm, eluting with a chloroform/methanol/28% aqueous ammonia mixture (82/15/3 by volume) and collecting 35 ml fractions. Fractions 25 to 31 are combined and concentrated to dryness under reduced pressure (1 mmHg; 0.13 kPa) at 90° C. 0.59 g of 10-methylamino-5H,10H-imidazo[1,2-a]indeno[1,2-e]-pyrazin-4-one is thus obtained, melting at 184° C. [N.M.R. spectrum: [200 MHz; (CD3) 2SO d6 ; δ in ppm): 1.85 (s, 3H: --CH3); 5.13 (8, 1H: --CH-- 10); 7.36 and 7.43 (2t broad, J=8 Hz, 1H each: --H7 and --H8); 7.61 and 8.17 (2s broad, 1H each: --H of the imidazole); 7.62 and 7.85 (2d broad, J=8 Hz, 1H each: --H6 and --H9); 12.35 (broad s, 1H: --CONH-- of the ring)].

Workup

  1. additionare added, dropwise over 10 minutes
  2. waitfor 18 hours at a temperature in the region of 20° C
  3. stirringstirring for 1 hour
  4. customthe insoluble material is separated out by filtration
  5. washwashed with 25 ml of methanol
  6. concentrationconcentrated to dryness under reduced pressure (15 mmHg; 2 kPa) at 35° C
  7. customThe product obtained (3.9 g)
  8. customis chromatographed on 390 g of neutral silica gel (0.020-0.045 mm)
  9. washeluting with a chloroform/methanol/28% aqueous ammonia mixture (82/15/3 by volume)
  10. customcollecting 35 ml fractions
  11. concentrationconcentrated to dryness under reduced pressure (1 mmHg; 0.13 kPa) at 90° C

Sources & evidence

ORD record
ord-96fb88c59b4748e4a4527061482ee82c
Source dataset
uspto-grants-1998_05
Patent number
US05753657

Reaction notes

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